Unnamed: 0 int64 0 2.34M | titles stringlengths 5 21.5M | abst stringlengths 1 21.5M |
|---|---|---|
21,000 | Preventive effect of renin-angiotensin system inhibitors on new-onset atrial fibrillation in hypertensive patients: a propensity score matching analysis. | It is still controversial whether treatment with renin-angiotensin system (RAS) inhibitors reduces the risk of incident atrial fibrillation (AF). This longitudinal observational study was performed to investigate the confounder-independent effects of RAS inhibitors on new-onset AF in hypertensive patients. Among 1263 consecutive hypertensive patients who underwent echocardiography, 964 eligible patients (mean age, 63 years) were enrolled as the study population. Forty-nine patients developed new-onset AF during the follow-up period (mean: 4.6 years). Kaplan-Meier analysis showed that the cumulative AF event rate was lower in patients receiving RAS inhibitors than in patients without these drugs, but the difference between these two groups was not significant (P=0.057). Since the use of RAS inhibitors was influenced by concomitant diabetes, chronic kidney disease and left ventricular hypertrophy, propensity score matching (1:1) was employed to minimize the influence of selection bias for RAS inhibitors. Clinical and echocardiographic parameters showed no significant differences between the propensity score-matched groups with and without RAS inhibitor therapy (both n=326), but the cumulative AF event rate was significantly lower in the group receiving RAS inhibitors (P=0.013). Univariate and multivariate Cox regression analyses also revealed that RAS inhibitor therapy was associated with a significantly lower risk of new-onset AF during the follow-up period. In conclusion, this propensity score matching study demonstrated that the incidence of new-onset AF was lower in hypertensive patients receiving RAS inhibitor therapy. |
21,001 | Comparison of Outcomes of Atrial Fibrillation in Patients With Reduced Versus Preserved Left Ventricular Ejection Fraction. | Patients with newly diagnosed atrial fibrillation (AF) and a rapid ventricular response may present with a reduced left ventricular ejection fraction (LVEF). We compared long-term outcomes of these patients with those with preserved LVEF. This retrospective cohort study included 385 consecutive adults with newly diagnosed AF with rapid ventricular response, presenting to a single medical center from January 2006 to August 2014. Patients with a history of coronary artery disease or known cardiomyopathy were excluded. Patients were divided into 2 groups: those with an LVEF ≤55% (n = 147) (REF) and those with an LVEF >55% (n = 238) (PEF). Echocardiographic parameters, all-cause mortality, cardiovascular mortality, and stroke rates were compared between both groups at baseline and a minimum of 1-year follow-up. The mean age of patients was 68 ± 1.1 in REF versus 60 ± 7.4 in PEF (p = 0.39). There were no significant differences in baseline co-morbidities between both groups. The mean LVEF during the index admission was 47.7 ± 0.8% in REF versus 65.5 ± 0.3% in PEF. The average duration of follow-up was 2.8 years. Patients with REF had higher all-cause mortality (32.7% REF vs 20.6% PEF, odds ratio 2.17, p = 0.008). Patients with REF had higher rates of subsequent clinic or ER visits for AF with a rapid ventricular response (32% REF vs 22.7% PEF, p = 0.044). The incidence of stroke was similar between both groups (17% REF vs 18.9% PEF, p = 0.639). Of the patients with REF, 64% had subsequent EF recovery and had similar outcomes compared with patients with PEF. Baseline LV end-diastolic diameter predicted all-cause mortality (odds ratio 1.14, p = 0.003) in the REF group. None of the echocardiographic parameters predicted EF recovery. In conclusion, in patients with new AF with rapid ventricular response, REF was associated with higher long-term all-cause mortality. Those with subsequent LVEF recovery after medical therapy appear to have a similar prognosis compared with those with initial PEF. |
21,002 | Bachmann's Bundle Pacing not Only Improves Interatrial Conduction but Also Reduces the Need for Ventricular Pacing. | Patients treated for sick sinus syndrome may have interatrial conduction disorder leading to atrial fibrillation.</AbstractText>This study was aimed to assess the influence of the atrial pacing site on interatrial and atrioventricular conduction as well as the percentage of ventricular pacing in patients with sick sinus syndrome implanted with atrioventricular pacemaker.</AbstractText>The study population: 96 patients (58 females, 38 males) aged 74.1 ± 11.8 years were divided in two groups: Group 1 (n = 44) with right atrial appendage pacing and group 2 (n = 52) with Bachmann's area pacing. We assessed the differences in atrioventricular conduction in sinus rhythm and atrial 60 and 90 bpm pacing, P-wave duration and percentage of ventricular pacing.</AbstractText>No differences in baseline P-wave duration in sinus rhythm between the groups (102.4 ± 17 ms vs. 104.1 ± 26 ms, p = ns.) were noted. Atrial pacing 60 bpm resulted in longer P-wave in group 1 vs. group 2 (138.3 ± 21 vs. 106.1 ± 15 ms, p < 0.01). The differences between atrioventricular conduction time during sinus rhythm and atrial pacing at 60 and 90 bpm were significantly longer in patients with right atrial appendage vs. Bachmann's pacing (44.1 ± 17 vs. 9.2 ± 7 ms p < 0.01 and 69.2 ± 31 vs. 21.4 ± 12 ms p < 0.05, respectively). The percentage of ventricular pacing was higher in group 1 (21 vs. 4%, p < 0.01).</AbstractText>Bachmann's bundle pacing decreases interatrial and atrioventricular conduction delay. Moreover, the frequency-dependent atrioventricular conduction lengthening is much less pronounced during Bachmann's bundle pacing. Right atrial appendage pacing in sick sinus syndrome patients promotes a higher percentage of ventricular pacing.</AbstractText> |
21,003 | The prognostic significance of atrial fibrillation in heart failure with preserved ejection function: insights from KaRen, a prospective and multicenter study. | The prognostic value of atrial fibrillation (AF) in heart failure with preserved ejection fraction (HFPEF) remains controversial. We sought to study the prognostic value of AF in a prospective cohort and to characterize the HFPEF patients with AF. KaRen was a prospective, multicenter, international, observational study intended to characterize HFPEF; 538 patients presenting with an acute decompensated cardiac failure and a left ventricular EF > 45% were included. EKG and echocardiogram performed 4-8 week following the index hospitalization were analyzed in core centers. Clinical and echocardiographic characteristics of patients in sinus rhythm vs. with documented AF at enrolment (decompensated HF), upon their 4-8-week visit (in presumed stable clinical condition) and according to patients' cardiac history, were compared. The primary study endpoint was death from any cause or first hospitalization for decompensated heart failure (HF). A total of 413 patients (32% in AF) were analyzed, with a mean follow-up period of 28 months. The patients were primarily elderly individuals (mean age: 76.2 years), with a slight female predominance and a high prevalence of non-cardiovascular comorbidities. The baseline echocardiographic characteristics and the natriuretic peptide levels were indicative of a more severe heart condition among the patients with AF. However, the patients with AF exhibited a similar survival-free interval compared with the patients in sinus rhythm. In this elderly HFPEF population with a high prevalence of non-cardiovascular comorbidities, the presence of AF was not associated with a worse prognosis despite impaired clinical and echocardiographic features.ClinicalTrials.gov: NCT00774709. |
21,004 | Providing an Efficient Algorithm for Finding R Peaks in ECG Signals and Detecting Ventricular Abnormalities With Morphological Features. | Ventricular arrhythmias are one of the most important causes of annual deaths in the world, which may lead to sudden cardiac deaths. Accurate and early diagnosis of ventricular arrhythmias in heart diseases is essential for preventing mortality in cardiac patients. Ventricular activity on the electrocardiogram (ECG) signal is in the interval from the beginning of QRS complex to T wave end. Variations in the ECG signal and its features may indicate heart condition of patients. The first step to extract features of ECG in time domain is finding R peaks. In this paper, a combination of two algorithms of Pan-Tompkins and state logic machine has been used to find R peaks in heart signals for normal sinus signals and ventricular abnormalities. Then, a healthy or sick beat may be realized by comparing the difference between R peaks obtained from two algorithms in each beat. The morphological features of the ECG signal in the range of QRS complex are evaluated. Ventricular tachycardia (VT), ventricular flutter (VFL), ventricular fibrillation (VFI), ventricular escape beat (VEB), and premature ventricular contractions (PVCs) are abnormalities studied in this paper. In the classification step, the support vector machine (SVM) classifier with Gaussian kernel (one in front of everyone) is used. Accuracy percentages of ventricular abnormalities mentioned above and normal sinus rhythm are respectively obtained as 95.8%, 92.8%, 94.5, 98.9%, 91.5%, and 100%. The database of this paper has been taken from normal sinus rhythm and MIT-SCD banks available on Physionet.org. |
