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19,600 | Renal Denervation for Ventricular Arrhythmia in Patients with Implantable Cardioverter Defibrillators. | To investigate the efficacy of renal denervation (RDN) on the recurrence of ventricular arrhythmia (VA) in Asian patients with implantable cardioverter defibrillators (ICDs).Eight ICD patients with recurrent VA episodes underwent RDN using an off-the-shelf saline-irrigated catheter. The pre- and postprocedural VA episodes were counted via ICD interrogation. All patients underwent successful RDN without any complications related to radiofrequency catheter ablation. The median follow-up was 15 months (range 6-30), and the median VA episodes per month were significantly reduced from 3.17 (range 0.33-15.33) to 0.10 (range 0-5.83) after RDN (P < 0.05).RDN is an effective suppressor of VA in Asian patients with ICDs. |
19,601 | Clinical Outcomes in Patients With Nonobstructive, Labile, and Obstructive Hypertrophic Cardiomyopathy. | Hypertrophic cardiomyopathy (HCM) is a common inherited cardiac disease characterized by varying degrees of left ventricular outflow tract obstruction. In a large cohort, we compare the outcomes among 3 different hemodynamic groups.</AbstractText>We prospectively enrolled patients fulfilling standard diagnostic criteria for HCM from January 2005 to June 2015. Detailed phenotypic characterization, including peak left ventricular outflow tract pressure gradients at rest and after provocation, was measured by echocardiography. The primary outcome was a composite cardiovascular end point, which included new-onset atrial fibrillation, new sustained ventricular tachycardia/ventricular fibrillation, new or worsening heart failure, and death. The mean follow-up was 3.4±2.8 years. Among the 705 patients with HCM (mean age, 52±15 years; 62% men), 230 with obstructive HCM were older and had a higher body mass index and New York Heart Association class. The 214 patients with nonobstructive HCM were more likely to have a history of sustained ventricular tachycardia/ventricular fibrillation and implantable cardioverter defibrillator implantation. During follow-up, 121 patients experienced a composite cardiovascular end point. Atrial fibrillation occurred most frequently in the obstructive group. Patients with nonobstructive HCM had more frequent sustained ventricular tachycardia/ventricular fibrillation events. In multivariate analysis, obstructive (hazard ratio, 2.80; 95% confidence interval, 1.64-4.80) and nonobstructive (hazard ratio, 1.94; 95% confidence interval, 1.09-3.45) HCM were associated with more adverse events compared with labile HCM.</AbstractText>Nonobstructive HCM carries notable morbidity, including a higher arrhythmic risk than the other HCM groups. Patients with labile HCM have a relatively benign clinical course. Our data suggest detailed sudden cardiac death risk stratification in nonobstructive HCM and monitoring with less aggressive management in labile HCM.</AbstractText>© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.</CopyrightInformation> |
19,602 | Safety of Intravenous Diltiazem in Reduced Ejection Fraction Heart Failure with Rapid Atrial Fibrillation. | Diltiazem is a nondihydropyridine calcium channel blocker that is used to control rapid ventricular response in patients who have atrial fibrillation or flutter. Diltiazem has a negative inotropic effect and may cause hemodynamic decompensation in patients with reduced ejection fraction. This study evaluated outcomes in patients who had low ejection fraction and were treated with diltiazem.</AbstractText>This was a retrospective chart review in 635 patients who were hospitalized because of rapid atrial fibrillation and who were treated with intravenous diltiazem. Outcomes were evaluated for patients in two groups based on ejection fraction (EF): normal (EF ≥ 50%) and low EF (EF < 50%).</AbstractText>There were no differences in frequency of hypotension, intensive care unit transfer, or in-hospital mortality between the two groups. There was a significantly higher frequency of acute kidney injury within 48 h after starting diltiazem in patients who had low (16 patients [10%]) compared with normal EF (17 patients [3.6%] P = 0.002).</AbstractText>Intravenous diltiazem in patients who have decreased EF may be associated with increased risk of acute kidney injury, but not increased risk of hypotension, intensive care unit transfer, or in-hospital mortality.</AbstractText> |
19,603 | Physical Activity Measured by Implanted Devices Predicts Atrial Arrhythmias and Patient Outcome: Results of IMPLANTED (Italian Multicentre Observational Registry on Patients With Implantable Devices Remotely Monitored). | To determine whether daily physical activity (PA), as measured by implanted devices (through accelerometer sensor), was related to the risk of developing atrial arrhythmias during long-term follow-up in a population of heart failure (HF) patients with an implantable cardioverter defibrillator (ICD).</AbstractText>The study population was divided into 2 equally sized groups (PA cutoff point: 3.5 h/d) according to their mean daily PA recorded by the device during the 30- to 60-day period post-ICD implantation. Propensity score matching was used to compare 2 equally sized cohorts with similar characteristics between lower and higher activity patients. The primary end point was time free from the first atrial high-rate episode (AHRE) of duration ≥6 minutes. Secondary end points were: first AHRE ≥6 hours, first AHRE ≥48 hours, and a combined end point of death or HF hospitalization. Data from 770 patients (65±15 years; 66% men; left ventricular ejection fraction 35±12%) remotely monitored for a median of 25 months were analyzed. A PA ≥3.5 h/d was associated with a 38% relative reduction in the risk of AHRE ≥6 minutes (72-month cumulative survival: 75.0% versus 68.1%; log rank P</i>=0.025), and with a reduction in the risk of AHRE ≥6 hours, AHRE ≥48 hours, and the combined end point of death or HF hospitalization (all P</i><0.05).</AbstractText>In HF patients with ICD, a low level of daily PA was associated with a higher risk of atrial arrhythmias, regardless of the patients' baseline characteristics. In addition, a lower daily PA predicted death or HF hospitalization.</AbstractText>© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.</CopyrightInformation> |
19,604 | Mechanical function of the left atrium is improved with epicardial ligation of the left atrial appendage: Insights from the LAFIT-LARIAT Registry. | Left atrial (LA) strain (ε) and ε rate (SR) analysis by 2-dimensional speckle tracking echocardiography is a novel method for functional assessment of the LA.</AbstractText>The purpose of this study was to determine the impact of left atrial appendage (LAA) exclusion by Lariat epicardial ligation on mechanical function of the LA by performing ε and SR analysis before and after the procedure.</AbstractText>A total of 66 patients who underwent successful LAA exclusion were included in the study. Of these 66 patients, 32 had adequate paired data for ε and SR analysis. SR during ventricular systole (LA-SRs) represents LA reservoir function, and SR during early ventricular diastole (LA-SRe) represents LA conduit function. ε and SR were determined from apical 4- and 2-chamber views using the electrocardiographic QRS as a reference point. LA volume index as surrogate for LA remodeling was measured from apical views.</AbstractText>Mean patient age was 70 ± 9.2 years. LAA ligation resulted in improved reservoir function (LA-SRs: pre 0.72, confidence interval [CI] 0.63-0.83 vs post 0.81, CI 0.73-0.98; P = .043) and conduit function (LA-SRe: pre 0.74, CI 0.67-0.99 vs post 0.89, CI 0.82-1.07; P = .025). LA volume index improved significantly with the Lariat (pre 35.4, CI 29.4-37.2 vs post 29.2, CI 28.2-35.9; P <.023).</AbstractText>LAA exclusion seems to improve mechanical function of the LA and results in reverse LA remodeling.</AbstractText>Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
19,605 | Alternans during fascicular ventricular tachycardia due to digitalis toxicity. | This report describes a digitalis-induced regular fascicular ventricular tachycardia characterized by marked QRS alternans a manifestation not usually associated with this arrhythmia. The striking alternation of QRS configuration suggested alternating ventricular activation from either a single focus with two exits in distal branches of the left anterior fascicle or 2 different foci localized in the Purkinje-myocardial network of the left anterior fascicle. |
19,606 | Impact of digoxin on risk of death in heart failure patients treated with b-blockers. Results from Polish part of ESC Heart Failure Long-Term Registry. | Digoxin is used in the treatment of atrial fibrillation (AF) and heart failure (HF). It was reported to increase the risk of death in HF. Studies on digoxin are based mainly on patients treated some years ago, before the era of common b-blocker use.</AbstractText>This study aims to show the influence of digoxin in a modern cohort of HF patients on top of the contemporary guideline-directed treatment.</AbstractText>This study retrospectively analyses the Polish part of the European Society of Cardiology Heart Failure Long-Term Registry. It includes 912 patients treated for HF between February 2012 and January 2013, and followed until May 2014. At baseline, 19.1% took digoxin, 89.6% angiotensin convertase enzyme inhibitors or angiotensin receptor blockers, 91.9% b-blockers, and 69.4% mineralocorticoid receptor antagonists.</AbstractText>Digoxin is associated with increased risk of death after adjustment for significant covariates in patients who have HF with reduced ejection fraction (HFrEF) but no AF history (hazard ratio [HR] 2.52, 95% confidence interval [CI] 1.23-5.19; p = 0.011), and it does not influence significantly the risk of hospitalisation (adjusted HR 1.46, 95% CI 1.05-1.72; p = 0.11). Digoxin use shows no significant association with the risk of death or hospitalisation in patients with AF and HFrEF or HF with preserved ejection fraction (HFpEF). Patients on digoxin present a significantly worse clinical status with lower left ventricular ejection fraction and higher New York Heart Association class, and fewer of them received the guideline-directed treatment.</AbstractText>Digoxin is associated with increased risk of death in HFrEF patients without AF history receiving the guideline- -directed treatment. Digoxin seems to be employed in patients with worse clinical status, which may at least partially explain its association with increased risk of death.</AbstractText> |
19,607 | Transient left septal fascicular block in the setting of acute coronary syndrome associated with giant slurring variant J-wave. | We report a case of acute coronary syndrome with transient prominent anterior QRS forces (PAF) caused by proximal subocclusion of the left anterior descending (LAD) coronary artery before the first septal perforator branch. The ECG change indicates left septal fascicular block (LSFB) with associated slurring-type giant J-wave. Currently, this J-wave variant is considered as a lambda-like wave or QRS-ST-T "triangulation". Its presence is indicative of poor prognosis because of the risk for cardiac arrest as a consequence of ventricular tachycardia/ventricular fibrillation (VT/VF). |
19,608 | The Influence of Cardiac Pacemaker Programming Modes on Exercise Capacity. | <AbstractText Label="BACKGROUND/AIM">The cardiac pacing mode influences the atrioventricular synchronicity and the response of the heart rate to physical exercise. The aim of this study was to compare the influence of the most common pacemaker programming modes on exercise capacity.</AbstractText>Fifty-two pacemaker-wearing patients were clinically evaluated and submitted to an exercise stress test.</AbstractText>Symptoms of heart failure were more frequently met in the single-chamber pacemaker group compared to the dual-chamber group. The parameters recorded during the exercise stress test were significantly better with the rate responsive function (RRF) activated. The effort time was higher by an average of 2.1 minutes and the exercise capacity was higher by 0.92 metabolic equivalents.</AbstractText>Dual-chamber pacing is superior to single-chamber (ventricular) pacing and the activation of the RRF in single-chamber pacemakers has similar impact on exercise capacity as the preservation of atrioventricular synchronicity by dual-chamber pacemakers.</AbstractText>Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.</CopyrightInformation> |
19,609 | Prospective Randomized Evaluation of Implantable Cardioverter-Defibrillator Programming in Patients With a Left Ventricular Assist Device. | Ventricular arrhythmias are common in patients with left ventricular assist devices (LVADs) but are often hemodynamically tolerated. Optimal implantable cardioverter defibrillator (ICD) tachy-programming strategies in patients with LVAD have not been determined. We sought to determine if an ultra-conservative ICD programming strategy in patients with LVAD affects ICD shocks.</AbstractText>Adult patients with an existing ICD undergoing continuous flow LVAD implantation were randomized to standard ICD programming by their treating physician or an ultra-conservative ICD programming strategy utilizing maximal allowable intervals to detection in the ventricular fibrillation and ventricular tachycardia zones with use of ATP. Patients with cardiac resynchronization therapy (CRT) devices were also randomized to CRT ON or OFF. Patients were followed a minimum of 6 months. The primary outcome was time to first ICD shock. Among the 83 patients studied, we found no statistically significant difference in time to first ICD shock or total ICD shocks between groups. In the ultra-conservative group 16% of patients experienced at least one shock compared with 21% in the control group (P</i>=0.66). There was no difference in mortality, arrhythmic hospitalization, or hospitalization for heart failure. In the 41 patients with CRT ICDs fewer shocks were observed with CRT-ON but this was not statistically significant: 10% of patients with CRT-ON (n=21) versus 38% with CRT-OFF (n=20) received shocks (P</i>=0.08).</AbstractText>An ultra-conservative programming strategy did not reduce ICD shocks. Programming restrictions on ventricular tachycardia and ventricular fibrillation zone therapy should be reconsidered for the LVAD population. The role of CRT in patients with LVAD warrants further investigation.</AbstractText>URL: https://www.clinicaltrials.gov. Unique identifier: NCT01977703.</AbstractText>© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.</CopyrightInformation> |
19,610 | Increased Susceptibility for Atrial and Ventricular Cardiac Arrhythmias in Mice Treated With a Single High Dose of Ibrutinib. | Atrial fibrillation is a side effect of ibrutinib, an irreversible inhibitor of Bruton tyrosine kinase used for treatment of B-cell lymphoproliferative disorders. We determined if single (2 or 10 mg/kg), or chronic (14 days) oral ibrutinib followed by 24-hour washout conferred susceptibility to electrically induced arrhythmias in 1-month-old male C57BL/6 mice. A single higher dose of ibrutinib increased arrhythmia inducibility. There was no inducibility difference after chronic dosing with washout. This suggests that high serum drug levels might be responsible for the proarrhythmic effect of ibrutinib and that an altered dosing strategy might mitigate the side effects. |
19,611 | 2018 Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology Focused Update of the Guidelines for the Use of Antiplatelet Therapy. | Antiplatelet therapy (APT) has become an important tool in the treatment and prevention of atherosclerotic events, particularly those associated with coronary artery disease. A large evidence base has evolved regarding the relationship between APT prescription in various clinical contexts and risk/benefit relationships. The Guidelines Committee of the Canadian Cardiovascular Society and Canadian Association of Interventional Cardiology publishes regular updates of its recommendations, taking into consideration the most recent clinical evidence. The present update to the 2011 and 2013 Canadian Cardiovascular Society APT guidelines incorporates new evidence on how to optimize APT use, particularly in situations in which few to no data were previously available. The recommendations update focuses on the following primary topics: (1) the duration of dual APT (DAPT) in patients who undergo percutaneous coronary intervention (PCI) for acute coronary syndrome and non-acute coronary syndrome indications; (2) management of DAPT in patients who undergo noncardiac surgery; (3) management of DAPT in patients who undergo elective and semiurgent coronary artery bypass graft surgery; (4) when and how to switch between different oral antiplatelet therapies; and (5) management of antiplatelet and anticoagulant therapy in patients who undergo PCI. For PCI patients, we specifically analyze the particular considerations in patients with atrial fibrillation, mechanical or bioprosthetic valves (including transcatheter aortic valve replacement), venous thromboembolic disease, and established left ventricular thrombus or possible left ventricular thrombus with reduced ejection fraction after ST-segment elevation myocardial infarction. In addition to specific recommendations, we provide values and preferences and practical tips to aid the practicing clinician in the day to day use of these important agents. |
19,612 | A novel mutation of dipeptidyl aminopeptidase-like protein-6 in a family with suspicious idiopathic ventricular fibrillation. | Sudden cardiac death (SCD) occurs in a broad spectrum of cardiac pathologies and is an important cause of mortality in the general population. Idiopathic ventricular fibrillation (IVF) is a rare but important factor resulting in SCD. It is diagnosed in a resuscitated cardiac arrest victim underlying unknown cause, with documented ventricular fibrillation. Previous studies have demonstrated that mutations in dipeptidyl aminopeptidase-like protein-6 (DPP6) and cardiac sodium channel Nav1.5 (SCN5A) are the most important genetic factors involve in IVF.</AbstractText>By using whole sequencing to identify the genetic lesion of a family with suspicious idiopathic ventricular fibrillation.</AbstractText>Prospective genetic study.</AbstractText>In this study, we employed whole-exome sequencing in combination with arrhythmia-related gene filtering to identify the genetic lesion for a family suffering from suspicious IVF, syncope and SCD. We then generated the plasmids of DPP6-pcDNA3.1+ (WT and c.1578G>C/p.Q526H). Kv4.3-pcDNA3.1+ was co-transfected together with/without DPP6-pcDNA3.1+ (WT and/or c.1578G>C/p.Q526H) into HEK293 cells to perform the patch clamp experiments.</AbstractText>A novel missense mutation (c.1578G>C/p.Q526H) of DPP6 was identified and co-segregated with affected patients in this family. Patch clamp experiments suggested that this novel mutation might result in a gain of function and disturb the efflux of potassium ion.</AbstractText>Our study not only reported the second missense mutation of DPP6 in heart disease and expanded the spectrum of DPP6 mutations, but also contribute to the genetic diagnosis and counseling of families with suspicious IVF, syncope and SCD.</AbstractText> |
19,613 | Rationale and design of the EACVI AFib Echo Europe Registry for assessing relationships of echocardiographic parameters with clinical thrombo-embolic and bleeding risk profile in non-valvular atrial fibrillation. | The European Society of Cardiology (ESC) guidelines for management of atrial fibrillation (AF) recommend the use of CHA2DS2VASc risk score for assessment of thromboembolic (TE) risk, whereas the stratification of bleeding risk should be obtained by HAS-Bleed to balance the most appropriate anticoagulation (OAC) therapy. However, men with CHA2DS2VASc score = 1 and women with CHA2DS2VASc = 2, who are at intermediate TE risk, represent a grey zone where guidelines do not provide a definite OAC indication. Accordingly, implementation of risk stratification with echocardiography could be extremely useful. Both prospective and cross-sectional studies on transthoracic echocardiography (TTE) prediction of TE events and studies utilizing transoesophageal echocardiographic parameters as surrogate markers of TE events makes sustainable the hypothesis that echocardiography could improve TE prediction in non-valvular AF. Moreover, considering the close association of AF and stroke, all echo-Doppler parameters that have shown to predict AF onset and recurrence could be useful also to predict TE events in this clinical setting. Accordingly, EACVI AFib Echo Europe Registry has been designed as an observational, cross-sectional study, with the aim of evaluating: (i) left atrial (LA) size and function together with left ventricular geometry, systolic and diastolic functions in paroxysmal, persistent, and permanent AF; (ii) relationships of structural/functional parameters with clinical TE and bleeding risk profile. By the AFib Echo Europe Registry, we expect to collect data on echocardiographic phenotype of patients with AF. The large data set accumulated will be useful to test the level of agreement of different echocardiographic measurements with the available risk scores. |
19,614 | Facilitation of ischaemia-induced ventricular fibrillation by catecholamines is mediated by β<sub>1</sub> and β<sub>2</sub> agonism in the rat heart in vitro. | Antiarrhythmic β-blockers are used in patients at risk of myocardial ischaemia, but the survival benefit and mechanisms are unclear. We hypothesized that β-blockers do not prevent ventricular fibrillation (VF) but instead inhibit the ability of catecholamines to facilitate ischaemia-induced VF, limiting the scope of their usefulness.</AbstractText>ECGs were analysed from ischaemic Langendorff-perfused rat hearts perfused with adrenoceptor antagonists and/or exogenous catecholamines (CATs: 313 nM noradrenaline + 75 nM adrenaline) in a blinded and randomized study. Ischaemic zone (IZ) size was deliberately made small or large.</AbstractText>In rat hearts with large IZs, ischaemia-induced VF incidence was high in controls. Atenolol, butoxamine and trimazosin did not affect VF at concentrations with β1</sub> -, β2</sub> - or α1</sub> - adrenoceptor specificity and selectivity (confirmed in separate rat aortae myography experiments). In hearts with small IZs and low baseline incidence of ischaemia-induced VF, CATs, delivered to the uninvolved zone (UZ), increased ischaemia-induced VF incidence. This effect was not mimicked by atrial pacing, hence, not due to sinus tachycardia. However, the CATs-facilitated increase in ischaemia-induced VF was inhibited by atenolol and butoxamine (but not trimazosin), indicative of β1</sub> - and β2</sub> - but not α1</sub> -adrenoceptor involvement (confirmed by immunoblot analysis of downstream phosphoproteins). CATs did not facilitate VF in low-flow globally ischaemic hearts, which have no UZ.</AbstractText>Catecholamines facilitated ischaemia-induced VF when risk was low, acting via β1</sub> - and β2</sub> - adrenoceptors located in the UZ. There was no scope for facilitation when VF risk was high (large IZ), which may explain why β-blockers have equivocal effectiveness in humans.</AbstractText>© 2018 The British Pharmacological Society.</CopyrightInformation> |
19,615 | Landiolol: A Review in Tachyarrhythmias. | Intravenous landiolol [Rapibloc<sup>®</sup> (EU)], an ultra short-acting highly cardioselective β<sub>1</sub>-blocker, is approved in the EU for the rapid short-term control of tachyarrhythmias in the perioperative and intensive care settings. It has long been used in Japan to treat perioperative tachyarrhythmias. The efficacy of landiolol has been demonstrated in a large number of randomized controlled clinical trials. Landiolol significantly reduced heart rate in patients with postoperative or intraoperative supraventricular tachycardia relative to placebo and in those with atrial fibrillation/flutter and left ventricular dysfunction relative to digoxin. It was more effective than diltiazem in converting postoperative atrial fibrillation (POAF) to normal sinus rhythm. Perioperative prophylactic administration of landiolol significantly reduced the incidence of POAF during the first week after cardiac and other surgeries, compared with diltiazem, placebo or no landiolol treatment. Landiolol also attenuated adverse haemodynamic and other responses to invasive procedures such as percutaneous coronary intervention, tracheal intubation, extubation and electroconvulsive therapy. Landiolol was generally well tolerated, with a relatively low risk of hypotension and bradycardia. Landiolol has more favourable pharmacological properties than esmolol, a short-acting β-blocker commonly used for the rapid control of heart rate. Although additional comparative studies are warranted to define the place of landiolol relative to esmolol, current evidence suggest that landiolol is a useful option for the rapid short-term control of tachyarrhythmias. Landiolol offers a simple dosage scheme and is available in two easy-to-use formulations (concentrate and powder). |