21,005 | Innovative Approaches to Arrhythmic Storm: The Growing Role of Interventional Procedures. | Arrhythmic or electrical storm (AES) is a clinical condition characterized by 3 or more sustained ventricular arrhythmia episodes leading to appropriate device therapy in a 24-hour period and is associated with very high mortality. The clinical presentation is dramatic, and the management remains challenging. Although pharmacologic treatment and sedation are still part of the initial treatment, newer approaches that include ablation (endocardial, epicardial, or alternative procedures), sympathetic blockade (pharmacologic or by interventional sympathetic denervation), and mechanical hemodynamic support are used increasingly in this setting. In this article we review the current technologies at our disposal clinically to treat AES. |
21,006 | Ranolazine in treatment of stable angina in woman with atrial fibrillation and intermittent left bundle branch block - a case report. | Stable angina is the most frequent manifestation of ischemic heart disease (IHD) in women as compared to men (65% versus 37%). IHD in women has more favorable clinical course because myocardial infarction develops twice as rare as in men. Coronary angiography of angina patients demonstrates normal coronary arteries more frequently in women than in men. Microvascular angina (MVA) is found to be a rather common form of stable IHD as that particular diagnosis is made later in 20-30% of patients who previously underwent coronary angiography. The disease occurs three times as often in women than in men irrespective of age. Most of these patients are in their perimenopausal age - 45-60 years. The major role in MVA development is considered to be decreased coronary flow reserve resulting from evident endothelial dysfunction of minor coronary arteries. MVA is characterized by great variability of its course and low response to conventional antianginal therapy, particularly in women. In view of this the problem of antianginal drugs which can be used in addition to standard therapy remains to be solved. Ranolazine is a new original antianginal medicine which improves left ventricular diastolic filling by selective inhibition of late Na-flow leading to more effective coronary vessels filling in diastole. The article presents the results of multicenter studies of ranolazine as to its effect on diastolic and systolic functions of the left ventricle, clinical manifestations of angina and heart failure as well as the data on antiarrhythmic action of ranolazine. This article describes the case of successful use of ranolazine as an additional anti-anginal medicine in the 46- year-old female patient diagnosed with microvascular angina. Before taking ranolazine, on the background of conventional treatment of coronary heart disease, the patient developed stable angina and persistent left bundle branch block, atrial fibrillation. After receiving ranolazine, 1000 mg per day for a month, Holter ECG monitoring showed not only significantly reduced number of strokes, the left bundle branch block and atrial fibrillation dissappeared as well. The results indicate a high efficiency of ranolazine as an antianginal, anti-ischemic and anti-arrythmic medicine. |
21,007 | Electrocardiographic left ventricular hypertrophy predicts atrial fibrillation independent of left ventricular mass. | Although left ventricular hypertrophy (LVH) detected by electrocardiography (ECG-LVH) and echocardiography (echo-LVH) independently predict cardiovascular disease events, it is unclear if ECG-LVH and echo-LVH independently predict atrial fibrillation (AF).</AbstractText>This analysis included 4,904 participants (40% male; 85% white) from the Cardiovascular Health Study who were free of baseline AF and major intraventricular conduction delays. ECG-LVH was defined by Minnesota Code Classification from baseline ECG data. Echo-LVH was defined by sex-specific left ventricular mass values >95th sex-specific percentiles. Incident AF events were identified during the annual study ECGs and from hospitalization discharge data. Cox regression was used to compute hazard ratios (HR) and 95% confidence intervals (CI) for the association of ECG-LVH and echo-LVH with incident AF, separately.</AbstractText>ECG-LVH was detected in 224 (4.6%) participants and echo-LVH was present in 231 (4.7%) participants. Over a median follow-up of 11.9 years, a total of 1,430 AF events were detected. In a multivariable Cox model adjusted for age, sex, race, education, income, smoking, systolic blood pressure, diabetes, body mass index, total cholesterol, high-density lipoprotein cholesterol, aspirin, antihypertensive medications, and cardiovascular disease, ECG-LVH (HR = 1.50; 95% CI = 1.18, 1.90) and echo-LVH (HR = 1.39; 95% CI = 1.09, 1.78) were independently associated with AF. When ECG-LVH (HR = 1.47, 95% CI = 1.16, 1.87) and echo-LVH (HR = 1.36, 1.07, 1.75) were included in the same model, both were predictive of incident AF.</AbstractText>The association of ECG-LVH with AF is not dependent on left ventricular mass detected by echocardiography, suggesting that abnormalities in cardiac electrophysiology provide a distinct profile in the prediction of AF.</AbstractText>© 2016 Wiley Periodicals, Inc.</CopyrightInformation> |
21,008 | Autonomic Modulation for the Treatment of Ventricular Arrhythmias: Therapeutic Use of Percutaneous Stellate Ganglion Blocks. | Ventricular tachycardia (VT), ventricular fibrillation (VF), and electrical storm are commonly encountered emergency conditions in cardiac and surgical intensive care units. In most cases, recurrent ventricular arrhythmias or electrical storm are associated with a heightened sympathetic tone. These arrhythmias can be difficult to treat and may be refractory to beta-blockade, antiarrhythmic therapy, sedation, and mechanical hemodynamic support. While monomorphic ventricular tachycardia and PVC-triggered polymorphic ventricular tachycardia may sometimes be amenable to successful ablation, some patients may be too critically ill to make such an approach feasible. We present 2 cases of minimally invasive stellate ganglion blocks for the treatment of electrical storm in patients with advanced heart failure on mechanical life support. These cases are part of a collaborative initiative at our institution to use percutaneous stellate ganglion block as an adjunctive intervention to achieve control of life-threatening ventricular arrhythmias. |
21,009 | Technical Considerations of Giant Right Coronary Artery Aneurysm Exclusion. | Giant coronary artery aneurysms are rare clinical entities. We report the case of a 49-year-old man who presented with dyspnoea and exertional chest pain. Investigations confirmed an aneurysmal right coronary artery measuring 4 cm with a fistulous communication to the right atrium. Following right atriotomy, the fistula was oversewn and the aneurysmal right coronary artery ligated at its origin and at several points along its course. A saphenous vein graft was anastomosed to the posterior descending artery. Persistent ventricular fibrillation occurred upon chest closure, attributed to ischaemia following ligation of the aneurysmal coronary artery. Emergent resternotomy and internal defibrillation were successfully performed. The sternum was stented open to reduce right ventricular strain and closed the following day. The patient made an unremarkable recovery. We here address the technical challenges associated with surgical repair of right coronary aneurysms and the physiology and management of potential complications. |
21,010 | Atrial Fibrillation in Heart Failure With Preserved Ejection Fraction: Association With Exercise Capacity, Left Ventricular Filling Pressures, Natriuretic Peptides, and Left Atrial Volume. | This study sought to study the association of atrial fibrillation (AF) with exercise capacity, left ventricular filling pressure, natriuretic peptides, and left atrial size in heart failure with preserved ejection fraction (HFpEF).</AbstractText>The diagnosis of HFpEF in patients with AF remains a challenge because both contribute to impaired exercise capacity, and increased natriuretic peptides and left atrial volume.</AbstractText>We studied 94 patients with symptomatic heart failure and left ventricular ejection fractions ≥45% using treadmill cardiopulmonary exercise testing and right- and/or left-sided cardiac catheterization with simultaneous echocardiography.</AbstractText>During catheterization, 62 patients were in sinus rhythm, and 32 patients had AF. There were no significant differences in age, sex, body size, comorbidities, or medications between groups; however, patients with AF had lower peak oxygen consumption (VO2</sub>) compared with those with sinus rhythm (10.8 ± 3.1 ml/min/kg vs. 13.5 ± 3.8 ml/min/kg; p = 0.002). Median (25th to 75th percentile) N-terminal pro-B-type natriuretic peptide (NT-proBNP) was higher in AF versus sinus rhythm (1,689; 851 to 2,637 pg/ml vs. 490; 272 to 1,019 pg/ml; p < 0.0001). Left atrial volume index (LAVI) was higher in AF than sinus rhythm (57.8 ± 17.0 ml/m2</sup> vs. 42.5 ± 15.1 ml/m2</sup>; p = 0.001). Invasive hemodynamics showed higher mean pulmonary capillary wedge pressure (PCWP) (19.9 ± 3.7 vs. 15.2 ± 6.8) in AF versus sinus rhythm (all p < 0.001), with a trend toward higher left ventricular end-diastolic pressure (17.7 ± 3.0 mm Hg vs. 15.7 ± 6.9 mm Hg; p = 0.06). After adjusting for clinical covariates and mean PCWP, AF remained associated with reduced peak VO2</sub> increased log NT-proBNP, and enlarged LAVI (all p ≤0.005).</AbstractText>AF is independently associated with greater exertional intolerance, natriuretic peptide elevation, and left atrial remodeling in HFpEF. These data support the application of different thresholds of NT-proBNP and LAVI for the diagnosis of HFpEF in the presence of AF versus the absence of AF.</AbstractText>Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
21,011 | Thorax Percutaneous Approach for Epicardial Ventricular Ablation in a Patient with Electrical Storm. | Subxiphoid puncture is considered the standard approach for epicardial ablation of ventricular arrhythmia, but in some cases this access is impracticable due to the patient's anatomy. We describe the case of a patient with electrical storm and abnormal subdiaphragmatic anatomy that precluded the usual subxiphoid approach. In this patient the pericardial space was gained through a direct thorax puncture at the fifth intercostals space close to the mammary line. The tools and technique utilized in this case were similar to what is usually used for traditional subxiphoid puncture. The thorax percutaneous puncture was successfully carried out without complication. |
21,012 | Histological evidence of inflammatory reaction associated with fibrosis in the atrial and ventricular walls in a case-control study of patients with history of atrial fibrillation. | Chronic inflammation in the atrial myocardium was shown to play an important role in the development of atrial fibrosis in patients with atrial fibrillation (AF). However, it is not clear to what extent atrial inflammatory reaction associated with AF extends on the ventricular myocardium. Our aim was to assess the extent of fibrosis and lymphomononuclear infiltration in human ventricular myocardium and explore its association with AF.</AbstractText>Medical records from consecutive autopsies were checked for presence of AF. Heart specimens from 30 patients died from cardiovascular causes (64 ± 12 years, 17 men) were collected in three equal groups: no AF, paroxysmal AF, and permanent AF. Tissue samples were taken from the Bachmann's bundle, crista terminalis, posterior left atrium, left ventricle and right ventricle free walls and stained with Masson's trichrome for analysis of fibrosis extent. Immunohistochemistry was performed using antibodies against CD3- and CD45-antigens and quantified as number of antigen-positive cells per 1 mm2</sup>. Fibrosis extent, CD3+ and CD45+ cell counts were elevated in AF patients at all sites (P < 0.001 for all). Fibrosis extent demonstrated correlation with both CD3+ and CD45+ cell counts in the right (r = 0.781, P < 0.001 for CD45+ and r = 0.720, P < 0.001 for CD3+) and the left (r = 0.515, P = 0.004 for CD45+ and r = 0.573, P = 0.001 for CD3+) ventricles. Neither fibrosis nor inflammatory cell count showed association with either age or comorbidities.</AbstractText>Histological signs of chronic inflammation affecting ventricular myocardium are strongly associated with AF and demonstrate significant correlation with fibrosis extent that cannot be explained by cardiovascular comorbidities otherwise.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For Permissions, please email: journals.permissions@oup.com.</CopyrightInformation> |
21,013 | Cardiac sympathetic innervation via middle cervical and stellate ganglia and antiarrhythmic mechanism of bilateral stellectomy. | Cardiac sympathetic denervation (CSD) is reported to reduce the burden of ventricular tachyarrhythmias [ventricular tachycardia (VT)/ventricular fibrillation (VF)] in cardiomyopathy patients, but the mechanisms behind this benefit are unknown. In addition, the relative contribution to cardiac innervation of the middle cervical ganglion (MCG), which may contain cardiac neurons and is not removed during this procedure, is unclear. The purpose of this study was to compare sympathetic innervation of the heart via the MCG vs. stellate ganglia, assess effects of bilateral CSD on cardiac function and VT/VF, and determine changes in cardiac sympathetic innervation after CSD to elucidate mechanisms of benefit in 6 normal and 18 infarcted pigs. Electrophysiological and hemodynamic parameters were evaluated at baseline, during bilateral stellate stimulation, and during bilateral MCG stimulation in 6 normal and 12 infarcted animals. Bilateral CSD (removal of bilateral stellates and T<sub>2</sub> ganglia) was then performed and MCG stimulation repeated. In addition, in 18 infarcted animals VT/VF inducibility was assessed before and after CSD. In infarcted hearts, MCG stimulation resulted in greater chronotropic and inotropic response than stellate ganglion stimulation. Bilateral CSD acutely reduced VT/VF inducibility by 50% in infarcted hearts and prolonged global activation recovery interval. CSD mitigated effects of MCG stimulation on dispersion of repolarization and T-peak to T-end interval in infarcted hearts, without causing hemodynamic compromise. These data demonstrate that the MCG provides significant cardiac sympathetic innervation before CSD and adequate sympathetic innervation after CSD, maintaining hemodynamic stability. Bilateral CSD reduces VT/VF inducibility by improving electrical stability in infarcted hearts in the setting of sympathetic activation.<b>NEW & NOTEWORTHY</b> Sympathetic activation in myocardial infarction leads to arrhythmias and worsens heart failure. Bilateral cardiac sympathetic denervation reduces ventricular tachycardia/ventricular fibrillation inducibility and mitigates effects of sympathetic activation on dispersion of repolarization and T-peak to T-end interval in infarcted hearts. Hemodynamic stability is maintained, as innervation via the middle cervical ganglion is not interrupted. |
21,014 | Mid-range Ejection Fraction Does Not Permit Risk Stratification Among Patients Hospitalized for Heart Failure. | European Society of Cardiology heart failure guidelines include a new patient category with mid-range (40%-49%) left ventricular ejection fraction (HFmrEF). HFmrEF patient characteristics and prognosis are poorly defined. The aim of this study was to analyze the HFmrEF category in a cohort of hospitalized heart failure patients (REDINSCOR II Registry).</AbstractText>A prospective observational study was conducted with 1420 patients classified according to ejection fraction as follows: HFrEF, < 40%; HFmrEF, 40%-49%; and HFpEF, ≥ 50%. Baseline patient characteristics were examined, and outcome measures were mortality and readmission for heart failure at 1-, 6-, and 12-month follow-up. Propensity score matching was used to compare the HFmrEF group with the other ejection fraction groups.</AbstractText>Among the study participants, 583 (41%) had HFrEF, 227 (16%) HFmrEF, and 610 (43%) HFpEF. HFmrEF patients had a clinical profile similar to that of HFpEF patients in terms of age, blood pressure, and atrial fibrillation prevalence, but shared with HFrEF patients a higher proportion of male participants and ischemic etiology, and use of class I drugs targeting HFrEF. All other features were intermediate, and comorbidities were similar among the 3 groups. There were no significant differences in all-cause mortality, cause of death, or heart failure readmission. The similar outcomes were confirmed in the propensity score matched cohorts.</AbstractText>The HFmrEF patient group has characteristics between the HFrEF and HFpEF groups, with more similarities to the HFpEF group. No between-group differences were observed in total mortality, cause of death, or heart failure readmission.</AbstractText>Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.</CopyrightInformation> |
21,015 | A Guide to Transseptal Access. | Transseptal access is commonly performed for any procedure that requires access to the left side of the heart such as catheter ablation of atrial fibrillation, left atrial tachycardia, left-sided accessory pathways, ventricular tachycardia, left atrial appendage closure, percutaneous mitral valvuloplasty, and mitral valve repair. To perform this in a safe and effective manner it is important that the operator has a detailed knowledge of the relevant anatomy, the technique required, and the ability to deal with difficult cases and complications. The aim of this article is to provide a detailed description of the anatomy, techniques, potential complications, and difficulties associated with performing this procedure. |
21,016 | Amiodarone Versus Lidocaine for Pediatric Cardiac Arrest Due to Ventricular Arrhythmias: A Systematic Review. | We performed a systematic review as part of the International Liaison Committee on Resuscitation process to create a consensus on science statement regarding amiodarone or lidocaine during pediatric cardiac arrest for the 2015 International Liaison Committee on Resuscitation's Consensus on Science and Treatment Recommendations.</AbstractText>Studies were identified from comprehensive searches in PubMed, Embase, and the Cochrane Library.</AbstractText>Studies eligible for inclusion were randomized controlled and observational studies on the relative clinical effect of amiodarone or lidocaine in cardiac arrest.</AbstractText>Studies addressing the clinical effect of amiodarone versus lidocaine were extracted and reviewed for inclusion and exclusion criteria by the reviewers. Studies were rigorously analyzed thereafter.</AbstractText>We identified three articles addressing lidocaine versus amiodarone in cardiac arrest: 1) a prospective study assessing lidocaine versus amiodarone for refractory ventricular fibrillation in out-of-hospital adults; 2) an observational retrospective cohort study of inpatient pediatric patients with ventricular fibrillation or pulseless ventricular tachycardia who received lidocaine, amiodarone, neither or both; and 3) a prospective study of ventricular tachycardia with a pulse in adults. The first study showed a statistically significant improvement in survival to hospital admission with amiodarone (22.8% vs 12.0%; p = 0.009) and a lack of statistical difference for survival at discharge (p = 0.34). The second article demonstrated 44% return of spontaneous circulation for amiodarone and 64% for lidocaine (odds ratio, 2.02; 1.36-3.03) with no statistical difference for survival at hospital discharge. The third article demonstrated 48.3% arrhythmia termination for amiodarone versus 10.3% for lidocaine (p < 0.05). All were classified as lower quality studies without preference for one agent.</AbstractText>The confidence in effect estimates is so low that International Liaison Committee on Resuscitation felt that a recommendation to use of amiodarone over lidocaine is too speculative; we suggest that amiodarone or lidocaine can be used in the setting of pulseless ventricular tachycardia/ventricular fibrillation in infants and children.</AbstractText> |