19,616 | Clinically oriented device programming in bradycardia patients: part 2 (atrioventricular blocks and neurally mediated syncope). Proposals from AIAC (Italian Association of Arrhythmology and Cardiac Pacing). | : The purpose of this two-part consensus document is to provide specific suggestions (based on an extensive literature review) on appropriate pacemaker setting in relation to patients' clinical features. In part 2, criteria for pacemaker choice and programming in atrioventricular blocks and neurally mediate syncope are proposed. The atrioventricular blocks can be paroxysmal or persistent, isolated or associated with sinus node disease. Neurally mediated syncope can be related to carotid sinus syndrome or cardioinhibitory vasovagal syncope. In sinus rhythm, with persistent atrioventricular block, we considered appropriate the activation of mode-switch algorithms, and algorithms for auto-adaptive management of the ventricular pacing output. If the atrioventricular block is paroxysmal, in addition to algorithms mentioned above, algorithms to maximize intrinsic atrioventricular conduction should be activated. When sinus node disease is associated with atrioventricular block, the activation of rate-responsive function in patients with chronotropic incompetence is appropriate. In permanent atrial fibrillation with atrioventricular block, algorithms for auto-adaptive management of the ventricular pacing output should be activated. If the atrioventricular block is persistent, the activation of rate-responsive function is appropriate. In carotid sinus syndrome, adequate rate hysteresis should be programmed. In vasovagal syncope, specialized sensing and pacing algorithms designed for reflex syncope prevention should be activated. |
19,617 | Right Ventricular Dysfunction and Its Contribution to Morbidity and Mortality in Left Ventricular Heart Failure. | In patients with left-sided HF, there has been less emphasis on the pathophysiology of the RV in terms of diagnostic evaluation and treatment, versus focus on structural abnormalities of the LV. This review seeks to delineate the importance of RV dysfunction in terms of its contribution to symptomatic limitations and cardiovascular outcomes in patients with left-sided HF.</AbstractText>Recent studies have demonstrated that RV dysfunction is common in both HFpEF and HFrEF, but more pronounced in HFrEF. LV dysfunction and atrial fibrillation are most commonly associated with RV dysfunction in left-sided HF. RV dysfunction may develop due to afterload-dependent and afterload-independent pathways. Regardless, RV dysfunction is strongly associated with functional limitations and worsened survival in patients with left-sided HF. In patients with HFpEF, a recent study showed that RV failure was the most common cause of overall mortality. Among LVAD patients and patients post-cardiac transplantation, RV dysfunction is also strongly associated with survival. Despite a number of previous and ongoing clinical trials that target the RV directly or decrease RV afterload in left-sided HF, there are no definitive therapies specifically targeting RV dysfunction in left-sided HF patients CONCLUSIONS: RV dysfunction is an important determinant of symptomatic limitations and cardiovascular outcomes in patients with left-sided HF. Further research is needed to developed pharmacotherapy that may target the RV specifically in left-sided HF patients.</AbstractText> |
19,618 | Intermuscular implantation technique for subcutaneous cardioverter-defibrillators. | The conventional technique for subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation has been associated with pocket complications. The aim of this study was to evaluate the efficacy and safety of an alternative intermuscular technique for S‑ICD implantation.</AbstractText>S-ICDs were implanted in ten consecutive patients (ten males, mean age: 46.8 ± 14.7 years). The pocket for the pulse generator was made above the serratus anterior muscular fascia and beneath the latissimus dorsi muscle by detaching the fibrous tissue between the muscles. Electrode implantation was performed using the three- (n = 4) or the two-incision technique (n = 6).</AbstractText>All S‑ICDs were successfully implanted in the absence of any procedure-related complications with a successful 65-J standard polarity defibrillation threshold testing, apart from one patient with Brugada syndrome who needed device repositioning more dorsally. During a mean follow-up of 16.5 ± 7.3 months, no major complications requiring surgical repair were encountered, while patients demonstrated high levels of comfort and satisfaction with the cosmetic result. One patient experienced an inappropriate shock due to noise detection, which was resolved after reprogramming to a different sensing vector.</AbstractText>The intermuscular technique is a safe and efficacious approach for S‑ICD implantation. This technique could lead to fewer pocket-related complications and better cosmetic results.</AbstractText> |
19,619 | Cholecystokinin octapeptide inhibits the inflammatory response and improves neurological outcome in a porcine model of cardiopulmonary resuscitation. | Previous studies have demonstrated that cholecystokinin octapeptide (CCK8) induces hypothermia and inhibits the systemic inflammatory response in septic shock in rat and murine models. The present study aimed to ascertain whether CCK8 induced hypothermia and improved the neurological outcomes in a porcine model of cardiopulmonary resuscitation (CPR). Ventricular fibrillation was induced and left untreated for 10 min in 12 male Bama miniature pigs. Defibrillation was attempted after 5 min of CPR. At 5 min following resuscitation, the pigs were randomized and equally assigned into the CCK8 or the control group. CCK8 was continuously infused for 1 h at a dose of 44.4 µg/kg/h and a rate of 20 ml/h in the CCK8 group. Body temperature, hemodynamic measurements and post-resuscitation myocardial function were monitored in the first 4 h following CPR. Neuron specific enzyme (NSE), S100B protein, tumor necrosis factor (TNF)-α and interleukin (IL)-6 were measured at baseline and 4, 12 and 24 h following resuscitation. The neurological deficient score (NDS) was recorded and cerebral samples were collected for terminal deoxynucleotidyl-transferase-mediated dUTP nick end labelling assay and integrated optical density (IOD) analysis at 24 h following CPR. The results revealed that hypothermia was not induced by CCK8; however, post-resuscitation NSE, S100B, IL-6 and TNF-α were significantly decreased, and NDS and IOD were significantly improved in the CCK8 group compared with the control group (P<0.05). The present study revealed that in a porcine model of CPR, CCK8 does not induce hypothermia, but inhibits the inflammatory response and significantly improves neurological outcomes. |
19,620 | Electromechanical vortex filaments during cardiac fibrillation. | The self-organized dynamics of vortex-like rotating waves, which are also known as scroll waves, are the basis of the formation of complex spatiotemporal patterns in many excitable chemical and biological systems. In the heart, filament-like phase singularities that are associated with three-dimensional scroll waves are considered to be the organizing centres of life-threatening cardiac arrhythmias. The mechanisms that underlie the onset, maintenance and control of electromechanical turbulence in the heart are inherently three-dimensional phenomena. However, it has not previously been possible to visualize the three-dimensional spatiotemporal dynamics of scroll waves inside cardiac tissues. Here we show that three-dimensional mechanical scroll waves and filament-like phase singularities can be observed deep inside the contracting heart wall using high-resolution four-dimensional ultrasound-based strain imaging. We found that mechanical phase singularities co-exist with electrical phase singularities during cardiac fibrillation. We investigated the dynamics of electrical and mechanical phase singularities by simultaneously measuring the membrane potential, intracellular calcium concentration and mechanical contractions of the heart. We show that cardiac fibrillation can be characterized using the three-dimensional spatiotemporal dynamics of mechanical phase singularities, which arise inside the fibrillating contracting ventricular wall. We demonstrate that electrical and mechanical phase singularities show complex interactions and we characterize their dynamics in terms of trajectories, topological charge and lifetime. We anticipate that our findings will provide novel perspectives for non-invasive diagnostic imaging and therapeutic applications. |
19,621 | [Structural and Functional Properties of the Left Atrium in Healthy Volunteers and Patients With Atrial Fibrillation: Data of Magnetic Resonance Imaging]. | in the recent years, there has been an increasing number of publications postulating that data on left atrial (LA) structure obtained by late gadolinium enhancement magnetic resonance imaging (LGE MRI) can improve the management of patients with atrial fibrillation (AF). At the same time, similar data regarding healthy LA myocardium is limited.</AbstractText>to assess structural and functional properties of LA in healthy volunteers (HV) using cardiac magnetic resonance (CMR) (including LGE MRI); to compare these properties in patients with AF and HV.</AbstractText>We included in this study 53 patients with AF (28 without signs of cardiovascular disease, 28 with hypertension) and 23 HV of similar age. All enrolled persons underwent MRI. Cine-MRI was used to assess end diastolic volume of LA (LA EDV), LA ejection fraction (LA EF), left ventricular diastolic index (LV DI). High resolution LGE MRI was performed 15-20 min after gadoversetamide injection using IR 3D gradient echo pulse sequence with fat saturation (TI 290-340 ms, TE 2.44 ms, TR 610-1100ms). On obtained images LA was segmented semiautomatically. LA fibrosis quantification was performed using developed software LGE Heart Analyzer. The extent of fibrosis was represented as percent of LA myocardium volume. Fibrosis location was determined on reconstructed rotating 3D LA model.</AbstractText>Compared with patients HV had lower LA EDV (59 [54; 78] ml and 79 [65.5; 86.6] ml, р=0.043, respectively), higher LA EF (56.1 [49; 63.2] % and 44.5 [34.5, 54.5] %, р=0.03, respectively), and lower extent of LA fibrosis (0.7 [0.05; 3.5] % and 9.1 [1.7; 18] %, р.</AbstractText> |
19,622 | [Elevated Level of the Natriuretic Peptide Among Adult Population in Regions Participating in the ESSE-RF Study and Its Association With Cardiovascular Diseases and Risk Factors]. | to study associations between elevated blood plasma concentration of N-terminal pro-brain natriuretic peptide (NT-proBNP), risk factors and cardiovascular diseases (CVD) in samples of adult population of Russian Federation (RF) aged 25-64 years.</AbstractText>We analyzed data of examination of representative samples of population of 5 regions of RF obtained within the framework of the multicenter ESSE-RF study (2012-2013). Number of examined subjects was 8 077 (3 176 men). Methods included use of standard questionnaire, measurements of height, body mass, blood pressure (BP), and plasma NT-proBNP level. The following CVD were included into analysis: arterial hypertension (AH), ischemic heart disease (IHD), atrial fibrillation (AF), and stroke.</AbstractText>Women compared to men had higher NT-proBNT concentration was higher in women compared to men, in both genders it rose with age. Overall 17.9 % of examinees had elevated NT-proBNT levels (14.2 and 20.3 % among men and women, respectively). Elevated NTproBNP level was associated in men with age, myocardial infarction, angina pectoris, ischemic ECG changes, left ventricular hypertrophy, AF, bradycardia, smoking, in women with age, IHD, ischemic ECG changes, AF, bradycardia, heart rate ≥80 bpm, BP ≥160/95 mm Hg.</AbstractText>In studied RF population elevated NT-proBNP level was significantly associated with gender, age, smoking, and CVD.</AbstractText> |
19,623 | [Interventional treatment in patients with myocarditis: Pro and Contra].<Pagination><StartPage>49</StartPage><EndPage>56</EndPage><MedlinePgn>49-56</MedlinePgn></Pagination><Abstract><AbstractText Label="AIM">Ventricular tachyarrhythmias (VTs) are often encountered in patients with inflammatory heart diseases. VT can become lifethreatening in patients with myocarditis, and the management may vary in different types of myocarditis. Purpose of the study is to describe VT characteristics in patients with verified myocarditis, and to evaluate the efficacy and safety of VT management, when tailored to the type of myocarditis.</AbstractText><AbstractText Label="MATERIALS AND METHODS">Study population comprised: 56 patients with morphologically verified myocarditis; 18 patients with primary cardiomyopathy (control group). All patients underwent full clinical evaluation, endomyocardial biopsy (including immunohistochemical analysis). Forty (54 %) patients underwent radiofrequency catheter ablation of VT. An implantable cardioverter-defibrillator (ICD) was inserted in 17 patients.</AbstractText><AbstractText Label="RESULTS">There was no statistically significant difference between myocarditis and primary cardiomyopathy groups by demographic and echocardiographic data. In myocarditis group, nonsustained VT and/or frequent premature ventricular beats were seen in 59 % of patients; sustained VT in 12,5 % subjects, 1 patient had a history of ventricular fibrillation. VT ablation was associated with a significant decrease in VT recurrence (p=0,0009) during the follow-up period. Active myocarditis was associated with a higher VT recurrence rate (67 % in active vs. 19 % in borderline myocarditis). Among patients with ICD implantation, only one subject (with active myocarditis at admission) had life-threatening ventricular arrhythmia.</AbstractText><AbstractText Label="CONCLUSION">In this selected group of patients with verified myocarditis and clinically significant VTs, catheter ablation seems at least partly effective. Patients with borderline myocarditis and symptomatic VTs may benefit from ablation. Therefore, morphological diagnostic of myocarditis can be a key point in choice of treatment.</AbstractText></Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Syrovnev</LastName><ForeName>V A</ForeName><Initials>VA</Initials><AffiliationInfo><Affiliation>Federal State Budgetary Institution "Federal Almazov North-West Medical Research Center" of the Ministry of Health of the Russian Federation.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Lebedev</LastName><ForeName>D S</ForeName><Initials>DS</Initials><AffiliationInfo><Affiliation>Federal State Budgetary Institution "Federal Almazov North-West Medical Research Center" of the Ministry of Health of the Russian Federation.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Mitrofanova</LastName><ForeName>L B</ForeName><Initials>LB</Initials><AffiliationInfo><Affiliation>Federal State Budgetary Institution "Federal Almazov North-West Medical Research Center" of the Ministry of Health of the Russian Federation.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Lebedeva</LastName><ForeName>V K</ForeName><Initials>VK</Initials><AffiliationInfo><Affiliation>Federal State Budgetary Institution "Federal Almazov North-West Medical Research Center" of the Ministry of Health of the Russian Federation.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Tatarskiy</LastName><ForeName>R B</ForeName><Initials>RB</Initials><AffiliationInfo><Affiliation>Federal State Budgetary Institution "Federal Almazov North-West Medical Research Center" of the Ministry of Health of the Russian Federation.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Mikhaylov</LastName><ForeName>E N</ForeName><Initials>EN</Initials><AffiliationInfo><Affiliation>Federal State Budgetary Institution "Federal Almazov North-West Medical Research Center" of the Ministry of Health of the Russian Federation.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Moiseeva</LastName><ForeName>O M</ForeName><Initials>OM</Initials><AffiliationInfo><Affiliation>Federal State Budgetary Institution "Federal Almazov North-West Medical Research Center" of the Ministry of Health of the Russian Federation.</Affiliation></AffiliationInfo></Author></AuthorList><Language>rus</Language><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType></PublicationTypeList></Article><MedlineJournalInfo><Country>Russia (Federation)</Country><MedlineTA>Kardiologiia</MedlineTA><NlmUniqueID>0376351</NlmUniqueID><ISSNLinking>0022-9040</ISSNLinking></MedlineJournalInfo><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D000328" MajorTopicYN="N">Adult</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D001145" MajorTopicYN="N">Arrhythmias, Cardiac</DescriptorName><QualifierName UI="Q000150" MajorTopicYN="N">complications</QualifierName><QualifierName UI="Q000628" MajorTopicYN="N">therapy</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D017115" MajorTopicYN="Y">Catheter Ablation</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D017147" MajorTopicYN="Y">Defibrillators, Implantable</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D005260" MajorTopicYN="N">Female</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D006801" MajorTopicYN="N">Humans</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008297" MajorTopicYN="N">Male</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008875" MajorTopicYN="N">Middle Aged</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D009205" MajorTopicYN="N">Myocarditis</DescriptorName><QualifierName UI="Q000150" MajorTopicYN="N">complications</QualifierName><QualifierName UI="Q000503" MajorTopicYN="N">physiopathology</QualifierName><QualifierName UI="Q000628" MajorTopicYN="Y">therapy</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D017180" MajorTopicYN="N">Tachycardia, Ventricular</DescriptorName><QualifierName UI="Q000150" MajorTopicYN="N">complications</QualifierName><QualifierName UI="Q000628" MajorTopicYN="N">therapy</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D016896" MajorTopicYN="N">Treatment Outcome</DescriptorName></MeshHeading></MeshHeadingList><KeywordList Owner="NOTNLM"><Keyword MajorTopicYN="N">ventricular rhythm disorder, sudden cardiac death, dilated cardiomyopathy, endomyocardial biopsy, implantable cardioverter-defibrillator, radiofrequency ablation</Keyword></KeywordList></MedlineCitation><PubmedData><History><PubMedPubDate PubStatus="entrez"><Year>2018</Year><Month>2</Month><Day>22</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="pubmed"><Year>2018</Year><Month>2</Month><Day>22</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="medline"><Year>2019</Year><Month>3</Month><Day>6</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate></History><PublicationStatus>ppublish</PublicationStatus><ArticleIdList><ArticleId IdType="pubmed">29466189</ArticleId><ArticleId IdType="doi">10.18087/cardio.2405</ArticleId></ArticleIdList></PubmedData></PubmedArticle><PubmedArticle><MedlineCitation Status="MEDLINE" Owner="NLM" IndexingMethod="Curated"><PMID Version="1">29466170</PMID><DateCompleted><Year>2019</Year><Month>05</Month><Day>20</Day></DateCompleted><DateRevised><Year>2019</Year><Month>11</Month><Day>13</Day></DateRevised><Article PubModel="Print"><Journal><ISSN IssnType="Print">0022-9040</ISSN><JournalIssue CitedMedium="Print"><Issue>1</Issue><PubDate><Year>2018</Year><Month>Jan</Month></PubDate></JournalIssue><Title>Kardiologiia</Title><ISOAbbreviation>Kardiologiia</ISOAbbreviation></Journal>[Phenomenological Regularities of Assessment of Left Ventricle Function in Mitral Valve Insufficiency]. | Ventricular tachyarrhythmias (VTs) are often encountered in patients with inflammatory heart diseases. VT can become lifethreatening in patients with myocarditis, and the management may vary in different types of myocarditis. Purpose of the study is to describe VT characteristics in patients with verified myocarditis, and to evaluate the efficacy and safety of VT management, when tailored to the type of myocarditis.</AbstractText>Study population comprised: 56 patients with morphologically verified myocarditis; 18 patients with primary cardiomyopathy (control group). All patients underwent full clinical evaluation, endomyocardial biopsy (including immunohistochemical analysis). Forty (54 %) patients underwent radiofrequency catheter ablation of VT. An implantable cardioverter-defibrillator (ICD) was inserted in 17 patients.</AbstractText>There was no statistically significant difference between myocarditis and primary cardiomyopathy groups by demographic and echocardiographic data. In myocarditis group, nonsustained VT and/or frequent premature ventricular beats were seen in 59 % of patients; sustained VT in 12,5 % subjects, 1 patient had a history of ventricular fibrillation. VT ablation was associated with a significant decrease in VT recurrence (p=0,0009) during the follow-up period. Active myocarditis was associated with a higher VT recurrence rate (67 % in active vs. 19 % in borderline myocarditis). Among patients with ICD implantation, only one subject (with active myocarditis at admission) had life-threatening ventricular arrhythmia.</AbstractText>In this selected group of patients with verified myocarditis and clinically significant VTs, catheter ablation seems at least partly effective. Patients with borderline myocarditis and symptomatic VTs may benefit from ablation. Therefore, morphological diagnostic of myocarditis can be a key point in choice of treatment.</AbstractText> |
19,624 | Device Thrombosis After Percutaneous Left Atrial Appendage Occlusion Is Related to Patient and Procedural Characteristics but Not to Duration of Postimplantation Dual Antiplatelet Therapy. | Device-related thrombus (DRT) after left atrial appendage occlusion is a worrisome finding with little knowledge about when to expect it and how to prevent it. This study sought to investigate correlates of DRT after left atrial appendage occlusion, its time of diagnosis, and particularly, association with postimplantation dual antiplatelet therapy duration.</AbstractText>Consecutive patients (n=102) after left atrial appendage occlusion with AMPLATZER Cardiac Plug/Amulet (n=59) or WATCHMAN (n=43) were included in a prospective registry (October 2011-May 2016). Follow-up was done at 1.5, 3 to 6, and 12 months postimplantation. DRT was classified as early (at 1.5 month), late (at 3-6 month), or very late (at 12-month follow-up). Postimplantation dual antiplatelet therapy was recommended for 30 to 180 days and decided independently by attending physicians. Final analysis included 99 patients, 42 (42.4%) females, with median CHA2</sub>DS2</sub>-VASc of 4.0 (interquartile range [IQR], 3.0-5.0) and median HAS-BLED score of 2.0 (IQR, 1.0-3.0). DRTs were observed in 7 (7.1%) patients: 2 (28.6%) early, 2 (28.6%) late, and 3 (42.9%) very late. When compared with patients without DRT, those with DRT presented more often with a history of prior thromboembolism (5 [71.4%] versus 28 [30.4%]; P</i>=0.04), had lower left ventricular ejection fraction (50.0 [IQR, 35.0-55.0] versus 60.0 [IQR, 55.0-66.0]; P</i><0.01), and had greater proportion of patients with deep device implantation (6 [85.7%] versus 36 [39.1%]; P</i>=0.04) and with larger devices implanted (30.0 mm [IQR, 27.0-33.0] versus 25.0 mm [IQR, 24.0-28.0]; P</i><0.01). Postimplantation dual antiplatelet therapy duration was not different between the 2 groups (12.4 weeks [IQR, 6.0-49.7] with DRT versus 13.0 weeks [IQR, 7.3-26.0] without DRT; P</i>=0.77).</AbstractText>In this real-world series, DRT was observed early, late, and very late after left atrial appendage occlusion. It was related to patient and procedural characteristics but not to postimplantation dual antiplatelet therapy duration.</AbstractText>© 2018 American Heart Association, Inc.</CopyrightInformation> |
19,625 | Ventricular Fibrillation Conversion Testing After Implantation of a Subcutaneous Implantable Cardioverter Defibrillator: Report From the National Cardiovascular Data Registry. | Compared with transvenous implantable cardioverter defibrillators (ICDs), subcutaneous (S)-ICDs require a higher energy for effective defibrillation. Although ventricular fibrillation conversion testing (CT) is recommended after S-ICD implantation to ensure an adequate margin between the defibrillation threshold and maximum device output (80J), prior work found that adherence to this recommendation is declining.</AbstractText>We studied first-time recipients of S-ICDs (between September 28, 2012, and April 1, 2016) in the National Cardiovascular Database Registry ICD Registry to determine predictors of use of CT, predictors of an insufficient safety margin (ISM, defined as ventricular fibrillation conversion energy >65J) during testing, and inhospital outcomes associated with use of CT. Multivariable logistic regression analysis was used to predict use of CT and ISM. Inverse probability weighted logistic regression analysis was used to examine the association between use of CT and inhospital adverse events including death.</AbstractText>CT testing was performed in 70.7% (n=5624) of 7960 patients with S-ICDs. Although deferral of CT was associated with several patient characteristics (including increased body mass index, increased body surface area, severely reduced ejection fraction, dialysis dependence, warfarin use, anemia, and hypertrophic cardiomyopathy), the facility effect was comparatively more important (area under the curve for patient level versus generalized linear mixed model: 0.619 versus 0.877). An ISM occurred in 6.9% (n=336) of 4864 patients without a prior ICD and was more common among white patients and those with ventricular pacing on the preimplant ECG, higher preimplant blood pressure, larger body surface area, higher body mass index, and lower ejection fraction. A risk score was able to identify patients at low (<5%), medium (5% to 10%), and high risk (>10%) for ISM. CT testing was not associated with a composite of inhospital complications including death.</AbstractText>Use of CT testing after S-ICD implantation was driven by facility preference to a greater extent than patient factors and was not associated with a composite of inhospital complications or death. ISM was relatively uncommon and is associated with several widely available patient characteristics. These data may inform ICD system selection and a targeted approach to CT.</AbstractText>© 2018 American Heart Association, Inc.</CopyrightInformation> |