21,017 | Intermuscular technique for implantation of the subcutaneous implantable cardioverter defibrillator: long-term performance and complications. | The subcutaneous cardioverter defibrillator was designed to overcome electrode complications of transvenous defibrillation systems. While largely achieved, pocket complications have increased. Subcutaneous implantation of the pulse generator leaves it prone to erosion, extrusion, discomfort, and poor cosmesis.</AbstractText>We use a demonstration electrode and pulse generator with fluoroscopy, prior to prepping and draping, to maximize the left ventricular mass between them. We adapted a submuscular abdominal ICD technique to implant the S-ICD intermuscularly between the anterior surface of serratus anterior and the posterior surface of latissimus dorsi. Surgery in our patients beyond the subcutaneous tissue was bloodless, as muscle layers were carefully separated but not incised, which also protected the long thoracic nerve. Two layers of muscle protect the pulse generator. We have implanted 82 consecutive patients with this technique, taking ∼65 min. All patients were converted with 65 J standard polarity shock during induced arrhythmia conversion testing, with six (7.3%) patients requiring a repositioning of the pulse generator prior to successful conversion. Seven spontaneous episodes of ventricular fibrillation were detected in three (3.6%) patients, all successfully converted back to sinus rhythm. Long-term patient outcomes have been good with low complication rates over the mean ± standard deviation 3.6 ± 1.2 years.</AbstractText>Our intermuscular technique and implant methodology is successful for placement of the subcutaneous defibrillator pulse generator. Our technique leads to an excellent cosmetic result and high levels of patient satisfaction. Rates of first shock conversion during defibrillation testing, inappropriate shocks, and complications during follow-up compare favourably with previous published case series. There were no left arm movement limitations post-operatively.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
21,018 | Early Coronary Reperfusion Facilitates Return of Spontaneous Circulation and Improves Cardiovascular Outcomes After Ischemic Cardiac Arrest and Extracorporeal Resuscitation in Pigs. | Extracorporeal cardiopulmonary resuscitation (ECPR) is widely proposed for the treatment of refractory cardiac arrest. It should be associated with coronary angiography if coronary artery disease is suspected. However, the prioritization of care remains unclear in this situation. Our goal was to determine whether coronary reperfusion should be instituted as soon as possible in such situations in a pig model.</AbstractText>Anesthetized pigs were instrumented and submitted to coronary artery occlusion and ventricular fibrillation. After 5 minutes of untreated cardiac arrest, conventional cardiopulmonary resuscitation (CPR) was started. Fifteen minutes later, ECPR was initiated for a total duration of 240 minutes. Animals randomly underwent either early or late coronary reperfusion at 20 or 120 minutes of ECPR, respectively. This timing was adapted to the kinetic of infarct extension in pigs. Return of spontaneous circulation was determined as organized electrocardiogram rhythm with systolic arterial pressure above 80 mm Hg. During conventional CPR, hemodynamic parameters were not different between groups. Carotid blood flow then increased by 70% after the onset of ECPR in both groups. No animal (0 of 7) elicited return of spontaneous circulation after late reperfusion versus 4 of 7 after early reperfusion (P=0.025). The hemodynamic parameters, such as carotid blood flow, were also improved in early versus late reperfusion groups (113±20 vs 43±17 mL/min after 240 minutes of ECPR, respectively; P=0.030), along with infarct size decrease (71±4% vs 84±2% of the risk zone, respectively; P=0.013).</AbstractText>Early reperfusion improved hemodynamic status and facilitated return of spontaneous circulation in a porcine model of ischemic cardiac arrest treated by ECPR.</AbstractText>© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.</CopyrightInformation> |
21,019 | Rescuing the Late Failing Fontan: Focus on Surgical Treatment of Dysrhythmias. | Patients with a failing Fontan frequently have dysrhythmias. This review will focus on the treatment of those dysrhythmias based on the 140 patients who have had a Fontan conversion with arrhythmia surgery at Ann & Robert H. Lurie Children's Hospital of Chicago (Chicago, IL). Important technical points to be emphasized are the following:• Atrial fibrillation is extremely common in patients with a failing Fontan and strong consideration should be given to a Cox-maze III during any Fontan conversion• Sinus node dysfunction is common post-conversion and all patients should receive a dual-chamber epicardial pacemaker• Careful preoperative imaging with either computed tomographic or magnetic resonance imaging is needed to predict re-entry problems at the time of repeat sternotomy• If the patient has protein-losing enteropathy, ascites, or a right or indeterminate ventricular morphology, strong consideration should be given to heart transplantation rather than a Fontan conversion and arrhythmia surgery. Freedom from cardiac death or transplant for patients undergoing Fontan conversion with arrhythmia surgery is 84% at 10 years. The effects of atrial arrhythmia operations are durable in most patients. There is increasing evidence that earlier referral of patients with an atriopulmonary Fontan for Fontan conversion will improve long-term results. Fontan conversion should be performed at centers with the institutional expertise to care for these complex patients. Note that this is an eroding patient population. The time to act may be now. |
21,020 | TREK-1 (K<sub>2P</sub>2.1) K<sup>+</sup> channels are suppressed in patients with atrial fibrillation and heart failure and provide therapeutic targets for rhythm control. | Atrial fibrillation (AF) is the most common cardiac arrhythmia. Concomitant heart failure (HF) poses a particular therapeutic challenge and is associated with prolonged atrial electrical refractoriness compared with non-failing hearts. We hypothesized that downregulation of atrial repolarizing TREK-1 (K<sub>2P</sub>2.1) K<sup>+</sup> channels contributes to electrical remodeling during AF with HF, and that TREK-1 gene transfer would provide rhythm control via normalization of atrial effective refractory periods in this AF subset. In patients with chronic AF and HF, atrial TREK-1 mRNA levels were reduced by 82% (left atrium) and 81% (right atrium) compared with sinus rhythm (SR) subjects. Human findings were recapitulated in a porcine model of atrial tachypacing-induced AF and reduced left ventricular function. TREK-1 mRNA (-66%) and protein (-61%) was suppressed in AF animals at 14-day follow-up compared with SR controls. Downregulation of repolarizing TREK-1 channels was associated with prolongation of atrial effective refractory periods versus baseline conditions, consistent with prior observations in humans with HF. In a preclinical therapeutic approach, pigs were randomized to either atrial Ad-TREK-1 gene therapy or sham treatment. Gene transfer effectively increased TREK-1 protein levels and attenuated atrial effective refractory period prolongation in the porcine AF model. Ad-TREK-1 increased the SR prevalence to 62% during follow-up in AF animals, compared to 35% in the untreated AF group. In conclusion, TREK-1 downregulation and rhythm control by Ad-TREK-1 transfer suggest mechanistic and potential therapeutic significance of TREK-1 channels in a subgroup of AF patients with HF and prolonged atrial effective refractory periods. Functional correction of ionic remodeling through TREK-1 gene therapy represents a novel paradigm to optimize and specify AF management. |