19,626 | Assessment of atrial fibrillation and ventricular arrhythmia risk in patients with asthma by P wave/corrected QT interval dispersion. | Although the relationship between obesity-asthma, obesity-atrial fibrillation (AF) and obesity-sudden cardiac death is clearly known, the risk of AF and ventricular arrhythmia has not been clearly determined in asthmatic patients. The aim of this study was to investigate whether AF, ventricular arrhythmia, and sudden cardiac death risk were increased in asthmatic patients using P wave dispersion (PWD) and corrected QT interval dispersion (CQTD).</AbstractText>The study was designed as a cross-sectional study. A total of 164 participants (88 patients with asthma and 76 healthy volunteers) were enrolled into the study. PWD and CQTD were measured and recorded in both groups. The statistical difference between the two groups was examined.</AbstractText>PWD was higher in the asthma patients than in control subjects (31.53 ± 3.18 vs. 30.33 ± 3.53, p = 0.023). However, there was no statistically difference between the groups in terms of CQTD measurement (43.9 ± 1.84 vs. 43.63 ± 2.06, p = 0.385). In comparison between control group and asthma subgroups (mild, moderate and severe), there was a statistically significant difference among these four groups in terms of PWD (p = 0.017). Subgroup analyses showed that this difference was mainly due to patients with severe asthma.</AbstractText>PWD value was elevated in asthmatic compared to the control group. The CQTD was not statistically significant between the groups. These results indicate that the risk of developing AF in asthmatic patients might be higher than in the normal population. Ventricular arrhythmia and sudden cardiac death risk may not be high in asthmatic patients.</AbstractText> |
19,627 | Evaluation of sex differences in the relationship between diastolic dysfunction and thromboembolism using propensity score analysis. | Female sex is a risk factor for thromboembolism (TE) in atrial fibrillation (AF); however, the underlying mechanisms are unclear. We postulated that left ventricular (LV) diastolic dysfunction (LVDD) could be associated with increased thromboembolic risk in women.</AbstractText>From a retrospective cohort, 158 patients (female : male = 79:79) with nonvalvular AF were propensity score-matched for age, presence of diabetes, hypertension, coronary artery disease, congestive heart failure, embolic history, AF type, and AF duration. Cardiac size and function and central aortic stiffness parameters were evaluated. Diastolic function was classified as normal, indeterminate, and LVDD according to recent guidelines. Surrogate markers for thromboembolism (dense spontaneous echo contrast and thrombus) were evaluated using transesophageal echocardiography.</AbstractText>Surrogate markers for TE showed a trend to be more frequent in women than in men (21.5% vs 11.4%, P = .086). LVDD was more prevalent in women than in men (22.8% vs 2.5%, P < .001); however, the prevalence of indeterminate diastolic function was not different between sexes (26.6% vs 20.3%, P = .453). Surrogate markers for TE were detected mostly in women with LVDD. LV diastolic parameters showed a restrictive pattern, and aortic stiffness parameters were worse in women than in men. Women with LVDD had increased aortic stiffness compared to women with indeterminate and normal function, whereas aortic stiffness did not differ among men in all groups. Significant relations between LV diastolic function and aortic stiffness parameters were observed only in women.</AbstractText>LVDD due to increased aortic stiffness could be related to a higher thromboembolic risk in women with AF.</AbstractText>© 2018 Wiley Periodicals, Inc.</CopyrightInformation> |
19,628 | A double-blind, randomised, placebo-controlled, cross-over study assessing the use of XEN-D0103 in patients with paroxysmal atrial fibrillation and implanted pacemakers allowing continuous beat-to-beat monitoring of drug efficacy. | The ultrarapid delayed rectifier current (IKur</sub>) carried by Kv1.5 channels, which are solely expressed in the atrium, is a potential target for safer treatment of paroxysmal atrial fibrillation (PAF). XEN-D0103 is a nanomolar ion channel blocker that selectively inhibits potassium ion flux through the Kv1.5 ion channel. The efficacy of XEN-D0103 in reducing AF burden was assessed in patients with DDDRp permanent pacemakers (PPMs) and PAF.</AbstractText>A double-blind, placebo-controlled, cross-over study was performed in patients with PAF and DDDRp PPMs with advanced atrial and ventricular Holters allowing beat-to-beat arrhythmia follow-up. All anti-arrhythmic drugs were withdrawn before randomised treatment. After baseline assessment, patients were randomly assigned to two treatment periods of placebo then XEN-D0103 50 mg bd, or XEN-D0103 50 mg bd then placebo.</AbstractText>Fifty-four patients were screened and 21 patients were eligible and included in the randomised trial. All 21 patients completed both treatment periods. The primary endpoint was change in AF burden assessed by PPM. There was no significant difference in AF burden on treatment with XEN-D0103 versus placebo. There was a reduction in the mean frequency of AF episodes (relative reduction 0.72, 95% CI 0.66 to 0.77; p < 0.0001). XEN-D0103 was safe and well tolerated, and there were no serious adverse events. XEN-D0103 did not have any apparent effect on heart rate compared to placebo.</AbstractText>XEN-D0103 did not reduce AF burden in patients with PAF and dual chamber pacemakers providing beat-to-beat monitoring. XEN-D0103 was well tolerated and did not have any apparent effect on heart rate. Although single-ion channel blockade with XEN-D0103 did not affect AF in this study, there might be a potential for this agent to be used in combination with other atrially specific drugs in the treatment of AF.</AbstractText>2013-004456-38.</AbstractText> |
19,629 | Structural heterogeneity of the rat pulmonary vein myocardium: consequences on intracellular calcium dynamics and arrhythmogenic potential. | Mechanisms underlying ectopic activity in the pulmonary vein (PV) which triggers paroxysmal atrial fibrillation are unknown. Although several studies have suggested that calcium signalling might be involved in these arrhythmias, little is known about calcium cycling in PV cardiomyocytes (CM). We found that individual PV CM showed a wide range of transverse tubular incidence and organization, going from their virtual absence, as described in atrial CM, to well transversally organised tubular systems, like in ventricular CM. These different types of CM were found in groups scattered throughout the tissue. The variability of the tubular system was associated with cell to cell heterogeneity of calcium channel (Ca<sub>v</sub>1.2) localisation and, thereby, of Ca<sub>v</sub>1.2-Ryanodine receptor coupling. This was responsible for multiple forms of PV CM calcium transient. Spontaneous calcium sparks and waves were not only more abundant in PV CM than in LA CM but also associated with a higher depolarising current. In conclusion, compared with either the atrium or the ventricle, PV myocardium presents marked structural and functional heterogeneity. |
19,630 | Clinical and Angiographic Predictors of Mortality in Sudden Cardiac Arrest Patients Having Cardiac Catheterisation: A Single Centre Registry. | Immediate cardiac catheterisation (CC) is recommended in ST-elevation myocardial infarction (STEMI) following sudden cardiac arrest (SCA). Guidelines advise urgent CC for SCA patients without-STEMI, at clinician discretion. We examined the clinical and angiographic factors predicting mortality in SCA patients having CC.</AbstractText>Consecutive SCA patients having CC at Liverpool Hospital, Sydney (January 2011-September 2015) were retrospectively analysed. Patient data were retrieved from hospital records, and angiographic SYNTAX scores (SS) were quantified online. Independent predictors of mortality were derived using multivariate logistic analysis.</AbstractText>The study cohort comprised 104 SCA patients; mean age 61±12years, and 79% male. Immediate CC (<2hours post-SCA) was performed in 35% overall. Compared to the without-STEMI subgroup, STEMI patients had more ventricular fibrillation (91 vs 50%; p<0.0001), and higher mean peak serum high-sensitivity troponin-T (8.25±14.7 vs 1.97±6.13 ug/L; p=0.006); in the context of higher median SS (18 vs 6.5; p=0.002) and target-lesion SS (tSS, 10 vs 0; p<0.001). Percutaneous coronary intervention (PCI; 75 vs 23%; p<0.0001) and target vessel revascularisation (11 vs 0%; p=0.005) were more frequent for STEMI. All-cause mortality was 39%, at 1.3±1.5years follow-up. Independent mortality predictors were: delayed CC (HR 4.08), serum lactate >7mmol/L (HR 3.47), and tSS (HR 1.05).</AbstractText>Elevated serum lactate, tSS, and delayed CC, were predictive of longer-term mortality in SCA patients having CC. Late CC in patients without-STEMI suggest scope for improvement in real-world systems of care. Closer scrutiny of target lesion complexity may aid prognostication in SCA survivors.</AbstractText>Copyright © 2018. Published by Elsevier B.V.</CopyrightInformation> |
19,631 | Comparison of left atrial size and function in hypertrophic cardiomyopathy and in Fabry disease with left ventricular hypertrophy. | Fabry disease (FD) and hypertrophic cardiomyopathy (HCM) are two diseases with a different pathophysiology, both cause left ventricular hypertrophy (LVH) and myocardial fibrosis. Although remodeling and systolic dysfunction of the left atrium (LA) are associated with atrial fibrillation and stroke in HCM, changes in the size and function of the LA have not been well studied in FD with LVH.</AbstractText>The following groups were studied prospectively, and their respective findings compared: 19 patients with non-obstructive HCM (Group I), 20 patients with a diagnosis of Fabry cardiomyopathy (Group II), and 20 normal subjects matched for sex and age (Group III). Left ventricular mass index was measured using Devereux' formula, left atrial volume with Simpson's biplane method and left atrial mechanical function, including strain and strain rate, was measured using the speckle tracking technique. Strain and strain rate of the reservoir were measured during the three phases: reservoir (SR S), passive conduit (SR E) and atrial contraction (SR A).</AbstractText>Patients with HCM had a larger left atrial volume than patients with FD (48.16 ± 14.3 mL/m2</sup> vs 38.9 ± 14.9 mL/m2</sup> respectively, P < .001), but in both disorders there was a severe decrease in left atrial function: reservoir strain in the apical four-chamber view: 17.47% in HCM vs 22.5% in FD, P = .24), strain rate in the apical chamber view: SR A: -0.80/seconds in HCM vs -1.04/seconds in FD (P = .88), SR S: 0.69/seconds in HCM vs 0.93 in FD (P = .12), SR E: -0.80 seconds in HCM vs -0.97/seconds in FD (P = .18).</AbstractText>In this echocardiographic study we used speckle tracking to assess left atrial mechanical function and showed that FD is associated to an atrial cardiomyopathy, affecting the three phasic functions of the LA. Although in patients with HCM left atrial volume is larger than in patients with FD, both disorders exhibit severe decrease in left atrial function. These findings should be considered, given the potentially serious complications that can occur with the two diseases.</AbstractText>© 2018 Wiley Periodicals, Inc.</CopyrightInformation> |
19,632 | Unexpected bioprosthetic mitral valve thrombus during left ventricular assist device implantation. | Acute bioprosthetic valve thrombosis can occur after surgery and sometimes cause hemodynamic instability and cardiogenic shock. Risk factors for bioprosthetic valve thrombosis are hypercoagulability, atrial fibrillation, atrial dilatation, low cardiac function, and lack of anticoagulation therapy. The authors present a case of severe mitral stenosis due to bioprosthetic valve thrombus. The patient was diagnosed with dilated-phase hypertrophic cardiomyopathy and underwent mitral valve replacement. He required venoarterial extracorporeal membrane oxygenation (VA-ECMO) due to extremely low cardiac output and was scheduled for left ventricular assist device (LVAD) implantation. Transesophageal echocardiographic examination before LVAD implantation revealed severe mitral stenosis due to bioprosthetic mitral valve thrombus, which was not detected by transthoracic echocardiography in the intensive care unit and contributed to the low cardiac function. The thrombus was removed through an unscheduled left atriotomy before LVAD implantation. The possibility of bioprosthetic valve thrombosis must be considered when the patient is dependent on VA-ECMO support. Early transesophageal echocardiographic examination of the bioprosthetic valve may be helpful and contribute to surgical decision-making. |
19,633 | Sudden cardiac arrest in hypertrophic cardiomyopathy with dynamic cavity obstruction: The case for a decatecholaminisation strategy. | Catecholamines are entrenched in the management of shock states. A paradigm shift has pervaded the critical care arena in recent years acknowledging their propensity to cause harm and fuel a 'death-spiral'. We present the case of a 21-year-old male following a witnessed out-of-hospital cardiac arrest who received high-quality cardiopulmonary resuscitation and standard advanced life support for refractory ventricular fibrillation until return of spontaneous circulation after 70 min. Early post-admission echocardiography revealed severe diffuse sub-basal left ventricular hypertrophy with dynamic mid-cavity obstruction and akinetic apical pouching. Within this context, a decatecholaminised strategy comprising a beta-blocker was used to augment the left ventricular end-diastolic volume and attain cardiovascular stability. |
19,634 | Thoracoscopic Sympathectomy for Refractory Electrical Storm After Coronary Artery Bypass Grafting. | We report a patient with refractory electrical storm after coronary artery bypass grafting who was successfully treated with thoracoscopic sympathectomy. Cardiac arrest with ventricular tachycardia occurred on postoperative day 2, and the patient required emergency support with venoarterial extracorporeal membrane oxygenation. Frequent episodes of ventricular tachycardia prevented cardiac recovery and weaning from mechanical circulatory support. A percutaneous left stellate ganglion block initially demonstrated successful prevention of ventricular tachycardia, and definitive sympathetic denervation was achieved by a left thoracoscopic sympathectomy. The patient remained in normal sinus rhythm and gained recovery of baseline ventricular function, permitting successful decannulation and weaning of inotropic support. |
19,635 | Right atrium enlargement predicts clinically significant supraventricular arrhythmia in patients with pulmonary arterial hypertension. | Right atrial (RA) enlargement is a common finding in patients with pulmonary arterial hypertension (PAH) and an important predictor of mortality, however its relation to the risk of atrial arrhythmias has not been assessed.</AbstractText>To assess whether RA enlargement is associated with supraventricular arrhythmias (SVA) and whether it predicts new clinically significant SVA (csSVA).</AbstractText>Patients with PAH were recruited between January 2010 and December 2014 and followed until January 2017. csSVA was diagnosed if it resulted in hospitalization. To assess predictors of new csSVA, only patients without a history of SVA at baseline were analyzed.</AbstractText>Among 97 patients, any SVA was observed in 45 (46.4%) and included permanent atrial fibrillation(AF, n = 8), paroxysmal AF (n = 10), permanent atrial flutter (AFl, n = 1), paroxysmal AFl (n = 2) or other types of supraventricular tachycardia (n = 24). Patients with SVA as compared to patients without SVA were characterized by older age, lower distance in a 6-minute test, higher NT-proBNP, higher RA area index (RAai), left atrial area index, mean right atrial pressure (mRAP) and were more commonly treated with β-blocker. Eighty five patients who were in sinus rhythm at baseline assessment and had no history of significant SVA were observed for 37 ± 19.9 months. During that time csSVA occurred in 15.3%. In univariate models, the occurrence of csSVA were predicted by age, right ventricular ejection fraction, right ventricular end diastolic index, RAai and mRAP, but in multivariate model only RAai remained significant predictor for csSVA (HR of 1.23, 95%CI: 1.11-1.36, p < 0.001). The optimal threshold for RA enlargement as discriminator of csSVA was 21.7 cm2/m2.</AbstractText>In PAH patients RA enlargement is associated with increased prevalence of SVA. RAai is an independent predictor of hospitalization due to csSVA.</AbstractText>Copyright © 2018 Elsevier Inc. All rights reserved.</CopyrightInformation> |
19,636 | Technology Advances to Improve Response to Cardiac Resynchronization Therapy: What Clinicians Should Know. | Cardiac resynchronization therapy (CRT) is a well-established treatment for symptomatic heart failure patients with reduced left ventricular ejection fraction, prolonged QRS duration, and abnormal QRS morphology. The ultimate goals of modern CRT are to improve the proportion of patients responding to CRT and to maximize the response to CRT in patients who do respond. While the rate of CRT nonresponders has moderately but progressively decreased over the last 20 years, mostly in patients with left bundle branch block, in patients without left bundle branch block the response rate is almost unchanged. A number of technological advances have already contributed to achieve some of the objectives of modern CRT. They include novel lead design (the left ventricular quadripolar lead, and multipoint pacing), or the possibility to go beyond conventional delivery of CRT (left ventricular endocardial pacing, His bundle pacing). Furthermore, to improve CRT response, a triad of actions is paramount: reducing the burden of atrial fibrillation, reducing the number of appropriate and inappropriate interventions, and adequately predicting heart failure episodes. As in other fields of cardiology, technology and innovations for CRT delivery have been at the forefront in transforming-improving-patient care; therefore, these innovations are discussed in this review. |
19,637 | Usefulness of Integrating Heart Failure Risk Factors Into Impairment of Global Longitudinal Strain to Predict Anthracycline-Related Cardiac Dysfunction. | The prediction of cancer therapeutics-related cardiac dysfunction (CTRCD) is an essential aspect of care for individuals who receive potentially cardiotoxic oncologic treatments. Certain clinical risk factors have been described for incident CTRCD, and measurement of left ventricular (LV) longitudinal strain by speckle tracking 2-dimensional echocardiography (2DE) is the best-validated myocardial mechanical imaging assessment to detect subtle changes in LV function during cancer treatment. However, the direct integration of clinical and imaging risk factors to predict CTRCD has not yet been extensively examined. This was a retrospective study of 183 women with breast cancer aged 50.9 ± 10.8 years who received treatment with anthracyclines (doxorubicin dose of 422 ± 69 mg/m<sup>2</sup>, with 41.2% of subjects also receiving trastuzumab) and underwent 2DE at clinically determined intervals. CTRCD was diagnosed when LV ejection fraction dropped ≥10% to a subnormal (<53%) value by 2DE. Left ventricular global longitudinal strain (LV-GLS) was assessed offline. The risk prediction tool based only on clinical factors previously described by Ezaz et al was applied to our cohort and accurately stratified these subjects into low-, intermediate-, and high-risk groups, with incident CTRCD in 7.4%, 26.9%, and 54.6%, respectively (chi-square = 20.7, p <0.0001). We developed novel multivariate models to predict CTRCD using (1) demographic variables only (c = 0.8674), (2) echocardiographic (peak LV-GLS) variables only (c = 0.8440), or (3) a combination of demographic and echocardiographic variables, with the combined model exhibiting superior receiver-operating characteristics (c = 0.9629). In conclusion, estimation of CTRCD risk should integrate all available data, including both clinical variables and an imaging assessment. |
19,638 | Prognostic implications of early monomorphic and non-monomorphic tachyarrhythmias in patients discharged with acute coronary syndrome. | The prognostic implication of early ventricular tachyarrhythmias (VTs) after acute coronary syndrome (ACS) remains unclear.</AbstractText>We sought to investigate the clinical outcomes of early monomorphic and non-monomorphic VTs that occur within 48 hours in patients after ACS.</AbstractText>We retrospectively reviewed the clinical outcomes of 2033 [mean age 67.0 ± 13.4 years; 1486 (73.1%) men] consecutive patients who presented with ACS from 2004 to 2015.</AbstractText>A total of 67 (3.3%) and 90 (4.4%) patients developed early monomorphic or non-monomorphic VT, respectively. Killip class IV (odds ratio [OR] 3.05; 95% confidence interval [CI] 1.47-6.36; P < .01), creatine kinase level (OR 1.01; 95% CI 1.00-1.02 per 100 IU/L; P = .01), and left ventricular ejection fraction (OR 0.96; 95% CI 0.94-0.99; P < .01) were independently associated with early monomorphic VT, whereas age (OR 0.98; 95% CI 0.97-0.99; P = .04), ST elevated myocardial infarction (OR 3.53; 95% CI 1.71-7.27; P < .01), Killip class IV (OR 4.91; 95% CI 2.76-8.74; P < .01), diabetes mellitus (OR 0.48; 95% CI 0.28-0.81; P < .01), and left ventricular ejection fraction (OR 0.97; 95% CI 0.95-0.99; P < .01) were independently associated with early non-monomorphic VT. More patients with early monomorphic VT (n = 22 [32.8%]) died in hospital than those with non-monomorphic VT (n = 16 [17.8%]) or without early VT (n = 133 [7.1%]; P < .01). After a mean follow-up of 67.8 ± 43.2 months, 21 patients with early monomorphic VT (46.7%), 22 patients with early non-monomorphic VT (29.7%), and 552 patients without early VT (31.7%) died. Both early monomorphic and non-monomorphic VTs were associated with a long-term increase in sudden arrhythmic deaths and recurrent VTs. Nevertheless, only early monomorphic VT was shown to independently predict overall survival (hazard ratio 1.62; 95% CI 1.03-2.55; P = .04).</AbstractText>Early monomorphic VT, but not early non-monomorphic VT, independently predicted all-cause mortality in patients with ACS who survived to hospital discharge.</AbstractText>Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
19,639 | Mechanisms and management of refractory ventricular arrhythmias in the age of autonomic modulation. | Ventricular arrhythmias are responsible for hundreds of thousands of deaths every year. Catheter ablation of ventricular tachycardia (VT) is an essential component of the management of these life-threatening arrhythmias. However, in many patients, despite medical and interventional therapy, VT recurs. Furthermore, some VT substrates (mid-myocardial, left ventricular summit, and intraseptal) are not easily targeted because of limitations of currently available technology. In certain clinical settings, ventricular fibrillation (VF) episodes that have premature ventricular contraction triggers can also be targeted with catheter ablation. However, in most patients there is no clear VF trigger to target, and therefore polymorphic VT or VF cannot be adequately treated with catheter ablation. The autonomic nervous system plays a crucial role in all aspects of ventricular arrhythmias, yet interventions specific to the cardiac neuronal axis have been largely underutilized. This underutilization has been most pronounced in patients with structural heart disease. However, there is a growing body of literature on the physiology and pathophysiology of cardiac neural control and the benefits of neuromodulation to treat refractory ventricular arrhythmias in these patients. We present case-based examples of neuromodulatory interventions currently available and a review of the literature supporting their use. |