21,021 | Regional Longitudinal Deformation Improves Prediction of Ventricular Tachyarrhythmias in Patients With Heart Failure With Reduced Ejection Fraction: A MADIT-CRT Substudy (Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy). | Left ventricular dysfunction is a known predictor of ventricular arrhythmias. We hypothesized that measures of regional longitudinal deformation by speckle-tracking echocardiography predict ventricular tachyarrhythmias and provide incremental prognostic information over clinical and conventional echocardiographic characteristics.</AbstractText>We studied 1064 patients enrolled in the MADIT-CRT trial (Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy) with speckle-tracking data available. Peak longitudinal strain was obtained for the septal, lateral, anterior, and inferior myocardial walls at baseline. The end point was the first event of ventricular tachycardia (VT) or fibrillation (VF). During the median follow-up of 2.9 years, 254 (24%) patients developed VT/VF. Patients with VT/VF had significantly lower left ventricular ejection fraction (28.3% versus 29.5%; P<0.001) and longitudinal strain in all myocardial walls compared with patients without VT/VF (anterior-strain, -7.7% versus -8.8%; P<0.001; lateral-strain, -7.3% versus -7.9%; P=0.022; inferior-strain, -8.3% versus -9.9%; P<0.001; septal-strain, -9.1% versus -10.0%; P<0.001). After multivariate adjustment, only anterior and inferior longitudinal strain remained independent predictors of VT/VF (anterior: hazard ratio, 1.08 [1.03-1.13]; P=0.001; inferior: hazard ratio, 1.08 [1.04-1.12]; P<0.001; per 1% absolute decrease for both). When including B-type natriuretic peptide in the model, only a decreasing myocardial function in the inferior myocardial wall predicted VT/VF (hazard ratio, 1.05 [1.00-1.11]; P=0.039). Only strain obtained from the inferior myocardial wall provided incremental prognostic information for VT/VF over clinical and echocardiographic parameters (C statistic 0.71 versus 0.69; P=0.005).</AbstractText>Assessment of regional longitudinal myocardial deformation in the inferior region provided incremental prognostic information over clinical and echocardiographic risk factors in predicting ventricular tachyarrhythmias.</AbstractText>URL: http://www.clinicaltrials.gov. Unique identifier: NCT00180271.</AbstractText>© 2016 American Heart Association, Inc.</CopyrightInformation> |
21,022 | Early increase in serum fatty acid binding protein 4 levels in patients with acute myocardial infarction. | Acute myocardial infarction (AMI) induces marked activation of the sympathetic nervous system. Fatty acid binding protein 4 (FABP4) is not only an intracellular protein, but also a secreted adipokine that contributes to obesity-related metabolic complications. Here, we examined the role of serum FABP4 as a pathophysiological marker in patients with AMI.</AbstractText>We studied 106 patients presenting to the emergency unit with a final diagnosis of AMI, including 12 patients resuscitated from out-of-hospital cardiac arrest (OHCA) caused by ventricular fibrillation. FABP4 levels peaked on admission or just after percutaneous coronary intervention and declined thereafter. Regression analysis revealed no significant correlation between peak FABP4 and peak cardiac troponin T determined by Roche high-sensitive assays (hs-TnT). Notably, FABP4 levels were particularly elevated in AMI patients who were resuscitated from OHCA (median 130.2 ng/mL, interquartile range (IQR) 51.8-243.9 ng/mL) compared with those without OHCA (median 26.1 ng/ml, IQR 17.1-43.4 ng/mL), while hs-TnT levels on admission were not associated with OHCA. Immunohistochemistry of the human heart revealed that FABP4 is abundantly present in adipocytes within myocardial tissue and epicardial adipose tissue. An in vitro study using cultured adipocytes showed that FABP4 is released through a β3-adrenergic receptor (AR)-mediated mechanism.</AbstractText>FABP4 levels were significantly elevated during the early hours after the onset of AMI and were robustly increased in OHCA survivors. Together with the finding that FABP4 is released from adipocytes via β3-AR-mediated lipolysis, our data provide a novel hypothesis that serum FABP4 may represent the adrenergic overdrive that accompanies acute cardiovascular disease, including AMI.</AbstractText> |
21,023 | Atrial fibrillation with high ventricular rate in emergency room: What's the best strategy for treatment? | Atrial fibrillation (AF) is the most common arrhythmia in clinical practice and can lead to significant decline in functional status and quality of life among affected patients. The risk of developing AF increases with age and the presence of structural heart disease. Thus, the attendance of patients with high ventricular response to AF is common, which makes knowledge of its management mandatory. In this context, the choice of heart rate and/or rhythm control therapy is fundamental and complex, with multiple possibilities. Thus, this review aims to assist in the management of these patients, systematizing their care. |
21,024 | Variants of Brugada Syndrome and Early Repolarization Syndrome: An Expanded Concept of J-Wave Syndrome. | The role of J-waves in the pathogenesis of ventricular fibrillation (VF) occurring in structurally normal hearts is important.</AbstractText>We evaluated 127 patients who received an implantable cardioverter-defibrillator (ICD) for Brugada syndrome (BS, n = 53), early repolarization syndrome (ERS, n = 24), and patients with unknown or deferred diagnosis (n = 50). Electrocardiography (ECG), clinical characteristics, and ICD data were analyzed.</AbstractText>J-waves were found in 27/50 patients with VF of unknown/deferred diagnosis. The J-waves were reminiscent of those seen in BS or ERS, and this subgroup of patients was termed variants of ERS and BS (VEB). In 12 VEB patients, the J/ST/T-wave morphology was coved, although amplitudes were <0.2 mV. In 15 patients, noncoved-type J/ST/T-waves were present in the right precordial leads. In the remaining 23 patients, no J-waves were identified. VEB patients exhibited clinical characteristics similar to those of BS and ERS patients. Phenotypic transition and overlap were observed among patients with BS, ERS, and VEB. Twelve patients with BS had background inferolateral ER, while five ERS patients showed prominent right precordial J-waves. Patients with this transient phenotype overlap showed a significantly lower shock-free survival than the rest of the study patients.</AbstractText>VEB patients demonstrate ECG phenotype similar to but distinct from those of BS and ERS. The spectral nature of J-wave morphology/distribution and phenotypic transition/overlap suggest a common pathophysiologic background in patients with VEB, BS, and ERS. Prognostic implication of these ECG variations requires further investigation.</AbstractText>© 2016 Wiley Periodicals, Inc.</CopyrightInformation> |
21,025 | Implantable cardioverter-defibrillator in a patient with dextrocardia situs inversus. | Dextrocardia is a congenital anomaly, which may have coexistent coronary artery disease (CAD), arrhythmias and conventional indications for device therapy. However, the implantation of transvenous leads can be technically challenging and the approach needs to be tailored to the patient's individual anatomy.</AbstractText>A 54-year-old male with dextrocardia situs inversus and ischemic left ventricular dysfunction developed ventricular tachycardia and fibrillation. Therefore, left- sided approach, dual chamber implantable cardioverter-defibrillator (ICD) was applied using a conventional method and standard equipment after complete evaluation of cardiac anatomy and vascular assessment.</AbstractText>Electrical device implantation in patients with dextrocardia is possible after obtaining complete information about anatomy and/or coexisting congenital abnormalities, which helps in obtaining appropriate implantation approach.</AbstractText> |
21,026 | Does therapeutic hypothermia during extracorporeal cardiopulmonary resuscitation preserve cardiac function? | Extracorporeal cardiopulmonary resuscitation (E-CPR) is increasingly used as a rescue method in the management of cardiac arrest and provides the opportunity to rapidly induce therapeutic hypothermia. The survival after a cardiac arrest is related to post-arrest cardiac function, and the application of therapeutic hypothermia post-arrest is hypothesized to improve cardiac outcome. The present animal study compares normothermic and hypothermic E-CPR considering resuscitation success, post-arrest left ventricular function and magnitude of myocardial injury.</AbstractText>After a 15-min untreated ventricular fibrillation, the pigs (n = 20) were randomized to either normothermic (38 °C) or hypothermic (32-33 °C) E-CPR. Defibrillation terminated ventricular fibrillation after 5 min of E-CPR, and extracorporeal support continued for 2 h, followed by warming, weaning and a stabilization period. Magnetic resonance imaging and left ventricle pressure measurements were used to assess left ventricular function pre-arrest and 5 h post-arrest. Myocardial injury was estimated by serum concentrations of cardiac TroponinT and Aspartate transaminase (ASAT).</AbstractText>E-CPR resuscitated all animals and the hypothermic strategy induced therapeutic hypothermia within minutes without impairment of the resuscitation success rate. All animals suffered a severe global systolic left ventricular dysfunction post-arrest with 50-70% reductions in stroke volume, ejection fraction, wall thickening, strain and mitral annular plane systolic excursion. Serum concentrations of cardiac TroponinT and ASAT increased considerably post-arrest. No significant differences were found between the two groups.</AbstractText>Two-hour therapeutic hypothermia during E-CPR offers an equal resuscitation success rate, but does not preserve the post-arrest cardiac function nor reduce the magnitude of myocardial injury, compared to normothermic E-CPR. Trial registration FOTS 4611/13 registered 25 October 2012.</AbstractText> |