19,640 | Vidarabine, an anti-herpesvirus agent, prevents catecholamine-induced arrhythmias without adverse effect on heart function in mice. | Sympathetic activation causes clinically important arrhythmias including atrial fibrillation (AF) and ventricular tachyarrhythmia. Although the usefulness of β-adrenergic receptor blockade therapy is widely accepted, its multiple critical side effects often prevent its initiation or continuation. The aim of this study is to determine the advantages of vidarabine, an adenylyl cyclase (AC)-targeted anti-sympathetic agent, as an alternative treatment for arrhythmia. We found that vidarabine, which we identified as a cardiac AC inhibitor, consistently shortens AF duration and reduces the incidence of sympathetic activation-induced ventricular arrhythmias. In atrial and ventricular myocytes, vidarabine inhibits adrenergic receptor stimulation-induced RyR2 phosphorylation, sarcoplasmic reticulum (SR) Ca<sup>2+</sup> leakage, and spontaneous Ca<sup>2+</sup> release from SR, the last of which has been considered as a potential arrhythmogenic trigger. Moreover, vidarabine also inhibits sympathetic activation-induced reactive oxygen species (ROS) production in cardiac myocytes. The pivotal role of vidarabine's inhibitory effect on ROS production with regard to its anti-arrhythmic property has also been implied in animal studies. In addition, as expected, vidarabine exerts an inhibitory effect on AC function, which is more potent in the heart than elsewhere. Indexes of cardiac function including ejection fraction and heart rate were not affected by a dosage of vidarabine sufficient to exert an anti-arrhythmic effect. These findings suggest that vidarabine inhibits catecholamine-induced AF or ventricular arrhythmia without deteriorating cardiac function in mice. |
19,641 | Performance of the 2015 International Task Force Consensus Statement Risk Stratification Algorithm for Implantable Cardioverter-Defibrillator Placement in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy. | Ventricular arrhythmias are a feared complication of arrhythmogenic right ventricular dysplasia/cardiomyopathy. In 2015, an International Task Force Consensus Statement proposed a risk stratification algorithm for implantable cardioverter-defibrillator placement in arrhythmogenic right ventricular dysplasia/cardiomyopathy.</AbstractText>To evaluate performance of the algorithm, 365 arrhythmogenic right ventricular dysplasia/cardiomyopathy patients were classified as having a Class I, IIa, IIb, or III indication per the algorithm at baseline. Survival free from sustained ventricular arrhythmia (VT/VF) in follow-up was the primary outcome. Incidence of ventricular fibrillation/flutter cycle length <240 ms was also assessed. Two hundred twenty-four (61%) patients had a Class I implantable cardioverter-defibrillator indication; 80 (22%), Class IIa; 54 (15%), Class IIb; and 7 (2%), Class III. During a median 4.2 (interquartile range, 1.7-8.4)-year follow-up, 190 (52%) patients had VT/VF and 60 (16%) had ventricular fibrillation/flutter. Although the algorithm appropriately differentiated risk of VT/VF, incidence of VT/VF was underestimated (observed versus expected: 29.6 [95% confidence interval, 25.2-34.0] versus >10%/year Class I; 15.5 [confidence interval 11.1-21.6] versus 1% to 10%/year Class IIa). In addition, the algorithm did not differentiate survival free from ventricular fibrillation/flutter between Class I and IIa patients (P</i>=0.97) or for VT/VF in Class I and IIa primary prevention patients (P</i>=0.22). Adding Holter results (<1000 premature ventricular contractions/24 hours) to International Task Force Consensus classification differentiated risks.</AbstractText>While the algorithm differentiates arrhythmic risk well overall, it did not distinguish ventricular fibrillation/flutter risks of patients with Class I and IIa implantable cardioverter-defibrillator indications. Limited differentiation was seen for primary prevention cases. As these are vital uncertainties in clinical decision-making, refinements to the algorithm are suggested prior to implementation.</AbstractText>© 2018 American Heart Association, Inc.</CopyrightInformation> |
19,642 | Prognostic role of cardiac calcifications in primary prevention: A powerful marker of adverse outcome highly dependent on underlying cardiac rhythm. | Increasing evidence exists regarding calcium detected in aortic cusps and/or mitral annulus (AOC_MAC) at transthoracic echocardiogram as a predictor of cardiovascular (CV) events and mortality.</AbstractText>To verify whether AOC_MAC has a prognostic role in the setting of primary prevention independently of the presence of atrial fibrillation (AF).</AbstractText>All subjects consecutively referred from January 2011 to October 2014 to the Cardiovascular Centre for CV risk assessment in primary prevention were selected. AOC_MAC was assessed by transthoracic echocardiography. Primary study endpoint was a composite of CV hospitalizations/all-cause death.</AbstractText>The 1389 study patients were 70 years old, 43% males, 24% had diabetes mellitus, 75% arterial hypertension, 56% dyslipidaemia. Of all, 997 (72%) were in sinus rhythm (SR), 392 (28%) in AF. Patients with AF were older and more frequently males, with larger atria than SR subjects. During a median follow-up of 32 months, 165 patients (12%) were hospitalized for CV cause, 68 (5%) died. The primary endpoint occurred more frequently in patients with than without AOC_MAC (18% vs 11%, p < 0.001). AF patients showed higher event-rate compared with patients in SR (20% vs 10%, respectively; p < 0.01). AOC_MAC emerged as an independent prognosticator of primary endpoint in SR patients (HR 1.74 [1.07-2.82], p = 0.02), together with increasing age and left ventricular hypertrophy, while AOC_MAC had no prognostic relevance in AF patients.</AbstractText>In subjects with multiple CV risk factors assessed in primary prevention, the presence of AF nullifies the prognostic power of AOC_MAC, on the contrary robustly confirmed in SR patients.</AbstractText>Copyright © 2018 Elsevier B.V. All rights reserved.</CopyrightInformation> |
19,643 | The predictive role of E/e' on ischemic stroke and atrial fibrillation in Japanese patients without atrial fibrillation. | The predictive role of E/e' on ischemic stroke (IS) and atrial fibrillation (AF) in Japanese patients without AF are unclear.</AbstractText>Shinken database includes all the new patients visiting the Cardiovascular Institute Hospital in Tokyo, Japan. E/e' has been routinely measured since 2007. Patients without AF for whom E/e' was measured at the initial visit between 2007 and 2014 (n=11 477, mean age 57.2 years old, men 59.5%) were divided into E/e' tertiles (<8.04, 8.04-11.00, >11.00). During the mean follow-up period of 1.8 years, 58 IS and 140 new appearances of AF were observed. High E/e' tertile was associated with more prevalence of atherothrombotic risks. The cumulative incidence of IS events and new appearance of AF at 6 years in low, middle, and high E/e' tertiles were 0.5%, 1.4%, and 3.0%/year (log-rank test, p<0.001), and 2.5%, 2.9%, and 4.2%/year (log-rank test, p=0.007), respectively. In multivariate analysis, high E/e' tertile was independently associated with IS (HR, 2.857, 95%CI 1.257-6.495, p=0.012). Although high E/e' tertile was independently associated with new appearance of AF when adjusted for coexistence of atherothrombotic risk factors (HR, 1.694, 95%CI, 1.097-2.616, p=0.017), the association was attenuated after adjustment for left atrial dimension.</AbstractText>E/e' was significantly associated with incidence of IS and new appearance of AF in non-AF patients.</AbstractText>Copyright © 2018 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.</CopyrightInformation> |
19,644 | Prognostic Significance of Complex Ventricular Arrhythmias Complicating ST-Segment Elevation Myocardial Infarction. | The aim of the study was to assess the clinical significance of complex ventricular arrhythmias (VAs) (sustained ventricular tachycardia [sVT] and ventricular fibrillation [VF]) in patients with ST-segment elevation myocardial infarction (STEMI) depending on timing of arrhythmia. We analyzed 4,363 consecutive patients with STEMI treated invasively between 2004 and 2014. The median follow-up was 69.6 months (range: 0 to 139.8 months). The study population was divided into 2 main groups; VA group encompassed 476 patients (10.91%) with VAs, whereas 3,887 subjects (89.09%) without VT or VF were included into the control group. In VA population, prereperfusion VA (34.24%; n = 163) was the most common arrhythmia, whereas reperfusion-induced, early postreperfusion, and late postreperfusion VAs were diagnosed in 103 (21.64%), 103 (21.64%), and 107 (22.48%) patients, respectively. Every type of sVT or VF complicating STEMI portended significantly worse in-hospital prognosis, however a late onset arrhythmia was associated with the highest (over fivefold) and reperfusion-induced VA with the lowest (less than threefold) increase in mortality risk compared with the control group. On the contrary, long-term mortality was significantly increased only in subjects with late postreperfusion and prereperfusion VAs compared with VA-free population (43.93% and 36.81%, respectively vs 22.58%; p <0.001). Apart from cardiogenic shock on admission, late postreperfusion (hazard ratio 3.39) and prereperfusion VAs (hazard ratio 2.76) were the strongest independent predictors of death in the analyzed population. In conclusion, 1 in 10 patients with STEMI treated invasively was affected by sVT or VF. The clinical impact of VAs was strongly dependent on timing of arrhythmia. |
19,645 | Intrinsic changes of left ventricular function in patients with Behçet disease and comparison according to systemic disease activity. | Although cardiac manifestation of Behçet disease (BD) has been described in sporadic reports, its timely diagnosis remains difficult. The objective of this study was to describe early cardiac manifestations of BD. We also performed a comprehensive classification of systemic BD activity and compared their cardiac manifestations.</AbstractText>A prospective screening using speckle tracking echocardiography was performed in 85 patients with BD who had no history of heart disease. After excluding subjects with left ventricular (LV) ejection fraction (LVEF) <50% (n = 1), atrial fibrillation (n = 2), or inadequate echocardiographic images (n = 1), we analyzed their clinical and echocardiographic parameters including LV global longitudinal strains (GLS) and compared them with those of an age- and gender-matched control group (n = 145). Systemic BD activity was classified as minimal (Group A), controlled (Group B), and active (Group C).</AbstractText>In 81 study patients (59 females, age of 51 ± 11 years), echocardiography revealed a mean LVEF of 64 ± 5% without any significant valvular dysfunction or aortic aneurysm. Although there was no difference in LVEF between the control group and the patient group, the patient group showed significant reduction in GLS (-17.1 ± 2.9% vs -20.8 ± 2.2%, P < .001). Groups A (n = 21, 26%), B (n = 47, 58%), and C (n = 13, 58%) consistently showed reduction in GLS compared with the control group. However, there was no significant difference in cardiac manifestations among these groups according to systemic disease activity.</AbstractText>Patients with BD present intrinsic LV dysfunction despite no apparent abnormality on routine echocardiography. However, their cardiac manifestations are not proportional to systemic BD activity.</AbstractText>© 2018 Wiley Periodicals, Inc.</CopyrightInformation> |
19,646 | A clinical approach to arrhythmias revisited in 2018 : From ECG over noninvasive and invasive electrophysiology to advanced imaging. | Understanding arrhythmias and their treatment is not always easy. The current straightforward approach with catheter ablation and device therapy is an amazing achievement, but does not make management of underlying or other cardiac disease and pharmacological therapy unnecessary. The goal of this paper is to describe how much of the knowledge of the 1980s and early 1990s can and should still be applied in the modern treatment of patients with arrhythmias. After an introduction, this review will focus on paroxysmal atrial fibrillation and a prototype of 'idiopathic' ventricular arrhythmias, two diseases with a striking similarity, and will discuss the arrhythmogenesis. The ECG continues to play an important role in diagnostics. Both diseases are associated with a structurally normal heart; the autonomic nervous system plays an important role in triggering arrhythmias at both the atrial and ventricular level. |
19,647 | Irregularity and lack of p waves in short tachycardia episodes predict atrial fibrillation and ischemic stroke. | Atrial fibrillation (AF) is defined as an irregular supraventricular tachycardia (SVT) without p waves, with duration >30 seconds. Whether AF characteristics during short SVT episodes predict AF and stroke is not known.</AbstractText>The purpose of this study was to determine whether irregularity and lack of p waves, alone or in combination, during short SVT episodes increase the risk of incident AF and ischemic stroke.</AbstractText>The population-based Malmö Diet and Cancer study includes 24-hour ECG screening of 377 AF-free individuals (mean age 64.5 years; 43% men) who were prospectively followed for >13 years. There were 65 AF events and 25 ischemic stroke events during follow-up. Subjects with an SVT episode ≥5 beats were identified, and the longest SVT episode was assessed for irregularity and lack of p waves. The association between SVT classification and AF and stroke was assessed using multivariable adjusted Cox regression.</AbstractText>The incidence of AF increased with increasing abnormality of the SVTs. The risk-factor adjusted hazard ratio for AF was 4.95 (95% confidence interval 2.06-11.9; P <.0001) for those with short irregular SVTs (<70 beats) without p waves. The incidence of ischemic stroke was highest in the group with regular SVT episodes without p waves (hazard ratio 14.2; 95% confidence interval 3.76-57.6; P <.0001, adjusted for age and sex).</AbstractText>Characteristics of short SVT episodes detected at 24-hour ECG screening are associated with incident AF and ischemic stroke. Short irregular SVTs without p waves likely represent early stages of AF or atrial myopathy. Twenty-four-hour ECG could identify subjects suitable for primary prevention efforts.</AbstractText>Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
19,648 | New-Onset Atrial Fibrillation After PCI or CABG for Left Main Disease: The EXCEL Trial. | There is limited information on the incidence and prognostic impact of new-onset atrial fibrillation (NOAF) following percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) for left main coronary artery disease (LMCAD).</AbstractText>This study sought to determine the incidence of NOAF following PCI and CABG for LMCAD and its effect on 3-year cardiovascular outcomes.</AbstractText>In the EXCEL (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial, 1,905 patients with LMCAD and low or intermediate SYNTAX scores were randomized to PCI with everolimus-eluting stents versus CABG. Outcomes were analyzed according to the development of NOAF during the initial hospitalization following revascularization.</AbstractText>Among 1,812 patients without atrial fibrillation on presentation, NOAF developed at a mean of 2.7 ± 2.5 days after revascularization in 162 patients (8.9%), including 161 of 893 (18.0%) CABG-treated patients and 1 of 919 (0.1%) PCI-treated patients (p < 0.0001). Older age, greater body mass index, and reduced left ventricular ejection fraction were independent predictors of NOAF in patients undergoing CABG. Patients with versus without NOAF had a significantly longer duration of hospitalization, were more likely to be discharged on anticoagulant therapy, and had an increased 30-day rate of Thrombolysis In Myocardial Infarction major or minor bleeding (14.2% vs. 5.5%; p < 0.0001). By multivariable analysis, NOAF after CABG was an independent predictor of 3-year stroke (6.6% vs. 2.4%; adjusted hazard ratio [HR]: 4.19; 95% confidence interval [CI]: 1.74 to 10.11; p = 0.001), death (11.4% vs. 4.3%; adjusted HR: 3.02; 95% CI: 1.60 to 5.70; p = 0.0006), and the primary composite endpoint of death, MI, or stroke (22.6% vs. 12.8%; adjusted HR: 2.13; 95% CI: 1.39 to 3.25; p = 0.0004).</AbstractText>In patients with LMCAD undergoing revascularization in the EXCEL trial, NOAF was common after CABG but extremely rare after PCI. The development of NOAF was strongly associated with subsequent death and stroke in CABG-treated patients. Further studies are warranted to determine whether prophylactic strategies to prevent or treat atrial fibrillation may improve prognosis in patients with LMCAD who are undergoing CABG. (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization [EXCEL]; NCT01205776).</AbstractText>Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
19,649 | Stroke Risk in Patients With Reduced Ejection Fraction After Myocardial Infarction Without Atrial Fibrillation. | Stroke can occur after myocardial infarction (MI) in the absence of atrial fibrillation (AF).</AbstractText>This study sought to identify risk factors (excluding AF) for the occurrence of stroke and to develop a calibrated and validated stroke risk score in patients with MI and heart failure (HF) and/or systolic dysfunction.</AbstractText>The datasets included in this pooling initiative were derived from 4 trials: CAPRICORN (Effect of Carvedilol on Outcome After Myocardial Infarction in Patients With Left Ventricular Dysfunction), OPTIMAAL (Optimal Trial in Myocardial Infarction With Angiotensin II Antagonist Losartan), VALIANT (Valsartan in Acute Myocardial Infarction Trial), and EPHESUS (Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study); EPHESUS was used for external validation. A total of 22,904 patients without AF or oral anticoagulation were included in this analysis. The primary outcome was stroke, and death was treated as a "competing risk."</AbstractText>During a median follow-up of 1.9 years (interquartile range: 1.3 to 2.7 years), 660 (2.9%) patients had a stroke. These patients were older, more often female, smokers, and hypertensive; they had a higher Killip class; a lower estimated glomerular filtration rate; and a higher proportion of MI, HF, diabetes, and stroke histories. The final stroke risk model retained older age, Killip class 3 or 4, estimated glomerular filtration rate ≤45 ml/min/1.73 m2</sup>, hypertension history, and previous stroke. The models were well calibrated and showed moderate to good discrimination (C-index = 0.67). The observed 3-year event rates increased steeply for each sextile of the stroke risk score (1.8%, 2.9%, 4.1%, 5.6%, 8.3%, and 10.9%, respectively) and were in agreement with the expected event rates.</AbstractText>Readily accessible risk factors associated with the occurrence of stroke were identified and incorporated in an easy-to-use risk score. This score may help in the identification of patients with MI and HF and a high risk for stroke despite their not presenting with AF.</AbstractText>Copyright © 2018 American College of Cardiology Foundation. All rights reserved.</CopyrightInformation> |
19,650 | Surgical placement of a wireless telemetry device for cardiovascular studies of bovine calves. | <i>Background:</i> Domestic cattle ( <i>Bos taurus</i>) are naturally susceptible to hypoxia-induced pulmonary arterial hypertension; consequently, the bovine calf has been used with considerable success as an animal model of the analogous human condition. Studies to date, however, have relied on instantaneous measurements of pressure and cardiac output. Here, we describe the surgical technique for placement of a fully implantable wireless biotelemetry device in a bovine calf for measurement of pulmonary arterial and left ventricular pressures, right ventricular output, and electrocardiogram. <i>Methods:</i> Three, 2-month old bovine calves underwent left-sided thoracotomies. A transit-time flow probe was placed around the pulmonary artery and solid-state pressure catheters inserted into the pulmonary artery and left ventricle. Biopotential leads were secured to the epicardium. The implant body was secured subcutaneously, dorso-caudal to the incision. <i>Results:</i> The implant and sensors were successfully placed in two of the three calves. One calf died from ventricular fibrillation following left ventricular puncture prior to pressure sensor insertion. Anatomical discrepancies meant that either 4 <sup>th</sup> or 5 <sup>th</sup> rib was removed. The calves recovered quickly with minimal complications that included moderate dyspnea and subcutaneous edema. <i>Conclusions:</i> Left thoracotomy is a viable surgical approach for wireless biotelemetry studies of bovine calf cardiovascular function. The real-time, contemporaneous collection of cardiovascular pressures and output, permits pathophysiological studies in a naturally susceptible, large animal model of pulmonary arterial hypertension. |
19,651 | Chronic intermittent hypoxia promotes myocardial ischemia-related ventricular arrhythmias and sudden cardiac death. | We investigated the effects of intermittent hypoxia (IH), such as that encountered in severe obstructive sleep apnea (OSA) patients, on the development and severity of myocardial ischemia-related ventricular arrhythmias. Rats were exposed to 14 days of IH (30 s at 5%O<sub>2</sub> and 30 s at 21%O<sub>2</sub>, 8 h·day<sup>-1</sup>) or normoxia (N, similar air-air cycles) and submitted to a 30-min coronary ligature. Arterial blood pressure (BP) and ECG were recorded for power spectral analysis, ECG interval measurement and arrhythmia quantification. Left ventricular monophasic action potential duration (APD) and expression of L-type calcium (LTCC) and transient receptor potential (TRPC) channels were assessed in adjacent epicardial and endocardial sites. Chronic IH enhanced the incidence of ischemic arrhythmias, in particular ventricular fibrillation (66.7% vs. 33.3% in N rats, p < 0.05). IH also increased BP and plasma norepinephine levels along with increased low-frequency (LF), decreased high-frequency (HF) and increased LF/HF ratio of heart rate and BP variability. IH prolonged QTc and Tpeak-to-Tend intervals, increased the ventricular APD gradient and upregulated endocardial but not epicardial LTCC, TRPC1 and TRPC6 (p < 0.05). Chronic IH, is a major risk factor for sudden cardiac death upon myocardial ischemia through sympathoactivation and alterations in ventricular repolarization, transmural APD gradient and endocardial calcium channel expression. |
19,652 | Utility of Fluid Assessment Based on the Intrathoracic Impedance Monitoring in a Peripartum Woman with Heart Disease. | Recently, implantable cardioverter-defibrillators (ICD) have become capable of monitoring intrathoracic impedance to detect an increased fluid volume and heart failure. Pregnancy is a well-known cause of an increased body fluid volume; however, it is not clear whether the measurement of intrathoracic impedance by ICD is clinically useful for precisely detecting heart failure in pregnant women. We herein report the case of a 39-year-old woman with an ICD that had been implanted after an event of ventricular fibrillation due to severe aortic regurgitation with a bicuspid aortic valve. Elevated right ventricular pressure and brain natriuretic peptide levels were detected at 37 weeks of gestation and postpartum. At the same time, the ICD's stored fluid index gradually increased and exceeded the threshold on the 10th day after delivery. She was treated with diuretics and recovered from postpartum heart failure. The physiological volume changed in the perinatal period, but we were still able to detect heart failure by ICD. Intrathoracic impedance monitoring is effective in the perinatal field. |
19,653 | An Inappropriate Shock Case Early after Implantation of a Subcutaneous Cardiac Defibrillator by Subcutaneous Entrapped Air. | A 17-year-old woman was resuscitated from cardiac arrest due to ventricular fibrillation and was diagnosed with concealed long QT syndrome. She underwent subcutaneous implantable cardiac defibrillator (S-ICD) implantation at our hospital. The device electrogram immediately after implantation was normal. Four days after implantation, she received an inappropriate shock. The device interrogation revealed a continuous baseline shift and frequent oversensing for low amplitude signals, followed by a shock. A chest radiograph in the orthogonal view showed entrapped subcutaneous air surrounding the distal electrode. Entrapped subcutaneous air can cause inappropriate shocks in the early period after S-ICD implantation. |
19,654 | Can Gasping be Used as a Tool to Determine Whether to Perform Compression-Only CPR versus Conventional CPR? | Rottenberg EM . Can gasping be used as a tool to determine whether to perform compression-only CPR versus conventional CPR? Prehosp Disaster Med. 2018;33(2):225-226. |