21,027 | Mechanisms of IhERG/IKr Modulation by α1-Adrenoceptors in HEK293 Cells and Cardiac Myocytes. | The rapid delayed rectifier K+ current (IKr), carried by the hERG protein, is one of the main repolarising currents in the human heart and a reduction of this current increases the risk of ventricular fibrillation. α1-adrenoceptors (α1-AR) activation reduces IKr but, despite the clear relationship between an increase in the sympathetic tone and arrhythmias, the mechanisms underlying the α1-AR regulation of the hERG channel are controversial. Thus, we aimed to investigate the mechanisms by which α1-AR stimulation regulates IKr.</AbstractText>α1-adrenoceptors, hERG channels, auxiliary subunits minK and MIRP1, the non PIP2-interacting mutant D-hERG (with a deletion of the 883-894 amino acids) in the C-terminal and the non PKC-phosphorylable mutant N-terminal truncated-hERG (NTK-hERG) were transfected in HEK293 cells. Cell membranes were extracted by centrifugation and the different proteins were visualized by Western blot. Potassium currents were recorded by the patch-clamp technique. IKr was recorded in isolated feline cardiac myocytes.</AbstractText>Activation of the α1-AR reduces the amplitude of IhERG and IKr through a positive shift in the activation half voltage, which reduces the channel availability at physiological membrane potentials. The intracellular pathway connecting the α1-AR to the hERG channel in HEK293 cells includes activation of the Gαq protein, PLC activation and PIP2 hydrolysis, activation of PKC and direct phosphorylation of the hERG channel N-terminal. The PKC-mediated IKr channel phosphorylation and subsequent IKr reduction after α1-AR stimulation was corroborated in feline cardiac myocytes.</AbstractText>These findings clarify the link between sympathetic nervous system hyperactivity and IKr reduction, one of the best characterized causes of torsades de pointes and ventricular fibrillation.</AbstractText>© 2016 The Author(s) Published by S. Karger AG, Basel.</CopyrightInformation> |
21,028 | Autophagy: an adaptive physiological countermeasure to cellular senescence and ischaemia/reperfusion-associated cardiac arrhythmias. | Oxidative stress placed on tissues that involved in pathogenesis of a disease activates compensatory metabolic changes, such as DNA damage repair that in turn causes intracellular accumulation of detritus and 'proteotoxic stress', leading to emergence of 'senescent' cellular phenotypes, which express high levels of inflammatory mediators, resulting in degradation of tissue function. Proteotoxic stress resulting from hyperactive inflammation following reperfusion of ischaemic tissue causes accumulation of proteinaceous debris in cells of the heart in ways that cause potentially fatal arrhythmias, in particular ventricular fibrillation (VF). An adaptive response to VF is occurrence of autophagy, an intracellular bulk degradation of damaged macromolecules and organelles that may restore cellular and tissue homoeostasis, improving chances for recovery. Nevertheless, depending on the type and intensity of stressors and inflammatory responses, autophagy may become pathological, resulting in excessive cell death. The present review examines the multilayered defences that cells have evolved to reduce proteotoxic stress by degradation of potentially toxic material beginning with endoplasmic reticulum-associated degradation, and the unfolded protein response, which are mechanisms for removal from the endoplasmic reticulum of misfolded proteins, and then progressing through the stages of autophagy, including descriptions of autophagosomes and related vesicular structures which process material for degradation and autophagy-associated proteins including Beclin-1 and regulatory complexes. The physiological roles of each mode of proteotoxic defence will be examined along with consideration of how emerging understanding of autophagy, along with a newly discovered regulatory cell type called telocytes, may be used to augment existing strategies for the prevention and management of cardiovascular disease. |
21,029 | Complications with the MICRA TPS Pacemaker System: Persistent Complete Heart Block and Late Capture Failure. | A Medtronic MICRA transcatheter pacing system (Medtronic, Minneapolis, MN, USA) was implanted in an 86-year-old patient with sick sinus syndrome and left bundle branch block after transfemoral aortic valve implantation. During implantation she developed a persistent complete heart block due to manipulation with the large-bore delivery catheter. Two weeks later, acute pacemaker dysfunction occurred due to massive increase of pacing threshold and impedance without obvious pacemaker dislocation or myocardial perforation. Recurrent capture failure was seen with pacing output set at 5 V/1.0 ms. Hence, microdislocation or fixation of the tines in the right ventricular trabeculae has to be assumed. |
21,030 | Impact of QT interval prolongation following antiarrhythmic drug therapy on left ventricular function. | We assessed whether antiarrhythmic drug-induced QT interval prolongation affects left ventricular function.</AbstractText>Study population included 54 patients with symptomatic recent onset atrial fibrillation spontaneously cardioverted to sinus rhythm. Electrocardiographic and echocardiographic studies were done before initiating and after achieving drug's steady state.</AbstractText>Significantly prolonged corrected QT interval (QTc) was noticed following only sotalol and amiodarone. The corrected precontraction time increased after sotalol (p = 0.005) and amiodarone (p = 0.017), not propafenone (p = 0.139). Analysis results between ΔEF and ΔQTc, ΔEF and ΔQTc(p), ΔE/e' and ΔQTc, ΔE/e' and ΔQTc(p) for amiodarone group were (p = 0.66, p = 0.20, p = 0.66, p = 0.33), for sotalol (p = 0.36, p = 0.51, p = 0.44, p = 0.33) and for propafenone (p = 0.38, p = 0.12, p = 0.89, p = 0.61), respectively.</AbstractText>QT interval prolongation following antiarrhythmic therapy does not affect significantly left ventricular function.</AbstractText> |
21,031 | Evaluation of a Unique Defibrillation Unit with Dual-Vector Biphasic Waveform Capabilities: Towards a Miniaturized Defibrillator. | Automated external defibrillators can provide life-saving therapies to treat ventricular fibrillation. We developed a prototype unit that can deliver a unique shock waveform produced by four independent capacitors that is delivered through two shock vectors, with the rationale of providing more robust shock pathways during emergent defibrillation. We describe the initial testing and feasibility of this unique defibrillation unit, features of which may enable downsizing of current defibrillator devices.</AbstractText>We tested our defibrillation unit in four large animal models (two canine and two swine) under general anesthesia. Experimental defibrillation thresholds (DFT) were obtained by delivery of a unique waveform shock pulse via a dual-vector pathway with four defibrillation pads (placed across the chest). DFTs were measured and compared with those of a commercially available biphasic defibrillator (Zoll M series, Zoll Medical, Chelmsford, MA, USA) tested in two different vectors. Shocks were delivered after 10 seconds of stable ventricular fibrillation and the output characteristics and shock outcome recorded. Each defibrillation series used a step-down to failure protocol to define the defibrillation threshold.</AbstractText>A total of 96 shocks were delivered during ventricular fibrillation in four large animals. In comparison to the Zoll M series, which delivered a single-vector, biphasic shock, the energy required for successful defibrillation using the unique dual-vector biphasic waveform did not differ significantly (P = 0.65).</AbstractText>Our early findings support the feasibility of a unique external defibrillation unit using a dual-vector biphasic waveform approach. This warrants further study to leverage this unique concept and work toward a miniaturized, portable shock delivery system.</AbstractText>© 2016 Wiley Periodicals, Inc.</CopyrightInformation> |
21,032 | Very high rate programming in primary prevention patients with reduced ejection fraction implanted with a defibrillator: Results from a large multicenter controlled study. | Programming implantable cardioverter-defibrillators (ICDs) with a high-rate therapy strategy has proven to be effective in reducing shocks and is associated with a reduced mortality.</AbstractText>We sought to determine the impact of a very high rate cutoff programming strategy on outcomes in patients with a primary indication for an ICD due to reduced left ventricular ejection fraction.</AbstractText>Using data from the multicenter French DAI-PP registry, this cohort-controlled study compared outcomes in 500 patients programmed with a very high rate cutoff (VH-RATE group: monitor zone 170-219 beats/min; ventricular fibrillation zone ≥220 beats/min with 13 ± 4 detection intervals) with 1500 matched control patients programmed with 1 or 2 therapy zone. All ICDs were implanted for primary prevention in patients with systolic dysfunction. Risks of events were compared after propensity score matching of sex, age, ejection fraction, New York Heart Association class, cardiomyopathy, atrial fibrillation, and type of device.</AbstractText>After a mean follow-up of 3.6 ± 2.3 years, VH-RATE programming was associated with a reduction of appropriate therapy risk (hazard ratio [HR] 0.40; 95% confidence interval [CI] 0.31-0.51; P < .0001) and inappropriate shock (HR 0.42; 95% CI 0.27-0.63; P < .0001). It was also associated with a decreased risk of sudden cardiac death (HR 0.43; 95% CI 0.17-0.99; P = .04) as compared with patients programmed with 2 therapy zones. There was no significant difference in overall survival between the groups.</AbstractText>In patients implanted with an ICD in primary prevention with left ventricular dysfunction, very high rate cutoff programming (single therapy zone ≥220 beats/min) was associated with a 60% reduction of appropriate therapies as well as inappropriate shocks, without affecting mortality.</AbstractText>Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