19,655 | Risk Stratification of Sudden Cardiac Death After Acute Myocardial Infarction. | Despite advances in the diagnosis and treatment of acute coronary syndromes and an overall improvement in outcomes, mortality after myocardial infarction (MI) remains high. Sudden death, which is most frequently due to ventricular tachycardia or ventricular fibrillation, is the cause of death in 25% to 50% of patients with prior MI, and therefore represents an important public health problem. Use of the implantable cardioverter-defibrillator (ICD), which is the primary method of reducing the chance of arrhythmic sudden death after MI, is costly to the medical system and is associated with procedural and long-term risks. Additionally, assessment of left ventricular ejection fraction (LVEF), which is the primary method of assessing a patient's post-MI sudden death risk and appropriateness for ICD implantation, lacks both sensitivity and specificity for sudden death, and may not be the optimal way to select the subgroup of post-MI patients who are most likely to benefit from ICD implantation. To optimally utilize ICDs, it is therefore critical to develop and prospectively validate sudden death risk stratification methods beyond measuring LVEF. A variety of tests that assess left ventricular systolic function/morphology, potential triggers for ventricular arrhythmias, ventricular conduction/repolarization, and autonomic tone have been proposed as sudden death risk stratification tools. Multivariable models have also been developed to assess the competing risks of arrhythmic and non-arrhythmic death so that ICDs can be utilized more effectively. This manuscript will review the epidemiology of sudden death after MI, and will discuss the current state of sudden death risk stratification in this population. |
19,656 | Atrial Fibrillation and Ventricular Tachycardia in a Patient with Cardiac Sarcoidosis. | Cardiac sarcoidosis (CS) can cause atrial and ventricular arrhythmias, conduction system disease, and congestive heart failure. The use of advanced imaging modalities including cardiac magnetic resonance and positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose can be helpful in evaluating the extent of disease and response to treatment. The management of CS patients can be challenging, requiring immunosuppression medications, antiarrhythmic drugs, implantable cardiac devices, and cardiac ablation procedures. We report a patient with CS initially presenting with paroxysmal atrial fibrillation who later developed polymorphic ventricular tachycardia, highlighting the complexity of diagnosis and management in patients with multisystem sarcoidosis. |
19,657 | The Complexity of Pediatric Multifocal Atrial Tachycardia and Its Prognostic Factors. | Multifocal atrial tachycardia (MAT), in general, has a favorable outcome. However, there are insufficient data regarding MAT in a pediatric population. This study sought to determine the clinical course of MAT and identify potential prognostic factors.</AbstractText>The medical records of MAT patients from 1997-2015 were reviewed. The arrhythmia control rate and factors for unfavorable outcomes were assessed and compared to those in the literature.</AbstractText>Of the 33 included patients (19 boys and 14 girls), 27 were infants less than 1 year of age. The median age at diagnosis was 1.7 months (range, 0 day to 14 years). Fourteen (42%) patients had structural heart disease. Eight (24%) patients had lung disease and 6 (18%) had a syndromic diagnosis belonging to RASopathy. Two patients developed polymorphic ventricular tachycardia, in whom genetic analysis confirmed the presence of the RyR2 mutation several years later. MAT was controlled in 26 patients (84%) within 3.9 months (median; range, 16 days-18.4 years) using an average of 2.4 medications. There were 3 cases of cardiopulmonary mortality. The arrhythmia control rate was higher in the infant group (85%) than in the non-infant group (67%), although this trend was not statistically significant. There was a significantly lower rate of unfavorable outcomes in the idiopathic infant group (n=11) than in the other groups (p=0.008). Considering the findings of previous studies, the mortality rate was significantly higher in patients with structural heart disease than in patients without (21% vs. 5%, p=0.01).</AbstractText>MAT usually affects infants and has a favorable prognosis, particularly in the idiopathic infant group. However, in the presence of other comorbidities, MAT may have a variable clinical course.</AbstractText>Copyright © 2018. The Korean Society of Cardiology</CopyrightInformation> |
19,658 | Cardiovascular safety of prokinetic agents: A focus on drug-induced arrhythmias. | Gastrointestinal sensorimotor dysfunction underlies a wide range of esophageal, gastric, and intestinal motility and functional disorders that collectively constitute nearly half of all referrals to gastroenterologists. As a result, substantial effort has been dedicated toward the development of prokinetic agents intended to augment or restore normal gastrointestinal motility. However, the use of several clinically efficacious gastroprokinetic agents, such as cisapride, domperidone, erythromycin, and tegaserod, is associated with unfavorable cardiovascular safety profiles, leading to restrictions in their use.</AbstractText>The purpose of this review is to detail the cellular and molecular mechanisms that lead commonly to drug-induced cardiac arrhythmias, specifically drug-induced long QT syndrome, torsades de pointes, and ventricular fibrillation, to examine the cardiovascular safety profiles of several classes of prokinetic agents currently in clinical use, and to explore potential strategies by which the risk of drug-induced cardiac arrhythmia associated with prokinetic agents and other QT interval prolonging medications can be mitigated successfully.</AbstractText>© 2018 John Wiley & Sons Ltd.</CopyrightInformation> |
19,659 | RHYTHM: An Open Source Imaging Toolkit for Cardiac Panoramic Optical Mapping. | Fluorescence optical imaging techniques have revolutionized the field of cardiac electrophysiology and advanced our understanding of complex electrical activities such as arrhythmias. However, traditional monocular optical mapping systems, despite having high spatial resolution, are restricted to a two-dimensional (2D) field of view. Consequently, tracking complex three-dimensional (3D) electrical waves such as during ventricular fibrillation is challenging as the waves rapidly move in and out of the field of view. This problem has been solved by panoramic imaging which uses multiple cameras to measure the electrical activity from the entire epicardial surface. However, the diverse engineering skill set and substantial resource cost required to design and implement this solution have made it largely inaccessible to the biomedical research community at large. To address this barrier to entry, we present an open source toolkit for building panoramic optical mapping systems which includes the 3D printing of perfusion and imaging hardware, as well as software for data processing and analysis. In this paper, we describe the toolkit and demonstrate it on different mammalian hearts: mouse, rat, and rabbit. |
19,660 | Cough as the sole manifestation of pericardial effusion. | A 59-year-old woman with paroxysmal atrial fibrillation (AF) presented with severe non-productive cough, malaise, low-grade fever and AF flare-up 3 weeks following pulmonary vein isolation with radiofrequency catheter ablation. She denied chest pain or dyspnoea. Patient was haemodynamically stable. There was no pulsus paradoxus. Laboratories showed leucocytosis and elevated C-reactive protein. ECG showed sinus tachycardia. CT abdomen and pelvis showed a large pericardial effusion (PE). Shortly after admission, she developed AF with rapid ventricular response, responsive to intravenous amiodarone. Transthoracic echocardiogram revealed 2.4 cm posterior PE without tamponade physiology, non-amenable to pericardiocentesis via sub-xiphoid approach. Patient underwent left thoracoscopic pericardial window with removal of 250 cc bloody fibrinous fluid. Cough improved significantly and she was discharged on oral amiodarone and apixaban. Repeat CT chest after 2 weeks for recurrent cough showed a small PE, treated with oral prednisone for suspected postablation pericarditis, with complete resolution of cough. Amiodarone was stopped without recurrence of AF. |
19,661 | Significance of Coronary Artery Spasm Diagnosis in Patients With Early Repolarization Syndrome. | Previously described patients with early repolarization syndrome (ERS) may have experienced silent coronary artery spasm (CAS) because the diagnosis of CAS was mainly based on symptoms or coronary angiography findings, without performing a spasm provocation test. This study investigated the significance of CAS diagnosis and evaluated the incidence of silent CAS in patients with possible ERS (ie, idiopathic ventricular fibrillation [VF] and inferolateral J wave).</AbstractText>The study included 34 patients with idiopathic VF and inferolateral J wave. Thirteen patients (38%) were diagnosed as having CAS on the basis of coronary angiography with spasm provocation test (n=8) and documentation of spontaneous ST elevation (n=5). Of the 13 patients with CAS, 5 (38%) did not experience chest symptoms before and during VF, and were diagnosed as having silent CAS. The remaining 21 patients (62%), with a negative provocation test result and absence of chest symptoms, were considered to have ERS. During the 92 months of follow-up, patients with CAS receiving appropriate medical treatment with antianginal drugs showed a favorable outcome. In contrast, 4 of 21 patients with ERS (19%) had VF recurrences. The use of monotherapy or combination therapy, consisting of quinidine, cilostazol, and bepridil, in the 4 patients with ERS, was effective in suppressing VF.</AbstractText>Approximately 40% of patients with CAS with documented VF and inferolateral J wave did not experience chest symptoms at the first VF, and could have been misdiagnosed as having ERS. The use of the spasm provocation test is considered essential to differentiate patients for optimal medical treatment.</AbstractText>© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.</CopyrightInformation> |
19,662 | Effects of preconditioned plasma collected during the late phase of remote ischaemic preconditioning on ventricular arrhythmias caused by myocardial ischaemia reperfusion in rats. | Objective The administration of preconditioned plasma collected during the late phase of preconditioning has been shown to reduce myocardial infarct size. This study aimed to investigate if preconditioned plasma could attenuate ventricular arrhythmias in a rat model in vivo. Methods Eighty rats were randomized to eight groups (10 rats/group). Two groups provided preconditioned or non-preconditioned plasma 48 h after transient limb ischaemia or the control protocol. Six groups of ischaemia-reperfusion (IR) rats received normal saline, non-preconditioned plasma, or preconditioned plasma, respectively, 1 h (groups A1, A2, A3) or 24 h (groups B1, B2, B3) before undergoing myocardial IR. Electrocardiograms were monitored using a BIOPAC system, and the incidence and duration of ventricular tachycardia (VT) and ventricular fibrillation (VF) were analysed. Results No significant differences existed in the incidence and duration of VT or VF among groups A1-A3 or in the incidence and duration of VT among groups B1-B3. However, there was a significantly lower incidence and shorter duration of VF in group B3 rats than in group B1 rats. Conclusion Preconditioned plasma collected during the late phase of preconditioning can reduce the incidence and duration of VF compared with normal saline, suggesting its anti-arrhythmic potential. |
19,663 | A pharmacokinetic model for amiodarone in infants developed from an opportunistic sampling trial and published literature data. | Amiodarone is a first-line antiarrhythmic for life-threatening ventricular fibrillation or ventricular tachycardia in children, yet little is known about its pharmacokinetics (PK) in this population. We developed a population PK (PopPK) model using samples collected via an opportunistic study design of children receiving amiodarone per standard of care supplemented by amiodarone PK data from the literature. Both study data and literature data were predominantly from infants < 2 years old, so our analysis was restricted to this group. The final combined dataset consisted of 266 plasma drug concentrations in 45 subjects with a median (interquartile range) postnatal age of 40.1 (11.0-120.4) days and weight of 3.9 (3.1-5.1) kg. Since the median sampling time after the first dose was short (study: 95 h; literature: 72 h) relative to the terminal half-life estimated in adult PopPK studies, values of the deep compartment volume and flow were fixed to literature values. A 3-compartment model best described the data and was validated by visual predictive checks and non-parametric bootstrap analysis. The final model included body weight as a covariate on all volumes and on both inter-compartmental and elimination clearances. The empiric Bayesian estimates for clearance (CL), volume of distribution at steady state, and terminal half-life were 0.25 (90% CL 0.14-0.36) L/kg/h, 93 (68-174) L/kg, and 266 (197-477) h, respectively. These studies will provide useful information for future PopPK studies of amiodarone in infants and children that could improve dosage regimens. |
19,664 | Feasibility and safety of outpatient cardiac catheterization with intracoronary acetylcholine provocation test. | Intracoronary acetylcholine (ACh) provocation test is useful to diagnose vasospastic angina. Although outpatient coronary angiography has been widely performed in current clinical settings, the feasibility and safety of ACh provocation test in outpatient services are unclear. A total of 323 patients, who electively underwent ACh provocation test in hospitalization and outpatient services, were included. Coronary angiography was performed after insertion of a temporary pacing electrode in the right ventricle. The positive diagnosis of intracoronary ACh provocation test was defined as total or subtotal coronary artery narrowing accompanied by chest pain and/or ischemic electrocardiographic changes. Cardiac complications defined as composite of death, ventricular fibrillation or sustained ventricular tachycardia, myocardial infarction, cardiogenic shock, and cardiac tamponade, were evaluated. There were 201 patients (62%) in the hospitalization group and 122 patients (38%) in the outpatient group. The incidence of positive ACh provocation test was similar between the 2 groups (47 vs. 54%, p = 0.21). Coronary angiography in the outpatient group was performed through the radial artery, mostly (98%) with a 4 F sheath. Venous access site was not significantly different between the 2 groups, and the sheath size was 5 F in all cases. There were 2 cases (1.0%) of cardiac complications in the hospitalization group, whereas 1 case (0.8%), which led to unexpected hospitalization, occurred in the outpatient group. In conclusion, intracoronary ACh provocation test for the diagnosis of vasospastic angina in outpatient services was feasible and safe in selected patients. |
19,665 | Relationship between the prognostic value of ventilatory efficiency and age in patients with heart failure. | Background Ventilatory efficiency decreases with age. This study aimed to investigate the prognostic significance and cut-off value of the minute ventilation/carbon dioxide production (VE/VCO<sub>2</sub>) slope according to age in patients with heart failure. Methods and results We analysed 1501 patients with heart failure from our observational cohort who performed maximal symptom-limited cardiopulmonary exercise testing and separated them into three age groups (≤55 years, 56-70 years and ≥71 years) in total and according to the three ejection fraction categories defined by European Society of Cardiology guidelines. The endpoint was set as heart failure events, hospitalisation for heart failure or death from heart failure. The VE/VCO<sub>2</sub> slope increased with age. During the median follow-up period of 4 years, 141 heart failure (9%) events occurred. In total, univariate Cox analyses showed that the VE/VCO<sub>2</sub> slope (cont.) was significantly related to heart failure events, while on multivariate analysis, the prognostic significance of the VE/VCO<sub>2</sub> slope (cont.) was poor, accompanied by a significant interaction with age ( P < 0.0001). The cut-off value of the VE/VCO<sub>2</sub> slope increased with the increase in age in not only the total but also the sub-ejection fraction categories. Multivariate analyses with a stepwise method adjusted for estimated glomerular filtration rate, peak oxygen consumption, atrial fibrillation and brain natriuretic peptide, showed that the predictive value of the binary VE/VCO<sub>2</sub> slope separated by the cut-off value varied according to age. There was a tendency for the prognostic significance to increase with age irrespective of ejection fraction. Conclusion The prognostic significance and cut-off value of the VE/VCO<sub>2</sub> slope may increase with advancing age. |
19,666 | Modulation of renal sympathetic innervation: recent insights beyond blood pressure control. | Renal afferent and efferent sympathetic nerves are involved in the regulation of blood pressure and have a pathophysiological role in hypertension. Additionally, several conditions that frequently coexist with hypertension, such as heart failure, obstructive sleep apnea, atrial fibrillation, renal dysfunction, and metabolic syndrome, demonstrate enhanced sympathetic activity. Renal denervation (RDN) is an approach to reduce renal and whole body sympathetic activation. Experimental models indicate that RDN has the potential to lower blood pressure and prevent cardio-renal remodeling in chronic diseases associated with enhanced sympathetic activation. Studies have shown that RDN can reduce blood pressure in drug-naïve hypertensive patients and in hypertensive patients under drug treatment. Beyond its effects on blood pressure, sympathetic modulation by RDN has been shown to have profound effects on cardiac electrophysiology and cardiac arrhythmogenesis. RDN can display anti-arrhythmic effects in a variety of animal models for atrial fibrillation and ventricular arrhythmias. The first non-randomized studies demonstrate that RDN may promote the maintenance of sinus rhythm following catheter ablation in patients with atrial fibrillation. Registry data point towards a beneficial effect of RDN to prevent ventricular arrhythmias in patients with heart failure and electrical storm. Further large randomized placebo-controlled trials are needed to confirm the antihypertensive and anti-arrhythmic effects of RDN. Here, we will review the current literature on anti-arrhythmic effects of RDN with the focus on atrial fibrillation and ventricular arrhythmias. We will discuss new insights from preclinical and clinical mechanistic studies and possible clinical implications of RDN. |
19,667 | His Bundle Pacing: Is It Ready for Prime Time? | Long-term right ventricular apical pacing has been associated with detrimental effects, including an increased risk for heart failure, atrial fibrillation, and death. Most of these adverse effects result from ventricular dyssynchrony related to perturbed ventricular depolarization. In addition, biventricular pacing has limited benefits in patients with non-left bundle branch block and severely reduced ejection fraction. Consequently, alternative pacing strategies that mimic natural physiology are desired. Recently, permanent His bundle pacing has emerged as a true physiologic form of ventricular pacing that has been shown to be safe and feasible in clinical practice. |
19,668 | Leadless Pacemakers: State of the Art and Future Perspectives. | Leadless pacemaker therapy is a new technology that aims at avoiding lead- and pocket-related complications of conventional transvenous and epicardial pacing. To date, 2 self-contained leadless pacemakers for right ventricular pacing have been clinically available: the Nanostim Leadless Pacemaker System and the Micra Transcatheter Pacing System. Additionally, a new multicomponent leadless pacemaker for endocardial left ventricular pacing has been proposed as an alternative choice for cardiac resynchronization therapy. In this review, we describe the state of the art of leadless pacing and compare the currently available devices with traditional transvenous leadless pacemakers. |
19,669 | Implantable Cardioverter Defibrillator Implantation with or Without Defibrillation Testing. | Defibrillation testing (DFT) during implantable cardioverter-defibrillator (ICD) implantation is still considered standard of care in some, but in increasingly fewer centers. The goal is to ensure that the device system functions as intended by testing in the controlled laboratory setting. Although safe, complications can occur and DFT is associated with an increased procedural time and cost. DFT is useful in assessing device function when programming changes or patient characteristics raise concerns regarding ICD efficacy. DFT remains standard of practice following implantation of subcutaneous ICDs and other specific circumstances. Implanting physicians should remain familiar with the process of DFT and situations where it is useful for individual patients. |
19,670 | Rest and Stress Longitudinal Systolic Left Ventricular Mechanics in Hypertrophic Cardiomyopathy: Implications for Prognostication. | Exercise intolerance is the most common symptom in hypertrophic cardiomyopathy (HCM). We examined whether inability to augment myocardial mechanics during exercise would influence functional performance and clinical outcomes in HCM.</AbstractText>Ninety-five HCM patients (32 nonobstructive, 32 labile-obstructive, 31 obstructive) and 26 controls of similar age and gender distribution were recruited prospectively. They underwent rest and treadmill stress strain echocardiography, and 61 of them underwent magnetic resonance imaging. Mechanical reserve (MRES) was defined as percent change in systolic strain rate (SR) immediately postexercise.</AbstractText>Global strain and SR were significantly lower in HCM patients at rest (strain: nonobstructive, -15.6 ± 3.0; labile-obstructive, -15.9 ± 3.0; obstructive, -13.8 ± 2.9; control, -17.7% ± 2.1%, P < .001; SR: nonobstructive, -0.92 ± 0.20; labile-obstructive, -0.94 ± 0.17; obstructive, -0.85 ± 0.18; control, -1.04 ± 0.14 s-1</sup>, P = .002); and immediately postexercise (strain: nonobstructive, -15.6 ± 3.0; labile-obstructive, -17.6 ± 3.6; obstructive, -15.6 ± 3.6; control, -19.2 ± 3.1%; P = .001; SR: nonobstructive, -1.41 ± 0.37; labile-obstructive, -1.64 ± 0.38; obstructive, -1.32 ± 0.29; control, -1.82 ± 0.29 s-1</sup>, P < .001). MRES was lower in nonobstructive and obstructive compared with labile-obstructive and controls (51% ± 29%, 54% ± 31%, 78% ± 38%, 77% ± 30%, P = .001, respectively). Postexercise SR and MRES were associated with exercise capacity (r = 0.47 and 0.42, P < .001 both, respectively). When adjusted for age, gender, body mass index, E/e', and resting peak instantaneous systolic gradient, postexercise SR best predicted exercise capacity (r = 0.74, P = .003). Postexercise SR was correlated with extent of late gadolinium enhancement (r = 0.34, P = .03). By Cox regression, exercise SR and MRES predicted ventricular tachycardia/ventricular fibrillation (VT/VF) even after adjustment for age, gender, family history of sudden cardiac death, septum ≥ 3 cm and abnormal blood pressure response (P = .04 and P = .046, respectively).</AbstractText>Nonobstructive and obstructive patients have reduced MRES compared with labile-obstructive and controls. Postexercise SR correlates with LGE and exercise capacity. Exercise SR and MRES predict VT/VF.</AbstractText>Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
19,671 | Significant impact of electrical storm on mortality in patients with structural heart disease and an implantable cardiac defibrillator. | Electrical storm (E-Storm), defined as multiple episodes of ventricular arrhythmias within a short period of time, is an important clinical problem in patients with an implantable cardiac defibrillator (ICD) including cardiac resynchronization therapy devices capable of defibrillation. The detailed clinical aspects of E-Storm in large populations especially for non-ischemic dilated cardiomyopathy (DCM), however, remain unclear.</AbstractText>This study was performed to elucidate the detailed clinical aspects of E-Storm, such as its predictors and prevalence among patients with structural heart disease including DCM.</AbstractText>We analyzed the data of the Nippon Storm Study, which was a prospective observational study involving 1570 patients enrolled from 48 ICD centers. For the purpose of this study, we evaluated 1274 patients with structural heart disease, including 482 (38%) patients with ischemic heart disease (IHD) and 342 (27%) patients with DCM.</AbstractText>During a median follow-up of 28months (interquartile range: 23 to 33months), E-Storm occurred in 84 (6.6%) patients. The incidence of E-Storm was not significantly different between patients with IHD and patients with DCM (log-rank p=0.52). Proportional hazard regression analyses showed that ICD implantation for secondary prevention of sudden cardiac death (p=0.0001) and QRS width (p=0.015) were the independent risk factors for E-storm. In a comparison between patients with and without E-Storm, survival curves after adjustment for clinical characteristics showed a significant difference in mortality.</AbstractText>E-Storm was associated with subsequent mortality in patients with structural heart disease including DCM.</AbstractText>Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.</CopyrightInformation> |
19,672 | Evaluation of Vasopressin for Vasoplegic Shock in Patients With Preoperative Left Ventricular Dysfunction After Cardiac Surgery: A Propensity-Score Analysis. | Postoperative vasoplegic shock after cardiac surgery seems to be a frequent complication with poor outcomes. We hypothesized that vasopressin may increase the risk of poor outcomes in patients with preoperative Left Ventricular Dysfunction (pLVD) rather than norepinephrine. The aim of this study was to assess whether vasopressin is superior to norepinephrine to improve outcomes in patients with pLVD after cardiac surgery.</AbstractText>This retrospective cohort study included 1,156 patients with postoperative vasoplegic shock (mean arterial pressure <65 mmHg resistant to fluid challenge and cardiac index >2.20 L/min m) and pLVD (left ventricular ejection fraction ≤35%, left ventricular end-diastolic diameter ≥60 mm, New York Heart Association ≥III) from 2007 to 2017. To address any indicated biases, we derived a propensity score predicting the functions of vasopressin (0.02-0.07 U/min) and norepinephrine (10-60 μg/min) on postoperative vasoplegic shock. The primary outcomes were 30-day mortality, mechanical ventilation more than 48 h, cardiac reoperation, extracorporeal membrane oxygenation, stroke, and acute kidney injury, whereas the secondary outcomes included infection, septic shock, atrial fibrillation and ventricular arrhythmias.</AbstractText>There were 338 patients (169 vasopressin and169 norepinephrine) with a similar risk profile in propensity score-matched cohort. In propensity-matched patients, the primary outcomes of vasopressin and norepinephrine showed no significant difference (50.89% vs. 58.58%, P = 0.155). However, compared with norepinephrine, secondary outcomes of vasopressin were increased due to the high rate of atrial fibrillation (11.83% vs. 20.12%, P = 0.038) and ventricular arrhythmias (14.20% vs. 24.85%, P = 0.014).</AbstractText>Compared with norepinephrine, vasopressin could not improve the postoperative outcomes in patients with pLVD after cardiac surgery. Vasopressin should be cautious to be used as a first-line vasopressor agent in postcardiac vasoplegic shock.</AbstractText> |
19,673 | Association of left ventricular late gadolinium enhancement with left atrial low voltage areas in patients with atrial fibrillation. | Presence of late gadolinium enhancement (LGE) is related to adverse cardiovascular outcome. Many patients suffering from atrial fibrillation (AF) undergo cardiovascular magnetic resonance (CMR) imaging prior to ablation. Since quantification of atrial fibrosis still lacks reproducibility, we sought to investigate risk factors for the presence of left ventricular (LV)-LGE and a possible correlation between ventricular fibrosis as defined by positive LGE and pathological atrial voltage maps evaluated by 3D mapping systems.</AbstractText>Between May 2015 and January 2017, 241 patients with AF (73% persistent AF, 71% male, mean age 62.8 ± 10.1 years, Redo procedure in 24%, AF history 4.5 ± 5.2 years) underwent CMR including LV LGE prior to pulmonary vein (PV) isolation at Heart Center Leipzig. Depending on CMR results, two groups were separated: 'LV-LGE negative' (Group A, n = 197, 82%) and 'LV-LGE positive' (Group B, n = 44, 18%). To identify low voltage areas (LVA), a 3D electro-anatomic map was created during PV isolation. Multivariate analysis revealed male gender [odds ratio (OR) 7.6, 95% confidence interval (95% CI) 2.4-23.9, P = 0.001] and an increased CHA2DS2VASc Score (OR 1.6, 95% CI 1.2-2.2, P = 0.004) as significantly associated with LV-LGE. Impaired left ventricular ejection fraction, LV dilatation, larger LA size and, enlarged septum diameter occurred significantly more often in the 'LGE positive' group. Low voltage areas were detected in 83 patients overall (34%): Group A: n = 64/197 (33%), Group B: n = 19/44 (43%) (P = 0.177).</AbstractText>Male gender and high CHA2DS2VASc Score are significantly associated with presence of LV-LGE, but LV-LGE is not associated with left atrial LVA.</AbstractText> |
19,674 | Survival factors of hospitalized out-of-hospital cardiac arrest patients in Taiwan: A retrospective study. | The chain of survival has been shown to improve the chances of survival for victims of cardiac arrest. Post-cardiac arrest care has been demonstrated to significantly impact the survival of out-of-hospital cardiac arrest (OHCA). How post-cardiac arrest care influences the survival of OHCA patients has been a main concern in recent years. The objective of this study was to assess the survival outcome of hospitalized OHCA patients and determine the factors associated with improved survival in terms of survival to discharge. We conducted a retrospective observational study by analyzing records from the National Health Insurance Research Database of Taiwan from 2007 to 2013. We collected cases with an International Classification of Disease Clinical Modification, 9th revision primary diagnosis codes of 427.41 (ventricular fibrillation, VF) or 427.5 (cardiac arrest) and excluded patients less than 18 years old, as well as cases with an unknown outcome or a combination of traumatic comorbidities. We then calculated the proportion of survival to discharge among hospitalized OHCA patients. Factors associated with the dependent variable were examined by logistic regression. Statistical analysis was conducted using SPSS 22 (IBM, Armonk, NY). Of the 11,000 cases, 2,499 patients (22.7%) survived to hospital discharge. The mean age of subjects who survived to hospital discharge and those who did not was 66.7±16.7 and 71.7±15.2 years, respectively. After adjusting for covariates, neurological failure, cardiac comorbidities, hospital level, intensive care unit beds, transfer to another hospital, and length of hospital stay were independent predictors of improved survival. Cardiac rhythm on admission was a strong factor associated with survival to discharge (VF vs. non-VF: adjusted odds ratio: 3.51; 95% confidence interval: 3.06-4.01). In conclusion, cardiac comorbidities, hospital volume, cardiac rhythm on admission, transfer to another hospital and length of hospital stay had a significant positive association with survival to discharge in hospitalized OHCA patients in Taiwan. |
19,675 | Association between paced QRS duration and atrial fibrillation after permanent pacemaker implantation: A retrospective observational cohort study. | Right ventricular pacing often results in prolonged QRS duration (QRSd) as the result of right ventricular stimulation, and atrial fibrillation (AF) may result. The association of pacing-induced prolonged QRSd and AF in patients with permanent pacemakers is unknown.We selected 180 consecutive patients who underwent pacemaker implantation for complete/advanced atrioventricular block. All of the patients were paced from the right ventricular septum. Electrocardiography recordings were obtained at the beginning and the end of pacemaker implantation. QRSd was measured in all 12 leads. The QRSd variation was calculated by subtracting the preimplantation QRSd from the postimplantation QRSd.The occurrence of AF was observed in 64 (35.56%) patients (follow-up 33.62 ± 21.47 mo). No significant differences in preimplantation QRSd were observed between the AF occurrence and nonoccurrence groups. The QRSd variation in leads V4 (54.22 ± 29.03 vs 42.66 ± 33.79 ms, P = .022), and V6 (64.62 ± 23.16 vs 48.45 ± 34.40 ms, P = .001) differed significantly between the occurrence and nonoccurrence groups. More QRSd variation in lead V6 (P = .005, HR = 1.822, 95% CI 1.174-2.718, interval scale of QRSd was 40 ms) and left atrial diameter (P = .045, HR = 1.042, 95% CI 1.001-1.086) were independent risk factors for AF occurrence. Receiver operating characteristic curve suggested that QRSd variation in lead V6 could predict AF occurrence, especially for patients with long preimplantation QRSd (≥120 ms, area under the curve was 0.826, 95% CI 0.685-0.967).QRSd variation in lead V6 might be positively correlated with postimplantation AF occurrence. In patients with pacemaker implantation, QRSd could be a complementary criterion for optimizing the right ventricular septal pacing site, and smallest QRSd might be worth pursuing. |
19,676 | Assesment of Rhythm Disorders in Classical and Nonclassical Mitral Valve Prolapse. | Mitral Valve Prolapse (MVP) is the most common cardiac valve pathology of to day. Aim of article was to identify the types and frequency of potentially malignant arrhythmia and atrial brillation in patients with MVP, to determine the differences in these arrhythmias between classical and non-classical MVP, to evaluate the correlation of potentially malignant arrhythmia and atrial fibrillation with MVP with possible clinical complications of arrhythmogenic sudden cardiac death and potential risk of thromboembolic vascular incident.</AbstractText>Article has retrospective-prospective analytical character and present observational study on 239 patients (120 with MVP (66 with classical and 54 with non-classical MVP), who had a subjective feeling of palpitations and/or pain in the chest, and/or episode of syncope, and did not have ischemic heart disease or another valve pathology) and 119 healthy patients in the control group. All patients were analyzed by 24-hour ECG Holter.</AbstractText>Signifficant difference in all analyzed arrhythmias between classical MVP and control group (p <0.001) between non-classical and control group in the presence of preexcitation signs (p = 0.047), and between classical and non-classical in presence of QT prolongation and AV block of II and III degree (p = 0.023), ventricular arrhythmias of the 3rd, 4th and 5th grade at scales according to Lown (p = 0.002) and atrial brillation in favor of classical MVP (p = 0.016).</AbstractText>The potential risk of cardiac death and vascular incidence is signi cantly higher in classical MVP than in non-classical MVP, implying the need for routine ECG-Holter monitoring in their diagnosis for timely prevention of clinical arrhythmogenic complications.</AbstractText> |
19,677 | Interventional Left Atrial Appendage Closure Affects the Metabolism of Acylcarnitines. | Left atrial appendage closure (LAAC) represents the interventional alternative to oral anticoagulation for stroke prevention in atrial fibrillation (AF). The metabolism of acylcarnitines was shown to affect cardiovascular diseases. This study evaluates the influence of successful LAAC on the metabolism of acylcarnitines.</AbstractText>Patients undergoing successful LAAC were enrolled prospectively. Peripheral blood samples for metabolomics measurements were collected immediately before (i.e., index) and six months after LAAC (i.e., mid-term). A targeted metabolomics analysis based on electrospray ionization-liquid chromatography-mass spectrometry (ESI-LC-MS/MS) and MS/MS measurements was performed.</AbstractText>44 patients with non-valvular AF (median CHA₂DS₂-VASc score 4, median HAS-BLED score 4) and successful LAAC were included. Significant changes in acylcarnitine levels were found in the total cohort, which were mainly attributed to patients with impaired left ventricular and renal function, elevated amino-terminal pro-brain natriuretic peptide (NT-proBNP) and diabetes mellitus. Adjusted multivariable regression models revealed significant changes of five metabolites over mid-term follow-up: C2, C14:1, C16, and C18:1 decreased significantly (each p</i> < 0.05); short-chain C5 acylcarnitine plasma levels increased significantly (p</i> < 0.05).</AbstractText>This study demonstrates that successful LAAC affects the metabolism of acylcarnitines at mid-term follow-up.</AbstractText>ClinicalTrials.gov Identifier: NCT02985463.</AbstractText> |
19,678 | Evaluation of chest compression artefact removal based on rhythm assessments made by clinicians. | To evaluate the performance of a state-of-the-art cardiopulmonary resuscitation (CPR) artefact suppression method by assessing to what extent the filtered electrocardiogram (ECG) can be correctly diagnosed by emergency medicine doctors.</AbstractText>A total of 819 ECG segments were used. Each segment contained two consecutive 10 s intervals, an artefact free interval and an interval corrupted by CPR artefacts. Each ECG segment was digitally processed to remove CPR artefacts using an adaptive filter. Each ECG segment was split into artefact-free and filtered intervals, randomly reordered for dissociation, and independently offered to four reviewers for rhythm annotation. The rhythm annotations of the artefact-free intervals were considered as the gold standard against which the rhythm annotations of the filtered intervals were evaluated. For the filtered intervals, the rater agreement (κ, Kappa score) with the gold standard, the sensitivity and the specificity were computed individually for each reviewer, and jointly through the majority decision of the pool of reviewers (DPR). These results were also compared to those obtained using a commercial shock advisory algorithm (SAA).</AbstractText>The agreement between each reviewer and the gold standard was moderate ranging between κ = 0.41-0.64. The sensitivities and specificities ranged between 64.3-95.0%, and 70.0-95.9%, respectively. The agreement for the DPR was substantial with κ = 0.64 (0.62-0.66), a sensitivity of 90.6%, and a specificity of 85.6%. For the SAA, the agreement was fair with κ = 0.33 (0.31-0.35), a sensitivity of 90.3%, and a specificity of 66.4%.</AbstractText>Clinicians outperformed the SAA, but specificities remained below the specifications recommended by the American Heart Association. Visual assessment of the filtered ECG by clinicians is not reliable enough, and varies greatly among clinicians. Results considerably improve by considering the consensus decision of a pool of clinicians.</AbstractText>Copyright © 2018 Elsevier B.V. All rights reserved.</CopyrightInformation> |
19,679 | [Implantable cardioverter defibrillators in the prevention of sudden cardiac death]. | The article highlights the role of implantable cardioverter defibrillators (ICDs) in the primary and secondary prevention of sudden cardiac death. It considers the results of multicenter studies comparing the efficacy of antiarrhythmic drugs and implantable devices in the primary and secondary prevention of sudden cardiac death, including that in patients with nonischemic cardiomyopathy and discusses quality of life in patients with ICDs.</Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Bockeria</LastName><ForeName>L A</ForeName><Initials>LA</Initials><AffiliationInfo><Affiliation>I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia, Moscow, Russia.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Neminushchiy</LastName><ForeName>N M</ForeName><Initials>NM</Initials><AffiliationInfo><Affiliation>I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia, Moscow, Russia.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Mikhaylichenko</LastName><ForeName>S I</ForeName><Initials>SI</Initials><AffiliationInfo><Affiliation>N.N. Burdenko Main Military Clinical Hospital, Ministry of Defense of the Russian Federation, Moscow, Russia.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Novichkov</LastName><ForeName>S A</ForeName><Initials>SA</Initials><AffiliationInfo><Affiliation>N.N. Burdenko Main Military Clinical Hospital, Ministry of Defense of the Russian Federation, Moscow, Russia.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Achkasov</LastName><ForeName>E E</ForeName><Initials>EE</Initials><AffiliationInfo><Affiliation>I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia, Moscow, Russia.</Affiliation></AffiliationInfo></Author></AuthorList><Language>rus</Language><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType><PublicationType UI="D019531">Lecture</PublicationType></PublicationTypeList><VernacularTitle>Implantiruemye kardiovertery-defibrilliatory v profilaktike vnezapnoĭ serdechnoĭ smerti.</VernacularTitle></Article><MedlineJournalInfo><Country>Russia (Federation)</Country><MedlineTA>Ter Arkh</MedlineTA><NlmUniqueID>2984818R</NlmUniqueID><ISSNLinking>0040-3660</ISSNLinking></MedlineJournalInfo><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D016757" MajorTopicYN="N">Death, Sudden, Cardiac</DescriptorName><QualifierName UI="Q000209" MajorTopicYN="N">etiology</QualifierName><QualifierName UI="Q000517" MajorTopicYN="Y">prevention & control</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D017147" MajorTopicYN="N">Defibrillators, Implantable</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D004554" MajorTopicYN="N">Electric Countershock</DescriptorName><QualifierName UI="Q000295" MajorTopicYN="N">instrumentation</QualifierName><QualifierName UI="Q000379" MajorTopicYN="N">methods</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D006801" MajorTopicYN="N">Humans</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D011788" MajorTopicYN="Y">Quality of Life</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D055502" MajorTopicYN="N">Secondary Prevention</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D014693" MajorTopicYN="Y">Ventricular Fibrillation</DescriptorName><QualifierName UI="Q000523" MajorTopicYN="N">psychology</QualifierName><QualifierName UI="Q000628" MajorTopicYN="N">therapy</QualifierName></MeshHeading></MeshHeadingList><OtherAbstract Type="Publisher" Language="rus">В статье освещается роль имплантируемых кардиовертеров-дефибрилляторов (ИКД) в первичной и вторичной профилактике внезапной смерти. Рассматриваются результаты многоцентровых исследований, направленных на сравнение эффективности антиаритмических препаратов и имплантируемых устройств в первичной и вторичной профилактике внезапной смерти, в том числе у пациентов с неишемической кардиомиопатией, обсуждается вопрос качества жизни больных с ИКД. |
19,680 | Central Sleep Apnea with Cheyne-Stokes Breathing in Heart Failure - From Research to Clinical Practice and Beyond. | Characterized by periodic crescendo-decrescendo pattern of breathing alternating with central apneas, Central sleep apnea (CSA) with Cheyne-Stokes Breathing represents a highly prevalent, yet underdiagnosed comorbidity in chronic heart failure (CHF). A diverse body of evidence demonstrates increased morbidity and mortality in the presence of CSB. CSB has been described in both CHF patients with preserved and reduced ejection fraction, regardless of drug treatment. Risk factors for CSB are older age, male gender, high BMI, atrial fibrillation and hypocapnia.The pathophysiology of CSB has been explained by the loop gain theory, where a controller (the respiratory center) and a plant (the lungs) are operating in a reciprocal relationship (negative feedback) to regulate a key parameter (partial pressure of carbon dioxide (pCO<sub>2</sub>)). The temporal interaction between these elements is dependent on the circulatory delay. Increased chemosensitivity/chemoresponsiveness of the respiratory center and/or augmented ascending non- CO<sub>2</sub> stimuli from the C-fibers in the lungs (interstitial pulmonary edema), overly efficient ventilation when breathing at low volumes and prolonged circulation time are involved. An alternative hypothesis of CSB being an adaptive response of the failing heart has its merits as well. The clinical manifestation of CSB is usually poor, lacking striking symptoms and complaints. Witnessed apneas and snoring are infrequently reported by the sleep partner. Sometimes patients may report poor sleep quality with frequent awakenings, paroxysmal nocturnal dyspnea and frequent urination at night. Standard instrumental and laboratory studies, performed in CHF patients, may present clues to the presence of CSB. Concentric remodeling of the left ventricle and dilated left atrium (echocardiography), high BNP and C-reactive protein levels, increased ventilation-carbon dioxide output (VEVCO<sub>2</sub>) and lower end-tidal CO<sub>2</sub> (cardiopulmonary exercise testing), reduced diffusion capacity (pulmonary function testing) and hypocapnia (blood-gas analysis) may indicate the presence of CSB.CSB and cardiovascular disease are probably linked through bidirectional causality. Cyclic variations in heart rate, blood pressure, respiratory volume, partial pressure of arterial oxygen (pO<sub>2</sub>) and pCO<sub>2</sub> lead to sympathetic-adrenal activation. The latter worsens ventricular energetism and survival of cardiomyocytes and exerts antiarhythmogenic effects. It causes cardiac remodeling, potentiating the progression and the lethal outcome in CHF patients. Several treatment modalities have been proposed in CSB. The most commonly used are continuous positive airway pressure (CPAP), adaptive servoventilation (ASV) and nocturnal home oxygen therapy (HOT). Novel therapies like nocturnal supplemental CO<sub>2</sub> and phrenic nerve stimulation are being tested recently. The current treatment recommendations (by the American Academy of Sleep Medicine) are for CPAP and HOT as standard therapies, while ASV is an option only in patients with EF > 45%. BPAP (bilevel device) remains an option only when there is no adequate response to previous modes of treatment. Acetazolamide and theophylline are options only after failing the above modalities and if accompanied by a close follow-up. |
19,681 | Athletes with channelopathy may be eligible to play. | The European and Bethesda recommendations roughly state that any athlete with channelopathy is not eligible to participate in sports on a presumed risk of potentially life-threatening ventricular tachycardia or fibrillation. However, eligibility decision-making on a presumed risk of ventricular tachycardia or fibrillation is debatable. Channelopathies are primary electrical cardiac disorders and are usually transmitted as an autosomal dominant trait. Some of the channelopathies are potentially fatal in relation to exercise and predispose to life-threatening cardiac arrhythmias including ventricular tachycardia or fibrillation. Exercise, swimming, body heating and electrolyte depletion can all act as a trigger of ventricular tachycardia or fibrillation in channelopathy. However, new research mentioned a very low incidence of ventricular tachycardia or fibrillation in athletes with channelopathy challenging the decision of disqualification. Recently, the American recommendations for sports participation in athletes with a cardiovascular disorder have updated their eligibility decision-making.In this manuscript we describe the signature features of the electrocardiogram changes in channelopathies and we argue that new research data should allow for the introduction of more liberal eligibility decision-making for sports participation in athletes with channelopathy, not only in the United States but also in European countries. |
19,682 | Prevalence and Predictors of Arrhythmia in Patients with Obstructive Sleep Apnea. | To assess the prevalence and types of arrhythmias in Saudi OSA patients and to identify predictors of arrhythmia in this group of patients.</AbstractText>This case-control study included all patients who underwent level I attended overnight polysomnography between 2009 and 2012. Electrocardiographic data collected during sleep studies of patients with and without OSA were manually reviewed.</AbstractText>The study comprised 498 patients (394 OSA patients and 104 non-OSA patients (controls). The prevalence of arrhythmia in OSA patients was higher than that in the controls (26.9% vs. 11.5%; p=0.001). Comparing OSA patients and controls showed: premature atrial contraction (10.2%vs.2.9%;p=0.019), premature ventricular contraction (PVC) (19.3%vs.9.6%;p=0.02), non-isolated PVC (bi/tri/qua) 10.8%vs.2.3%;p=0.04) and atrial fibrillation (1.6%vs.0%;p=0.001). Multiple logistic regression analysis revealed that, patients with OSA had twice the odds of having any cardiac arrhythmia (OR 1.91; CI 95% 1.27-3.11; p <0.05).</AbstractText>Patients with OSA had a higher prevalence of arrhythmia compared to controls, and OSA is a predictor of arrhythmia during sleep.</AbstractText> |