21,033 | Prevalence of Late Functional Tricuspid Regurgitation in Degenerative Mitral Regurgitation Surgery. | Although significant late tricuspid regurgitation (TR) may develop after surgery for degenerative mitral regurgitation (MR), the use of routine tricuspid annuloplasty is debatable. The study aim was to determine the prevalence and predictors of significant late TR after surgery for degenerative MR.</AbstractText>A total of 112 patients who had undergone surgery for degenerative MR without concomitant tricuspid valve repair (average follow up 7.7 ± 4.0 years) was studied retrospectively. The prevalence of post-surgical TR and predictors of progression were determined.</AbstractText>The majority of patients (97%) had non-significant TR (less than moderate) prior to surgery, although an overall trend of progression towards significant TR (grades 2 or 3) was noted in 17 patients (p = 0.0006). Of the 18 patients (16%) with late postoperative significant TR, only nine (8%) had severe TR with only a single referral to surgery. New-onset post-surgical atrial fibrillation was more common in patients who developed late significant TR (p = 0.002). Multivariate analysis of the pre-surgery variables, age >65 years and left ventricular dysfunction were shown to be independent predictors of late functional TR.</AbstractText>Significant progression in TR after surgery for degenerative MR was rare in this patient cohort. The impact of older age and left ventricular dysfunction at the time of surgery showed a strong association with post-surgical atrial fibrillation.</AbstractText> |
21,034 | Distant Position of Chordae from Coaptation Causes Mitral Regurgitation in Patients with Atrial Fibrillation. | The study aim was to investigate the mechanism of mitral regurgitation (MR) in lone atrial fibrillation (AF) patients using three-dimensional (3D) transesophageal echocardiography (TEE).</AbstractText>A retrospective analysis was conducted of 64 patients with AF and a normal left ventricle, and without prolapse of the mitral valve. Among these patients, significant MR was not identified in 33 cases (AF+MR- group) but was present in 31 cases (AF+MR+ group). The distance from the coaptation to the bending point of the anterior mitral leaflet (AML), where the chorda was attached, was termed the 'bending length'. The ratio of the bending length to the distance from coaptation to anterior mitral annulus was termed the 'bending ratio' (= bending length/coaptation-annulus length). The mitral annular area (MAA) fractional change was defined as follows: (MAA at late systole - MAA at early systole)/MAA at late systole × 100%). Other parameters relating to mitral valve morphology obtained using 3D TEE were measured with commercial software (QLAB, Phillips).</AbstractText>The coaptation length (CL) was smaller in the AF+MR+ group than in the AF+MR- group (p<0.001), and correlated significantly with the anteriorposterior diameter of the mitral annulus (R = 0.286, p = -0.022), MAA at mid-systole (R = -0.269, p = 0.032), MAA fractional change (R = 0.434, p <0.001), and the bending ratio (R = -0.603, p <0.001). With a multivariable analysis, the correlating factors of significant MR in lone AF patients were a decrease in MAA fractional change (p = 0.022) and an increase of the bending ratio (p = 0.009).</AbstractText>Small MAA fractional changes and the distant position of the chordae tendineae on the AML from the coaptation correlated with significant MR in AF patients with normal left ventricular systolic function.</AbstractText> |
21,035 | A novel variant in RyR2 causes familiar catecholaminergic polymorphic ventricular tachycardia. | Catecholaminergic polymorphic ventricular tachycardia is a rare familial arrhythmogenic disease. It usually occurs in juvenile patients with a structurally normal heart and causes exercise-emotion triggered syncope and sudden cardiac death. The main gene associated with catecholaminergic polymorphic ventricular tachycardia is RyR2, encoding the cardiac ryanodine receptor protein which is involved in calcium homeostasis. After the identification of a 16 year-old man presenting with exercise-induced sudden cardiac death, clinically diagnosed as catecholaminergic polymorphic ventricular tachycardia, we collected the family information and performed a comprehensive genetic analysis using Next Generation Sequencing technology. The initial electrocardiogram in the emergency department revealed ventricular fibrillation. On electrocardiogram monitoring, sinus tachycardia degenerated into bidirectional ventricular and into ventricular fibrillation. Catecholaminergic polymorphic ventricular tachycardia was clinically diagnosed in 5 of the 14 family members evaluated. There were no additional reports of seizures, pregnancy loss, neonatal death, or sudden cardiac death in family members. Genetic analysis of the index case identified only one rare novel variant p.Ile11Ser (c.32T>G) in the RyR2 gene. Subsequent familial analysis identified segregation of the genetic variant with the disease. All current evidence supports that novel p.Ile11Ser variant in the RyR2 gene is a potential disease-causing variant in catecholaminergic polymorphic ventricular tachycardia. To our knowledge, there has been no previous case report of catecholaminergic polymorphic ventricular tachycardia associated to this missense variant. |
21,036 | Comparison of Patient Characteristics and Course of Hypertensive Hypokinetic Cardiomyopathy Versus Idiopathic Dilated Cardiomyopathy. | Hypertensive hypokinetic cardiomyopathy (HHC) is defined by left ventricular (LV) systolic dysfunction with a history of systemic hypertension as the only possible cause. Although commonly encountered in clinical practice, its characterization and differences with true idiopathic dilated cardiomyopathy (IDC) are lacking. The aim of this study was to characterize the clinical instrumental features and the natural history of HHC. We analyzed the data of 4,191 patients referred to our center for newly diagnosed LV systolic dysfunction from 2005 to 2010. Of them, 310 presented idiopathic LV systolic dysfunction (LV ejection fraction <50%): 136 (44%) had a history of systemic hypertension and were defined HHC. The remaining 174 patients were considered IDC. Compared with patients with IDC, those with HHC were older (63 ± 11 vs 47 ± 14 years, p <0.001), with worse comorbidity profile, higher blood pressure, and increased LV mass. During follow-up, patients with HHC showed earlier and higher proportion of LV reverse remodeling (46% vs 21% at 6 months' follow-up). Moreover, they had a better long-term survival free from cardiovascular death/ventricular assist device/heart transplant/malignant ventricular arrhythmias (5.1 vs 12.6 in HHC and IDC, p = 0.03). Indeed, their mortality was mainly driven by noncardiovascular causes (at 10 years 9.6% vs 1.7% in HHC and IDC, p <0.001). In conclusion, HHC has a high prevalence among patients with "idiopathic" LV dysfunction. The natural history of patients with HHC is characterized by a rapid response to optimal therapy for heart failure, a favorable cardiovascular outcome, and a relevant incidence of noncardiovascular events. |
21,037 | Arrhythmias in Adults with Congenital Heart Disease: What Are Risk Factors for Specific Arrhythmias? | An increasing number of patients with congenital heart disease are now surviving into adulthood. This has also led to the emergence of complications from the underlying congenital heart disease, related surgical interventions, and associated combordities. While the prevalence of particular arrhythmias with specific congenital heart disease has been previously described, a detailed analysis of all lesions and a large number of comorbidities has not been previously published.</AbstractText>Admissions with congenital heart disease were identified in the National Inpatient Sample. Associated comorbidities were also identified for these patients. Univariate analysis was done to compare those risk factors associated with specific arrhythmias in the setting of congenital heart disease. Next, regression analysis was done to identify what patient characteristics and comorbidities were associated with increased risk of specific arrhythmias.</AbstractText>A total of 52,725,227 admissions were included in the analysis. Of these, 109,168 (0.21%) had congenital heart disease. Of those with congenital heart disease, 27,088 (25%) had an arrhythmia at some point. The most common arrhythmia in those with congenital heart disease was atrial fibrillation, which was noted in 86% of those with arrhythmia followed by atrial flutter which was noted in 20% of those with congenital heart disease. The largest burden of arrhythmia was found to be in those with tricuspid atresia with a 51% prevalence of arrhythmia in this group followed by Ebstein anomaly which had an arrhythmia prevalence of 39%. Increasing age, male gender, double outlet right ventricle, atrioventricular septal defect, heart failure, obstructive sleep apnea, transposition of the great arteries, congenitally corrected transposition, and tetralogy of Fallot were frequently noted to be independent risk factors of specific arrhythmias.</AbstractText>Approximately, 25% of adult admissions with congenital heart disease are associated with arrhythmia. The burden of arrhythmia varies by the specific lesion and other risk factors as well. Understanding of these can help in risk stratification and can help devise strategies to lower this risk.</AbstractText>© 2016 Wiley Periodicals, Inc.</CopyrightInformation> |