19,683 | Sympathetic Nervous Regulation of Calcium and Action Potential Alternans in the Intact Heart.<Pagination><StartPage>16</StartPage><MedlinePgn>16</MedlinePgn></Pagination><ELocationID EIdType="pii" ValidYN="Y">16</ELocationID><ELocationID EIdType="doi" ValidYN="Y">10.3389/fphys.2018.00016</ELocationID><Abstract><AbstractText><b>Rationale:</b> Arrhythmogenic cardiac alternans are thought to be an important determinant for the initiation of ventricular fibrillation. There is limited information on the effects of sympathetic nerve stimulation (SNS) on alternans in the intact heart and the conclusions of existing studies, focused on investigating electrical alternans, are conflicted. Meanwhile, several lines of evidence implicate instabilities in Ca handling, not electrical restitution, as the primary mechanism underpinning alternans. Despite this, there have been no studies on Ca alternans and SNS in the intact heart. The present study sought to address this, by application of voltage and Ca optical mapping for the simultaneous study of APD and Ca alternans in the intact guinea pig heart during direct SNS. <b>Objective</b>: To determine the effects of SNS on APD and Ca alternans in the intact guinea pig heart and to examine the mechanism(s) by which the effects of SNS are mediated. <b>Methods and Results</b>: Studies utilized simultaneous voltage and Ca optical mapping in isolated guinea pig hearts with intact innervation. Alternans were induced using a rapid dynamic pacing protocol. SNS was associated with rate-independent shortening of action potential duration (APD) and the suppression of APD and Ca alternans, as indicated by a shift in the alternans threshold to faster pacing rates. Qualitatively similar results were observed with exogenous noradrenaline perfusion. In contrast with previous reports, both SNS and noradrenaline acted to flatten the slope of the electrical restitution curve. Pharmacological block of the slow delayed rectifying potassium current (I<sub>Ks</sub>), sufficient to abolish I<sub>Ks</sub>-mediated APD-adaptation, partially reversed the effects of SNS on pacing-induced alternans. Treatment with cyclopiazonic acid, an inhibitor of the sarco(endo)plasmic reticulum ATPase, had opposite effects to that of SNS, acting to increase susceptibility to alternans, and suggesting that accelerated Ca reuptake into the sarcoplasmic reticulum is a major mechanism by which SNS suppresses alternans in the guinea pig heart. <b>Conclusions</b>: SNS suppresses calcium and action potential alternans in the intact guinea pig heart by an action mediated through accelerated Ca handling and via increased I<sub>Ks</sub>.</AbstractText></Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Winter</LastName><ForeName>James</ForeName><Initials>J</Initials><AffiliationInfo><Affiliation>School of Cardiovascular Medicine and Sciences, King's College London, United Kingdom.</Affiliation></AffiliationInfo><AffiliationInfo><Affiliation>Institute of Cardiovascular Sciences, College of Medicine and Dental Sciences, University of Birmingham, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Bishop</LastName><ForeName>Martin J</ForeName><Initials>MJ</Initials><AffiliationInfo><Affiliation>Biomedical Engineering Department, King's College London, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Wilder</LastName><ForeName>Catherine D E</ForeName><Initials>CDE</Initials><AffiliationInfo><Affiliation>School of Cardiovascular Medicine and Sciences, King's College London, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>O'Shea</LastName><ForeName>Christopher</ForeName><Initials>C</Initials><AffiliationInfo><Affiliation>Institute of Cardiovascular Sciences, College of Medicine and Dental Sciences, University of Birmingham, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Pavlovic</LastName><ForeName>Davor</ForeName><Initials>D</Initials><AffiliationInfo><Affiliation>Institute of Cardiovascular Sciences, College of Medicine and Dental Sciences, University of Birmingham, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Shattock</LastName><ForeName>Michael J</ForeName><Initials>MJ</Initials><AffiliationInfo><Affiliation>School of Cardiovascular Medicine and Sciences, King's College London, United Kingdom.</Affiliation></AffiliationInfo></Author></AuthorList><Language>eng</Language><GrantList CompleteYN="Y"><Grant><GrantID>FS/16/35/31952</GrantID><Acronym>BHF_</Acronym><Agency>British Heart Foundation</Agency><Country>United Kingdom</Country></Grant><Grant><GrantID>MR/N011007/1</GrantID><Acronym>MRC_</Acronym><Agency>Medical Research Council</Agency><Country>United Kingdom</Country></Grant><Grant><GrantID>RG/12/4/29426</GrantID><Acronym>BHF_</Acronym><Agency>British Heart Foundation</Agency><Country>United Kingdom</Country></Grant></GrantList><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType></PublicationTypeList><ArticleDate DateType="Electronic"><Year>2018</Year><Month>01</Month><Day>23</Day></ArticleDate></Article><MedlineJournalInfo><Country>Switzerland</Country><MedlineTA>Front Physiol</MedlineTA><NlmUniqueID>101549006</NlmUniqueID><ISSNLinking>1664-042X</ISSNLinking></MedlineJournalInfo><KeywordList Owner="NOTNLM"><Keyword MajorTopicYN="N">action potential duration</Keyword><Keyword MajorTopicYN="N">alternans</Keyword><Keyword MajorTopicYN="N">calcium transient</Keyword><Keyword MajorTopicYN="N">intact heart</Keyword><Keyword MajorTopicYN="N">optical mapping</Keyword><Keyword MajorTopicYN="N">sarco(endo)plasmic reticulum ATPase</Keyword><Keyword MajorTopicYN="N">sympathetic nervous system</Keyword><Keyword MajorTopicYN="N">ventricular fibrillation</Keyword></KeywordList></MedlineCitation><PubmedData><History><PubMedPubDate PubStatus="received"><Year>2017</Year><Month>9</Month><Day>27</Day></PubMedPubDate><PubMedPubDate PubStatus="accepted"><Year>2018</Year><Month>1</Month><Day>8</Day></PubMedPubDate><PubMedPubDate PubStatus="entrez"><Year>2018</Year><Month>2</Month><Day>8</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="pubmed"><Year>2018</Year><Month>2</Month><Day>8</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="medline"><Year>2018</Year><Month>2</Month><Day>8</Day><Hour>6</Hour><Minute>1</Minute></PubMedPubDate></History><PublicationStatus>epublish</PublicationStatus><ArticleIdList><ArticleId IdType="pubmed">29410631</ArticleId><ArticleId IdType="pmc">PMC5787134</ArticleId><ArticleId IdType="doi">10.3389/fphys.2018.00016</ArticleId></ArticleIdList><ReferenceList><Reference><Citation>Bers D. 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<PubmedBookArticle><BookDocument><PMID Version="1">20301308</PMID><ArticleIdList><ArticleId IdType="bookaccession">NBK1129</ArticleId></ArticleIdList><Book><Publisher><PublisherName>University of Washington, Seattle</PublisherName><PublisherLocation>Seattle (WA)</PublisherLocation></Publisher><BookTitle book="gene">GeneReviews<sup>®</sup></BookTitle><PubDate><Year>1993</Year></PubDate><BeginningDate><Year>1993</Year></BeginningDate><EndingDate><Year>2023</Year></EndingDate><AuthorList Type="editors" CompleteYN="Y"><Author ValidYN="Y"><LastName>Adam</LastName><ForeName>Margaret P</ForeName><Initials>MP</Initials></Author><Author ValidYN="Y"><LastName>Mirzaa</LastName><ForeName>Ghayda M</ForeName><Initials>GM</Initials></Author><Author ValidYN="Y"><LastName>Pagon</LastName><ForeName>Roberta A</ForeName><Initials>RA</Initials></Author><Author ValidYN="Y"><LastName>Wallace</LastName><ForeName>Stephanie E</ForeName><Initials>SE</Initials></Author><Author ValidYN="Y"><LastName>Bean</LastName><ForeName>Lora JH</ForeName><Initials>LJH</Initials></Author><Author ValidYN="Y"><LastName>Gripp</LastName><ForeName>Karen W</ForeName><Initials>KW</Initials></Author><Author ValidYN="Y"><LastName>Amemiya</LastName><ForeName>Anne</ForeName><Initials>A</Initials></Author></AuthorList><Medium>Internet</Medium></Book><ArticleTitle book="gene" part="rws">Long QT Syndrome | <b>Rationale:</b> Arrhythmogenic cardiac alternans are thought to be an important determinant for the initiation of ventricular fibrillation. There is limited information on the effects of sympathetic nerve stimulation (SNS) on alternans in the intact heart and the conclusions of existing studies, focused on investigating electrical alternans, are conflicted. Meanwhile, several lines of evidence implicate instabilities in Ca handling, not electrical restitution, as the primary mechanism underpinning alternans. Despite this, there have been no studies on Ca alternans and SNS in the intact heart. The present study sought to address this, by application of voltage and Ca optical mapping for the simultaneous study of APD and Ca alternans in the intact guinea pig heart during direct SNS. <b>Objective</b>: To determine the effects of SNS on APD and Ca alternans in the intact guinea pig heart and to examine the mechanism(s) by which the effects of SNS are mediated. <b>Methods and Results</b>: Studies utilized simultaneous voltage and Ca optical mapping in isolated guinea pig hearts with intact innervation. Alternans were induced using a rapid dynamic pacing protocol. SNS was associated with rate-independent shortening of action potential duration (APD) and the suppression of APD and Ca alternans, as indicated by a shift in the alternans threshold to faster pacing rates. Qualitatively similar results were observed with exogenous noradrenaline perfusion. In contrast with previous reports, both SNS and noradrenaline acted to flatten the slope of the electrical restitution curve. Pharmacological block of the slow delayed rectifying potassium current (I<sub>Ks</sub>), sufficient to abolish I<sub>Ks</sub>-mediated APD-adaptation, partially reversed the effects of SNS on pacing-induced alternans. Treatment with cyclopiazonic acid, an inhibitor of the sarco(endo)plasmic reticulum ATPase, had opposite effects to that of SNS, acting to increase susceptibility to alternans, and suggesting that accelerated Ca reuptake into the sarcoplasmic reticulum is a major mechanism by which SNS suppresses alternans in the guinea pig heart. <b>Conclusions</b>: SNS suppresses calcium and action potential alternans in the intact guinea pig heart by an action mediated through accelerated Ca handling and via increased I<sub>Ks</sub>.</Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Winter</LastName><ForeName>James</ForeName><Initials>J</Initials><AffiliationInfo><Affiliation>School of Cardiovascular Medicine and Sciences, King's College London, United Kingdom.</Affiliation></AffiliationInfo><AffiliationInfo><Affiliation>Institute of Cardiovascular Sciences, College of Medicine and Dental Sciences, University of Birmingham, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Bishop</LastName><ForeName>Martin J</ForeName><Initials>MJ</Initials><AffiliationInfo><Affiliation>Biomedical Engineering Department, King's College London, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Wilder</LastName><ForeName>Catherine D E</ForeName><Initials>CDE</Initials><AffiliationInfo><Affiliation>School of Cardiovascular Medicine and Sciences, King's College London, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>O'Shea</LastName><ForeName>Christopher</ForeName><Initials>C</Initials><AffiliationInfo><Affiliation>Institute of Cardiovascular Sciences, College of Medicine and Dental Sciences, University of Birmingham, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Pavlovic</LastName><ForeName>Davor</ForeName><Initials>D</Initials><AffiliationInfo><Affiliation>Institute of Cardiovascular Sciences, College of Medicine and Dental Sciences, University of Birmingham, United Kingdom.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Shattock</LastName><ForeName>Michael J</ForeName><Initials>MJ</Initials><AffiliationInfo><Affiliation>School of Cardiovascular Medicine and Sciences, King's College London, United Kingdom.</Affiliation></AffiliationInfo></Author></AuthorList><Language>eng</Language><GrantList CompleteYN="Y"><Grant><GrantID>FS/16/35/31952</GrantID><Acronym>BHF_</Acronym><Agency>British Heart Foundation</Agency><Country>United Kingdom</Country></Grant><Grant><GrantID>MR/N011007/1</GrantID><Acronym>MRC_</Acronym><Agency>Medical Research Council</Agency><Country>United Kingdom</Country></Grant><Grant><GrantID>RG/12/4/29426</GrantID><Acronym>BHF_</Acronym><Agency>British Heart Foundation</Agency><Country>United Kingdom</Country></Grant></GrantList><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType></PublicationTypeList><ArticleDate DateType="Electronic"><Year>2018</Year><Month>01</Month><Day>23</Day></ArticleDate></Article><MedlineJournalInfo><Country>Switzerland</Country><MedlineTA>Front Physiol</MedlineTA><NlmUniqueID>101549006</NlmUniqueID><ISSNLinking>1664-042X</ISSNLinking></MedlineJournalInfo><KeywordList Owner="NOTNLM"><Keyword MajorTopicYN="N">action potential duration</Keyword><Keyword MajorTopicYN="N">alternans</Keyword><Keyword MajorTopicYN="N">calcium transient</Keyword><Keyword MajorTopicYN="N">intact heart</Keyword><Keyword MajorTopicYN="N">optical mapping</Keyword><Keyword MajorTopicYN="N">sarco(endo)plasmic reticulum ATPase</Keyword><Keyword MajorTopicYN="N">sympathetic nervous system</Keyword><Keyword MajorTopicYN="N">ventricular fibrillation</Keyword></KeywordList></MedlineCitation><PubmedData><History><PubMedPubDate PubStatus="received"><Year>2017</Year><Month>9</Month><Day>27</Day></PubMedPubDate><PubMedPubDate PubStatus="accepted"><Year>2018</Year><Month>1</Month><Day>8</Day></PubMedPubDate><PubMedPubDate PubStatus="entrez"><Year>2018</Year><Month>2</Month><Day>8</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="pubmed"><Year>2018</Year><Month>2</Month><Day>8</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="medline"><Year>2018</Year><Month>2</Month><Day>8</Day><Hour>6</Hour><Minute>1</Minute></PubMedPubDate></History><PublicationStatus>epublish</PublicationStatus><ArticleIdList><ArticleId IdType="pubmed">29410631</ArticleId><ArticleId IdType="pmc">PMC5787134</ArticleId><ArticleId IdType="doi">10.3389/fphys.2018.00016</ArticleId></ArticleIdList><ReferenceList><Reference><Citation>Bers D. 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<PubmedBookArticle><BookDocument><PMID Version="1">20301308</PMID><ArticleIdList><ArticleId IdType="bookaccession">NBK1129</ArticleId></ArticleIdList><Book><Publisher><PublisherName>University of Washington, Seattle</PublisherName><PublisherLocation>Seattle (WA)</PublisherLocation></Publisher><BookTitle book="gene">GeneReviews<sup>®</sup></BookTitle><PubDate><Year>1993</Year></PubDate><BeginningDate><Year>1993</Year></BeginningDate><EndingDate><Year>2023</Year></EndingDate><AuthorList Type="editors" CompleteYN="Y"><Author ValidYN="Y"><LastName>Adam</LastName><ForeName>Margaret P</ForeName><Initials>MP</Initials></Author><Author ValidYN="Y"><LastName>Mirzaa</LastName><ForeName>Ghayda M</ForeName><Initials>GM</Initials></Author><Author ValidYN="Y"><LastName>Pagon</LastName><ForeName>Roberta A</ForeName><Initials>RA</Initials></Author><Author ValidYN="Y"><LastName>Wallace</LastName><ForeName>Stephanie E</ForeName><Initials>SE</Initials></Author><Author ValidYN="Y"><LastName>Bean</LastName><ForeName>Lora JH</ForeName><Initials>LJH</Initials></Author><Author ValidYN="Y"><LastName>Gripp</LastName><ForeName>Karen W</ForeName><Initials>KW</Initials></Author><Author ValidYN="Y"><LastName>Amemiya</LastName><ForeName>Anne</ForeName><Initials>A</Initials></Author></AuthorList><Medium>Internet</Medium></Book><ArticleTitle book="gene" part="rws">Long QT Syndrome</ArticleTitle><Language>eng</Language><AuthorList Type="authors" CompleteYN="Y"><Author ValidYN="Y"><LastName>Alders</LastName><ForeName>Mariëlle</ForeName><Initials>M</Initials><AffiliationInfo><Affiliation>Department of Clinical Genetics Academic Medical Center University of Amsterdam Amsterdam, The Netherlands</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Bikker</LastName><ForeName>Hennie</ForeName><Initials>H</Initials><AffiliationInfo><Affiliation>Department of Clinical Genetics Academic Medical Center University of Amsterdam Amsterdam, The Netherlands</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Christiaans</LastName><ForeName>Imke</ForeName><Initials>I</Initials><AffiliationInfo><Affiliation>Department of Clinical Genetics Academic Medical Center University of Amsterdam Amsterdam, The Netherlands</Affiliation></AffiliationInfo></Author></AuthorList><PublicationType UI="D016454">Review</PublicationType><Abstract><AbstractText Label="CLINICAL CHARACTERISTICS">Long QT syndrome (LQTS) is a cardiac electrophysiologic disorder, characterized by QT prolongation and T-wave abnormalities on the EKG that are associated with tachyarrhythmias, typically the ventricular tachycardia <i>torsade de pointes</i> (TdP). TdP is usually self-terminating, thus causing a syncopal event, the most common symptom in individuals with LQTS. Such cardiac events typically occur during exercise and emotional stress, less frequently during sleep, and usually without warning. In some instances, TdP degenerates to ventricular fibrillation and causes aborted cardiac arrest (if the individual is defibrillated) or sudden death. Approximately 50% of untreated individuals with a pathogenic variant in one of the genes associated with LQTS have symptoms, usually one to a few syncopal events. While cardiac events may occur from infancy through middle age, they are most common from the preteen years through the 20s. Some types of LQTS are associated with a phenotype extending beyond cardiac arrhythmia. In addition to the prolonged QT interval, associations include muscle weakness and facial dysmorphism in Andersen-Tawil syndrome (LQTS type 7); hand/foot, facial, and neurodevelopmental features in Timothy syndrome (LQTS type 8); and profound sensorineural hearing loss in Jervell and Lange-Nielson syndrome.<AbstractText Label="DIAGNOSIS/TESTING">Diagnosis of LQTS is established by prolongation of the QTc interval in the absence of specific conditions known to lengthen it (for example, QT-prolonging drugs) and/or by molecular genetic testing that identifies a diagnostic change (or changes) in one or more of the 15 genes known to be associated with LQTS – of which <i>KCNH2</i> (LQT2), <i>KCNQ1</i> (locus name LQT1), and <i>SCN5A</i> (LQT3) are the most common. Approximately 20% of families meeting clinical diagnostic criteria for LQTS do not have detectable pathogenic variants in a known gene. LQTS associated with biallelic pathogenic variants or heterozygosity for pathogenic variants in two different genes (i.e., digenic pathogenic variants) is generally associated with a more severe phenotype with longer QTc interval.<AbstractText Label="MANAGEMENT"><i>Treatment of manifestations:</i> Beta blocker medication is the primary treatment for LQTS; possible implantable cardioverter-defibrillators (ICD) and/or left cardiac sympathetic denervation (LCSD) for those with beta-blocker-resistant symptoms, inability to take beta blockers, and/or history of cardiac arrest. Sodium channel blockers can be useful as additional pharmacologic therapy for patients with a QTc interval >500 ms. <i>Prevention of primary manifestations:</i> Beta blockers are clinically indicated in all asymptomatic individuals meeting diagnostic criteria, including those who have a pathogenic variant on molecular testing and a normal QTc interval. In general, ICD implantation is not indicated for individuals with LQTS who are asymptomatic and who have not been tried on beta blocker therapy. Prophylactic ICD therapy can be considered for individuals with LQTS who are asymptomatic but suspected to be at very high risk (e.g., those with ≥2 pathogenic variants on molecular testing). <i>Surveillance:</i> Regular assessment of beta blocker dose for efficacy and adverse effects in all individuals with LQTS, especially children during rapid growth; regular periodic evaluations of ICDs for inappropriate shocks and pocket or lead complications. <i>Agents/circumstances to avoid:</i> Drugs that cause further prolongation of the QT interval or provoke <i>torsade de pointes</i>; competitive sports / activities associated with intense physical activity and/or emotional stress for most individuals. <i>Evaluation of relatives at risk:</i> Presymptomatic diagnosis and treatment is warranted in relatives at risk to prevent syncope and sudden death. <i>Other:</i> For some individuals, availability of automatic external defibrillators at home, at school, and in play areas.<AbstractText Label="GENETIC COUNSELING">LQTS is typically inherited in an autosomal dominant manner. An exception is LQTS associated with sensorineural deafness (known as Jervell and Lange-Nielsen syndrome), which is inherited in an autosomal recessive manner. Most individuals diagnosed with LQTS have an affected parent. The proportion of LQTS caused by a <i>de novo</i> pathogenic variant is small. Each child of an individual with autosomal dominant LQTS has a 50% risk of inheriting the pathogenic variant. Penetrance of the disorder may vary. Prenatal testing for a pregnancy at increased risk and preimplantation genetic testing are possible once the pathogenic variant(s) have been identified in the family. |
19,684 | Hypertensive crisis during catheter ablation of atrial fibrillation in a patient with undiagnosed pheochromocytoma: a case report. | Pheochromocytoma is an unusual cause of hypertension accounting for 0.1% of cases. As the development of atrial fibrillation (AF) is tightly associated with hypertension, patients with pheochromocytoma are at higher risk for AF.</AbstractText>A 72-year-old woman with undiagnosed pheochromocytoma underwent catheter ablation of drug-resistant AF. Procedure-related external factors, such as prescription of a beta blocker without the preventive administration of an alpha blocker, use of contrast medium, administration of anaesthetics, and emotional and pain-related stress, caused a hypertensive crisis with acute left ventricular dysfunction during ablation procedure. After surgical resection of the adrenal tumour, sinus rhythm was maintained without antiarrhythmic drugs.</AbstractText>Because hypertensive crisis can lead to life-threatening organ damage, electrophysiologists seeing patients with AF should always consider pheochromocytoma as a mechanism of hypertension and AF before proceeding to catheter ablation of the AF.</AbstractText> |
19,685 | Predicting arrhythmic risk in arrhythmogenic right ventricular cardiomyopathy: A systematic review and meta-analysis. | While many studies evaluate predictors of ventricular arrhythmias in arrhythmogenic right ventricular cardiomyopathy (ARVC), a systematic review consolidating this evidence is currently lacking. Therefore, we searched MEDLINE and Embase for studies analyzing predictors of ventricular arrhythmias (sustained ventricular tachycardia/fibrillation (VT/VF), appropriate implantable cardioverter-defibrillator therapy, or sudden cardiac death) in patients with definite ARVC, patients with borderline ARVC, and ARVC-associated mutation carriers. In the case of multiple publications on the same cohort, the study with the largest population was included. This yielded 45 studies with a median cohort size of 70 patients (interquartile range 60 patients) and a median follow-up of 5.0 years (interquartile range 3.3 - 6.7 years). The average proportion of arrhythmic events observed was 10.6%/y in patients with definite ARVC, 10.0%/y in patients with borderline ARVC, and 3.7%/y with mutation carriers. Predictors of ventricular arrhythmias were population dependent: consistently predictive risk factors in patients with definite ARVC were male sex, syncope, T-wave inversion in lead >V<sub>3</sub>, right ventricular dysfunction, and prior (non)sustained VT/VF; in patients with borderline ARVC, 2 additional predictors-inducibility during electrophysiology study and strenuous exercise-were identified; and with mutation carriers, all aforementioned predictors as well as ventricular ectopy, multiple ARVC-related pathogenic mutations, left ventricular dysfunction, and palpitations/presyncope determined arrhythmic risk. Most evidence originated from small observational cohort studies, with a moderate quality of evidence. In conclusion, the average risk of ventricular arrhythmia ranged from 3.7 to 10.6%/y depending on the population with ARVC. Male sex, syncope, T-wave inversion in lead >V<sub>3</sub>, right ventricular dysfunction, and prior (non)sustained VT/VF consistently predict ventricular arrhythmias in all populations with ARVC. |
19,686 | Rhythm profiles and survival after out-of-hospital ventricular fibrillation cardiac arrest. | Treatment: protocols for cardiac arrest rely upon rhythm analyses performed at two-minute intervals, neglecting possible rhythm changes during the intervening period of CPR. Our objective was to describe rhythm profiles (patterns of rhythm transitions during two-minute CPR cycles) following attempted defibrillation and to assess their relationship to survival.</AbstractText>The study included out-of-hospital cardiac arrest cases presenting with ventricular fibrillation from 2011 to 2015. The rhythm sequence was annotated during two-minute CPR cycles after the first and second shocks of each case, and the rhythm profile of each sequence was classified. We calculated absolute survival differences among rhythm profiles with the same rhythm at the two-minute check.</AbstractText>Of 569 rhythm sequences after the first shock, 46% included a rhythm transition. Overall survival was 47%, and survival proportion varied by rhythm at the two-minute check: ventricular fibrillation (46%), organized (58%) and asystole (20%). Survival was similar between profiles which ended with an organized rhythm at the two-minute check. Likewise, survival was similar between profiles with asystole at the two-minute check. However, in patients with ventricular fibrillation at the two-minute check, survival was twice as high in those with a transient organized rhythm (69%) compared to constant ventricular fibrillation (32%) or transient asystole (28%).</AbstractText>Rhythm transitions are common after attempted defibrillation. Among patients with ventricular fibrillation at the subsequent two-minute check, transient organized rhythm during the preceding two-minute CPR cycle was associated with favorable survival, suggesting distinct physiologies that could serve as the basis for different treatment strategies.</AbstractText>Copyright © 2018 Elsevier B.V. All rights reserved.</CopyrightInformation> |
19,687 | Variations in subclinical left ventricular dysfunction, functional capacity, and clinical outcomes in different heart failure aetiologies. | Patients with heart failure (HF) risk factors are described as being in Stage A of this condition (SAHF). Management is directed towards prevention of HF progression, but to date, no evidence has been described to align the intensity of this intervention to HF risk. We sought to what extent SAHF of Type 2 diabetes mellitus (T2DM) and other HF risks showed differences in subclinical left ventricular function, exercise capacity, and prognosis.</AbstractText>We recruited 551 elder asymptomatic SAHF patients (age 71 ± 5 years, 49% men, 290 T2DM) with at least one risk factor from a community-based population with preserved ejection fraction. All underwent a comprehensive echocardiogram including global longitudinal strain (GLS) and a 6 min walk test and were followed for 2 years. The primary endpoints were new-onset HF and all-cause mortality. The T2DM group was associated with reduced 6 min walk test distance (451 ± 111 vs. 493 ± 87 m, P < 0.001), worse diastolic function (E/e' 9.2 ± 2.7 vs. 8.7 ± 2.4, P = 0.028), and impaired GLS (-17.7 ± 2.6% vs. -19.0 ± 2.6%, P < 0.001). Over a median follow-up of 1.6 years, 49 T2DM-SAHF and 27 other-SAHF met the primary endpoint. T2DM-SAHF had significantly worse outcome than other-SAHF (P = 0.021). In Cox models, obesity [hazard ratio (HR) = 2.46; P = 0.007], atrial fibrillation (HR = 2.39; P = 0.028), 6 min walk distance (HR = 0.99; P = 0.034), and GLS (HR = 1.14; P = 0.033) were independently associated with the primary endpoint in T2DM-SAHF, independent of age and glycaemic control.</AbstractText>The T2DM-SAHF has worse subclinical left ventricular function, exercise capacity, and prognosis than other-SAHF. Impaired GLS, atrial fibrillation, exercise capacity, and obesity are associated with a worse prognosis in T2DM-SAHF but not in other-SAHF.</AbstractText>© 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.</CopyrightInformation> |
19,688 | Severe sepsis and cardiac arrhythmias. | Although sepsis is a known risk factor for cardiac arrhythmias, data on incidence and outcomes of atrial and ventricular arrhythmias in severe sepsis is limited. The purpose of this study is to examine the association of severe sepsis with cardiac arrhythmias and their impact on outcome in this patient population.</AbstractText>We used hospital discharge data from the Nationwide Inpatient Sample (NIS) during the year 2012. All patients 18 years or older were included in the study. The International Classification of Diseases-Clinical Modification, 9th revision (ICD-9-CM) code was used to identify patients with discharge diagnosis of severe sepsis, atrial fibrillation (A Fib), atrial flutter (AFL), ventricular fibrillation (VF) arrest and non-ventricular fibrillation (non-VF) arrest. In order to study the association of arrhythmias with severe sepsis, two groups were defined: group a-with severe sepsis was compared to group b-without severe sepsis. Univariate and multivariate logistic regression methods were used to adjust for potential confounding factors and variables associated with cardiac arrhythmias were determined.</AbstractText>A total of 30,712,524 NIS hospital discharges (weighted for national estimate) were included in our study, of which 1,756,965 (5.7%) had severe sepsis. On multivariate analysis, after adjusting for potential confounders, severe sepsis was associated with higher risk of A Fib (OR, 1.23; 95% CI, 1.21-1.24), AFL (OR, 1.34; 95% CI, 1.30-1.40), VF arrest (OR, 2.58; 95% CI, 2.38-2.79) (OR, 3.31; 95% CI, 3.07-3.57) and non-VF arrest (OR, 4.91; 95% CI, 4.74-5.07). In the severe sepsis group, cardiac arrhythmia was associated with higher in-hospital mortality (OR, 1.41; 95% CI, 1.37-1.45), length of stay (LOS) >75% quartile (OR, 1.50; 95% CI, 1.46-1.53) and total hospital charges >75% quartile (OR, 1.37; 95% CI, 1.34-1.41). Advanced age, male sex, ischemic heart disease, diabetes mellitus (DM), congestive heart failure (CHF), valvular heart disease, respiratory failure, mechanical ventilation and use of vasopressors were independently associated with cardiac arrhythmias.</AbstractText>Patients with severe sepsis are at high risk of atrial and life threatening ventricular arrhythmias. Despite adjustment for potential confounding factors, patients hospitalized with severe sepsis carry a significantly higher risk for cardiac arrest and increased mortality.</AbstractText> |
19,689 | Stress-induced thrombus: prevalence of thromboembolic events and the role of anticoagulation in Takotsubo cardiomyopathy. | Takotsubo cardiomyopathy (TCM), also known as stress-induced cardiomyopathy has a favorable prognosis with expected recovery in weeks. Left ventricular (LV) thrombus is a known complication of TCM, which can lead to embolization and potentially a stroke. The prevalence of LV thrombus and the role of anticoagulation have yet to be fully defined in this condition.</AbstractText>We performed a search of published literature through PubMed and Scopus, which identified 282 patients with TCM in whom the incidence of LV thrombus and/or thromboembolic event was reported. In order to contrast this to the current anticoagulation strategy of atrial fibrillation, the occurrence of LV thrombus was compared to the adjusted stroke rate using the CHADS2 score.</AbstractText>Of the 282 patients identified through a literature search, 26 (9.2%) were noted to have a thromboembolic event in the setting of TCM. The incidence of thromboembolic event ranged from 5.3% to as high as 14.3%. When compared to the CH2sDS2-VASc score, the average incidence of LV thrombus in our study equated to a score between 4 and 5.</AbstractText>While the occurrence of LV thrombus in TCM is variable among studies, the average incidence remains relatively high. Thus, making LV thrombus a significant complication of stress-induced cardiomyopathy. Prophylactic anticoagulation until recovery may have a role in reducing the rate of LV thrombus. Further studies will be needed to determine the rate of embolization and utility of anticoagulation in TCM.</AbstractText> |
19,690 | Left Atrial Appendage Exclusion Using the AtriClip Device: A Case Series. | Atrial fibrillation (AF) affects 1.5-2% of the population and is associated with a five-fold increased lifetime risk of stroke [1]. The left atrial appendage (LAA) is the source of embolic strokes in up to 90% of patients with non-valvular AF with clots in the left atrium [2].</AbstractText>We reviewed the clinical notes and echocardiographic findings of 20 patients who underwent open cardiac surgery in which concurrent AtriClip (Atricure Inc, Westchester, OH, USA) device insertion was attempted at our institution from July 2013 to February 2015. This was to examine the safety and efficacy of LAA exclusion with clip devices during open cardiac surgery. Indications for LAA exclusion included a history or suspicion of atrial arrhythmia, left ventricular dilatation, or a history of transient ischaemic attacks.</AbstractText>All 20 of the 20 participants had successful placement of the clip device (100% success rate). There were no adverse events related to the device and no perioperative mortality. There were three late deaths due to chronic obstructive pulmonary disease (COPD), leukaemia, and refractory congestive cardiac failure. No late device related complications were found on follow-up imaging in the remaining patients.</AbstractText>The results of our study demonstrate the LAA exclusion during open cardiac surgery with the AtriClip device is safe, has a 100% success rate, and appears to be stable over time.</AbstractText>Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.</CopyrightInformation> |
19,691 | [Effects of mild hypothermia on β-adrenergic signaling pathway in a cardiac arrest swine model]. | To observe the effect of mild hypothermia on myocardial β-adrenergic receptor (β-AR) signal pathway after cardiopulmonary resuscitation (CPR) in pigs with cardiac arrest (CA) and explore the mechanism of myocardial protection.</AbstractText>Healthy male Landraces were collected for reproducing the CA-CPR model (after 8-minute untreated ventricular fibrillation, CPR was implemented). The animals were divided into two groups according to random number table (n = 8). In the mild hypothermia group, the blood temperature of the animals was induced to 33 centigrade and maintained for 6 hours within 20 minutes after return of spontaneous circulation (ROSC) by using a hypothermia therapeutic apparatus. In the control group, the body temperature of the animals was maintained at (38.0±0.5)centigrade with cold and warm blankets. The heart rate (HR), mean arterial pressure (MAP), the maximum rate of increase or decrease in left rentricular pressure (+dp/dt max) were measured during the course of the experiment. The cardiac output (CO) was measured by heat dilution methods before CA (baseline), and 0.5, 1, 3, 6 hours after ROSC respectively, the venous blood was collected to detect the concentration of cTnI. Left ventricular ejection fraction (LVEF) was measured with cardiac ultrasound before CA and 6 hours after ROSC. Animals were sacrificed at 6 hours after ROSC and the myocardial tissue was harvested quickly, the mRNA expression of β1-AR in myocardium was detected by reverse transcription-polymerase chain reaction (RT-PCR), the contents of adenylate cyclase (AC) and cyclic adenosine monophosphate (cAMP) were detected by enzyme linked immunosorbent assay (ELISA), the protein content of G protein-coupled receptor kinase 2 (GRK2) was detected by Western Blot.</AbstractText>After successful resuscitation, the HR of both groups were significantly higher than the baseline values, CO, ±dp/dt max were significantly decreased, MAP were not significantly changed, serum cTnI levels were significantly increased. Compared with the control group, HR at 0.5, 1, 3 hours after ROSC were significantly decreased in mild hypothermia group (bpm: 142.80±12.83 vs. 176.88±15.14, 115.80±11.48 vs. 147.88±18.53, 112.60±7.40 vs. 138.50±12.02, all P < 0.01), CO was significantly increased at 1 hours and 3 hours after ROSC (L/min: 3.97±0.40 vs. 3.02±0.32, 4.00±0.11 vs. 3.11±0.59, both P < 0.01), +dp/dt max at 3 hours and 6 hours was also significantly increased after ROSC [+dp/dt max (mmHg/s): 3 402.5±612.7 vs. 2 130.0±450.6, 3 857.5±510.4 vs. 2 562.5±633.9; -dp/dt max (mmHg/s): 2 935.0±753.2 vs. 1 732.5±513.6, 3 520.0±563.6 vs. 2 510.0±554.3, all P < 0.05], the cTnI was significantly decreased at 3 hours and 6 hours afher ROSC (μg/L: 1.39±0.40 vs. 3.24±0.78, 1.46±0.35 vs. 3.78±0.93, both P < 0.01). The left at 6 hours after ROSC in both groups was decreased as compared with that before CA. The LVEF in the mild hypothermia group was higher than that in the control group (0.52±0.04 vs. 0.40±0.05, P < 0.05). The mRNA expression of β1</sub>-AR, and concentrations of AC and cAMP in hypothermia group were significantly higher than those in control group [β1</sub>-AR mRNA (2-ΔΔCT</sup>): 1.18±0.39 vs. 0.55±0.17, AC (ng/L): 197.0±10.5 vs. 162.0±6.3, cAMP (nmol/L): 1 310.58±48.82 vs. 891.25±64.95, all P < 0.05], GRK2 was lower than that in the control group (GRK2/GAPDH: 0.45±0.05 vs. 0.80±0.08, P < 0.05).</AbstractText>Mild hypothermia can reduce the degree of cardiac function injury after CPR, and its mechanism may be related to the reduction of impaired myocardial β-AR signaling after CPR.</AbstractText> |
19,692 | Electrocardiographic parameters effectively predict ventricular tachycardia/fibrillation in acute phase and abnormal cardiac function in chronic phase of ST-segment elevation myocardial infarction. | Abnormal cardiac repolarization is closely associated with ventricular tachycardia/ventricular fibrillation (VT/VF). Myocardial ischemia and infarction aggravate cardiac repolarization dispersion, and VT/VF could be lethal in the early stage of ST-segment elevation myocardial infarction (STEMI). Unfortunately, VT/VF cannot be effectively predicted in current clinical practice. The present study aimed to assess electrocardiographic parameters of the sinus rhythmic complex in relation to cardiac repolarization, e.g., QT interval and T-peak to T-end interval (TpTe), to independently predict VT/VF in acute STEMI. Additionally, we hypothesized that QT and TpTe of PVC would be also valuable to predict VT/VF in STEMI.</AbstractText>A total of 198 cases diagnosed as STEMI with PVC on admission by electrography were included. During hospitalization, VT/VF values were recorded. Logistic analysis was performed between patients with and without VT/VF to validate independent electrocardiographic predictors. QTcPVC</sub> interval > 520 ms (OR = 3.2; P = 0.027), TpTe interval > 100 ms (OR = 3.1; P = 0.04), TpTePVC</sub>  > 101 ms (OR = 3.6; P = 0.029), TpTe/QT > 0.258 (OR = 5.7; P = 0.003), and TpTe/QTPVC</sub>  > 0.253 (OR = 3; P = 0.048). However, QRS duration, QTc interval, coupling interval, and QRSPVC</sub> duration did not predict VT/VF. Besides, QRSPVC</sub> duration >140 ms (OR = 2.6; P = 0.001) independently predicted LVEF decrease after 1 year or more.</AbstractText>QTcPVC</sub> interval, TpTe interval, TpTePVC</sub> interval, TpTe/QT ratio, and TpTe/QTPVC</sub> ratio are risk factors for ECG independent from other confounding factors in predicting VT/VF in the acute phase of STEMI. In addition, PVC characteristics as risk factors for VT/VF in acute phase and LVEF decrease in chronic phase were firstly reported.</AbstractText>© 2018 Wiley Periodicals, Inc.</CopyrightInformation> |
19,693 | Implantable loop recorders in patients with unexplained syncope: Clinical predictors of pacemaker implantation. | Implantable loop recorders (ILR) are a valuable tool for the investigation of unexplainedsyncopal episodes. The aim of this retrospective single center study was to identify predictive factors for pacemaker implantation in patients with unexplained syncope who underwent ILR insertion.</AbstractText>One hundred six patients were retrospectively analyzed (mean age 59.1 years; 47.2% male) with unexplained syncope and negative conventional testing who underwent ILR implantation. The pri- mary study endpoint was detection of symptomatic or asymptomatic bradycardia requiring pacemaker implantation.</AbstractText>The average follow-up period after ILR implantation was 20 ± 15 months. Pacemaker im- plantation according to current guidelines was necessary in 22 (20.8%) patients, mean duration until index bradycardia was 81 ± 88 (2-350) days. Ten (45.5%) patients received a pacemaker due to sinus arrest, 7 (31.8%) patients due to third-degree atrioventricular block, 2 (9.1%) patients due to second- degree atrioventricular block and 1 (4.5%) patient due to atrial fibrillation with a slow ventricular rate. Three factors remained significant in multivariate analysis: obesity, which defined by a body mass index above 30 kg/m2 (OR: 7.39, p = 0.014), a right bundle branch block (OR: 9.40, p = 0.023) and chronic renal failure as defined by a glomerular filtration rate of less than 60 mL/min (OR: 6.42, p = 0.035).</AbstractText>Bradycardia is a frequent finding in patients undergoing ILR implantation due to un- explained syncope. Obesity, right bundle branch block and chronic renal failure are independent clinical predictors of pacemaker implantation.</AbstractText> |
19,694 | Warfarin accelerated vascular calcification and worsened cardiac dysfunction in remnant kidney mice. | Vascular calcification is highly prevalent in end-stage renal disease (ESRD) and is a significant risk factor for future cardiovascular events and death. Warfarin use results in dysfunction of matrix Gla protein, an inhibitor of vascular calcification. However, the effect of warfarin on vascular calcification in patients with ESRD is still not well characterized. Thus we investigated whether arterial calcification can be accelerated by warfarin treatment both in vitro and in vivo using a mouse remnant kidney model.</AbstractText>Human aortic smooth muscle cells (HASMC) were cultured in medium supplemented with warfarin and phosphate to investigate the potential role of this drug in osteoblast transdifferentiation. For in vivo study, adult male C57BL/6 mice underwent 5/6 nephrectomy were treated with active vitamin D3 plus warfarin to determine the extent of vascular calcification and parameters of cardiovascular function.</AbstractText>We found that the expressions of Runx2 and osteocalcin in HASMC were markedly enhanced in the culture medium containing warfarin and high phosphate concentration. Warfarin induced calcification of cultured HASMC in the presence of high phosphate levels, and this effect is inhibited by vitamin K2. Severe aortic calcification and reduced left ventricular ejection fractions were also noted in 5/6 nephrectomy mice treated with warfarin and active vitamin D3.</AbstractText>Warfarin treatment contributes to the accelerated vascular calcification in animal models of advanced chronic kidney disease. Clinicians should therefore be aware of the profound risk of warfarin use on vascular calcification and cardiac dysfunction in patients with ESRD and atrial fibrillation.</AbstractText>Copyright © 2018. Published by Elsevier Taiwan LLC.</CopyrightInformation> |
19,695 | Emergency medicine considerations in atrial fibrillation. | Atrial fibrillation (AF) is an abnormal heart rhythm which may lead to stroke, heart failure, and death. Emergency physicians play a role in diagnosing AF, managing symptoms, and lessening complications from this dysrhythmia.</AbstractText>This review evaluates recent literature and addresses ED considerations in the management of AF.</AbstractText>Emergency physicians should first assess patient clinical stability and evaluate and treat reversible causes. Immediate cardioversion is indicated in the hemodynamically unstable patient. The American Heart Association/American College of Cardiology, the European Society of Cardiology, and the Canadian Cardiovascular Society provide recommendations for management of AF. If hemodynamically stable, rate or rhythm control are options for management of AF. Physicians may opt for rate control with medications, with beta blockers and calcium channel blockers the predominant medications utilized in the ED. Patients with intact left ventricular function should be rate controlled to <110 beats per minute. Rhythm control is an option for patients who possess longer life expectancy and those with AF onset <48 h before presentation, anticoagulated for 3-4 weeks, or with transesophageal echocardiography demonstrating no intracardiac thrombus. Direct oral anticoagulants are a safe and reliable option for anticoagulation. Clinical judgment regarding disposition is recommended, but literature supports discharging stable patients who do not have certain comorbidities.</AbstractText>Proper diagnosis and treatment of AF is essential to reduce complications. Treatment and overall management of AF include rate or rhythm control, cardioversion, anticoagulation, and admission versus discharge. This review discusses ED considerations regarding AF management.</AbstractText>Published by Elsevier Inc.</CopyrightInformation> |
19,696 | Primary outcomes of the Monitoring in Dialysis Study indicate that clinically significant arrhythmias are common in hemodialysis patients and related to dialytic cycle. | Sudden death is one of the more frequent causes of death for hemodialysis patients, but the underlying mechanisms, contribution of arrhythmia, and associations with serum chemistries or the dialysis procedure are incompletely understood. To study this, implantable loop recorders were utilized for continuous cardiac rhythm monitoring to detect clinically significant arrhythmias including sustained ventricular tachycardia, bradycardia, asystole, or symptomatic arrhythmias in hemodialysis patients over six months. Serum chemistries were tested pre- and post-dialysis at least weekly. Dialysis procedure data were collected at every session. Associations with clinically significant arrhythmias were assessed using negative binomial regression modeling. Sixty-six patients were implanted and 1678 events were recorded in 44 patients. The majority were bradycardias (1461), with 14 episodes of asystole and only one of sustained ventricular tachycardia. Atrial fibrillation, although not defined as clinically significant arrhythmias, was detected in 41% of patients. With thrice-weekly dialysis, the rate was highest during the first dialysis session of the week and was increased during the last 12 hours of each inter-dialytic interval, particularly the long interval. Among serum and dialytic parameters, only higher pre-dialysis serum sodium and dialysate calcium over 2.5 mEq/L were independently associated with clinically significant arrhythmias. Thus, clinically significant arrhythmias are common in hemodialysis patients, and bradycardia and asystole rather than ventricular tachycardia may be key causes of sudden death in hemodialysis patients. Associations with the temporal pattern of dialysis suggest that modification of current dialysis practices could reduce the incidence of sudden death. |
19,697 | Mutation in KCNE1 associated to early repolarization syndrome by modulation of slowly activating delayed rectifier K<sup>+</sup> current. | Recent studies have revealed that mutation in KCNE1, β-subunits of cardiac potassium channel, involved in ventricular fibrillation. Whereas its role in early repolarization syndrome (ERS) is less well understood.</AbstractText>To study whether mutant in KCNE1 is associated with ERS and explore the possible underlying molecular mechanisms.</AbstractText>Whole genome from four unrelated families with ERS was amplified and sequenced. Wild-type (WT) KCNE1 and/or KCNE1-S38G (S38G) were expressed in HEK293 cells with KCNQ1. Functional studies included whole-cell patch-clamp, western blot and immunofluorescence were performed to reveal the possible underlying mechanisms.</AbstractText>The co-expression of KCNE1-S38G and KCNQ1 decreased tail current density of IKs</sub> but had little effect in modulation channel kinetics of IKs</sub>. Compared with KCNE1-WT, the expression and membrane location of KCNE1-S38G decreased. Co-expression of KCNE1-WT and KCNE1-S38G partially rescued the function of IKs</sub> channel.</AbstractText>The S38G mutation induced a loss-of-function of IKs</sub> due to decreasing of KCNE1 protein expression and defecting in KCNE1 protein membrane trafficking. Our findings suggested that KCNE1 may be one of the possible modulatory genes associated to ERS.</AbstractText>Copyright © 2018 Elsevier Inc. All rights reserved.</CopyrightInformation> |
19,698 | A comparative brief on conducted electrical weapon safety. | The variety and high number of published research articles on conducted electrical weapons (CEW) provides a detailed, yet in some parts inconclusive overview of medical aspects of CEW. Due to different research approaches and the use of dissimilar test subjects, an assessment of possible health risks of CEW is limited. The present work provides a brief on CEW safety based on currently available animal, computer and human research data. Using the medical database PubMed, articles published on this topic are critically evaluated and compared with each other. Special focuses are the differences and similarities of human and animal research as well as computer simulation programs. The authors explain why some studies are more reliable than others and give their expert opinion on the safety of CEW. The body of data that have been reviewed provides reasonable support for the safety of CEW. |
19,699 | Cardiac fibroblasts : Active players in (atrial) electrophysiology? | Fibrotic areas in cardiac muscle-be it in ventricular or atrial tissue-are considered as obstacles for conduction of the excitatory wave and can therefore facilitate re-entry, which may contribute to the sustenance of cardiac arrhythmias. Persistence of one of the most frequent arrhythmias, atrial fibrillation (AF), is accompanied by enhanced atrial fibrosis. Any kind of myocardial perturbation, whether via mechanical stress or ischemic damage, inflammation, or irregular and high-frequency electrical activity, activates fibroblasts. This leads to the secretion of paracrine factors and extracellular matrix proteins, especially collagen, and to the differentiation of fibroblasts into myofibroblasts. Excessive collagen production is the hallmark of fibrosis and impairs regular impulse propagation. In addition, direct electrical coupling between cardiomyocytes and nonmyocytes, such as fibroblasts and macrophages, via gap junctions affects conduction. Although fibroblasts are not electrically excitable, they express functional ion channels, in particular K<sup>+</sup> channels and mechanosensitive channels, some of which could be involved in tissue remodeling. Here, we briefly review these aspects with special reference to AF. |
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