21,038 | Extracorporeal cardiopulmonary resuscitation for refractory cardiac arrest: A multicentre experience. | To describe the ECPR experience of two Australian ECMO centres, with regards to survival and neurological outcome, their predictors and complications.</AbstractText>Retrospective observational study of prospectively collected data on all patients who underwent extracorporeal cardiopulmonary resuscitation (ECPR) at two academic ECMO referral centres in Sydney, Australia.</AbstractText>Thirty-seven patients underwent ECPR, 25 (68%) were for in-hospital cardiac arrests. Median age was 54 (IQR 47-58), 27 (73%) were male. Initial rhythm was ventricular fibrillation or pulseless ventricular tachycardia in 20 patients (54%), pulseless electrical activity (n=14, 38%), and asystole (n=3, 8%). 27 (73%) arrests were witnessed and 30 (81%) patients received bystander CPR. Median time from arrest to initiation of ECMO flow was 45min (IQR 30-70), and the median time on ECMO was 3days (IQR 1-6). Angiography was performed in 54% of patients, and 27% required subsequent coronary intervention (stenting or balloon angioplasty 24%). A total of 13 patients (35%) survived to hospital discharge (IHCA 33% vs. OHCA 37%). All survivors were discharged with favourable neurological outcome (Cerebral Performance Category 1 or 2). Pre-ECMO lactate level was predictive of mortality OR 1.35 (1.06-1.73, p=0.016).</AbstractText>In selected patients with refractory cardiac arrest, ECPR may provide temporary support as a bridge to intervention or recovery. We report favourable survival and neurological outcomes in one third of patients and pre-ECMO lactate levels predictive of mortality. Further studies are required to determine optimum selection criteria for ECPR.</AbstractText>Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
21,039 | A case of new-onset cardiomyopathy and ventricular tachycardia in a patient receiving ibrutinib for relapsed mantle cell lymphoma. | Ibrutinib is a first-in-class inhibitor of Bruton's tyrosine kinase, which is approved for use in chronic lymphocytic leukemia, mantle cell lymphoma, and Waldenstrom's macroglobulinemia. Although ibrutinib has been linked to an increased incidence of atrial fibrillation, this is the first report of an association with nonischemic cardiomyopathy and ventricular arrhythmia. |
21,040 | A case of gingival cancer with pulmonary metastases that developed complete atrioventricular block and ventricular fibrillation as a result of myocardial metastases. | We present a rare case of gingival cancer with pulmonary metastases that developed life-threatening complete atrioventricular block and ventricular fibrillation as a result of myocardial metastases. This case suggests that implantable cardioverter defibrillators significantly improve the quality of life in these patients and maintain their performance status. |
21,041 | Noninvasive epicardial and endocardial electrocardiographic imaging of scar-related ventricular tachycardia. | The majority of life-threatening ventricular tachycardias (VTs) are sustained by heterogeneous scar substrates with narrow strands of surviving tissue. An effective treatment for scar-related VT is to modify the underlying scar substrate by catheter ablation. If activation sequence and entrainment mapping can be performed during sustained VT, the exit and isthmus of the circuit can often be identified. However, with invasive catheter mapping, only monomorphic VT that is hemodynamically stable can be mapped in this manner. For the majority of patients with poorly tolerated VTs or multiple VTs, a close inspection of the re-entry circuit is not possible. A noninvasive approach to fast mapping of unstable VTs can potentially allow an improved identification of critical ablation sites.</AbstractText>For patients who underwent catheter ablation of scar-related VT, CT scan was obtained prior to the ablation procedure and 120-lead body-surface electrocardiograms (ECGs) were acquired during induced VTs. These data were used for noninvasive ECG imaging to computationally reconstruct electrical potentials on the epicardium and on the endocardium of both ventricles. Activation time and phase maps of the VT circuit were extracted from the reconstructed electrograms. They were analyzed with respect to scar substrate obtained from catheter mapping, as well as VT exits confirmed through ablation sites that successfully terminated the VT.</AbstractText>The reconstructed re-entry circuits correctly revealed both epicardial and endocardial origins of activation, consistent with locations of exit sites confirmed from the ablation procedure. The temporal dynamics of the re-entry circuits, particularly the slowing of conduction as indicated by the crowding and zig-zag conducting of the activation isochrones, collocated well with scar substrate obtained by catheter voltage maps. Furthermore, the results indicated that some re-entry circuits involve both the epicardial and endocardial layers, and can only be properly interpreted by mapping both layers simultaneously.</AbstractText>This study investigated the potential of ECG-imaging for beat-to-beat mapping of unstable reentrant circuits. It shows that simultaneous epicardial and endocardial mapping may improve the delineation of the 3D spatial construct of a re-entry circuit and its exit. It also shows that the use of phase mapping can reveal regions of slow conduction that collocate well with suspected heterogeneous regions within and around the scar.</AbstractText>Copyright © 2016 Elsevier Inc. All rights reserved.</CopyrightInformation> |
21,042 | Pulmonary Perfusion and Ventilation during Cardiopulmonary Bypass Are Not Associated with Improved Postoperative Outcomes after Cardiac Surgery. | Clinical trials of either pulmonary perfusion or ventilation during cardiopulmonary bypass (CBP) are equivocal. We hypothesized that to achieve significant improvement in outcomes both interventions had to be concurrent.</AbstractText>Retrospective case-control study.</AbstractText>Major academic tertiary referral medical center.</AbstractText>Two hundred seventy-four consecutive patients who underwent open heart surgery with CBP 2009-2013.</AbstractText>The outcomes of 86 patients who received pulmonary perfusion and ventilation during CBP were retrospectively compared to the control group of 188 patients.</AbstractText>Respiratory complications rates were similar in both groups (33.7 vs. 33.5%), as were the rates of postoperative pneumonia (4.7 vs. 4.3%), pleural effusions (13.9 vs. 12.2%), and re-intubations (9.3 vs. 9.1%). Rates of adverse postoperative cardiac events including ventricular tachycardia (9.3 vs. 8.5%) and atrial fibrillation (33.7 vs. 28.2%) were equivalent in both groups. Incidence of sepsis (8.1 vs. 5.3%), postoperative stroke (2.3 vs. 2.1%), acute kidney injury (2.3 vs. 3.7%), and renal failure (5.8 vs. 3.7%) was likewise comparable. Despite similar transfusion requirements, coagulopathy (12.8 vs. 5.3%, p</i> = 0.031) and the need for mediastinal re-exploration (17.4 vs. 9.6%, p</i> = 0.0633) were observed more frequently in the pulmonary perfusion and ventilation group, but the difference did not reach the statistical significance. Intensive care unit (ICU) and hospital stays, and the ICU readmission rates (7.0 vs. 8.0%) were similar in both groups.</AbstractText>Simultaneous pulmonary perfusion and ventilation during CBP were not associated with improved clinical outcomes.</AbstractText> |
21,043 | High prevalence of early repolarization in the paediatric relatives of sudden arrhythmic death syndrome victims and in normal controls. | Elevation of the ECG J-point in the inferior and lateral leads (early repolarization) has been described in survivors of ventricular fibrillation (VF) arrest and occurs in adult first-degree relatives of sudden cardiac death (SCD) probands at a frequency significantly greater than in controls, raising the possibility that this could represent an independent risk factor in the aetiology of SCD. However, data on early repolarization in the paediatric population are lacking. This study aimed to assess the prevalence of early repolarization in paediatric first-degree relatives of sudden arrhythmic death syndrome (SADS) victims.</AbstractText>Paediatric relatives (aged <18 years) of SADS probands referred to the Inherited Arrhythmia Clinic at Great Ormond Street Hospital had their initial screening ECG reviewed for evidence of J-point elevation. J-point elevation was defined as QRS-ST slurring or a discrete notch in two or more inferior (II, III, aVF) or lateral (I, aVL, V4, V5, V6) leads with the change beginning >1 mV from baseline. The ECGs of 77 consecutive paediatric first-degree relatives of SADS victims from 46 families were reviewed by two assessors. J-point elevation was present in 24 patients (31%) of this patient group compared with the reported prevalence of 5-13% in the published general paediatric population (P = 0.02) and that of 19% in the internal control group (P = 0.07). Subgroup analysis according to J-point elevation and ST segment morphologies showed a significantly higher prevalence of inferior early repolarization 0.1-0.2 mV in the study group compared with controls (75 vs. 38%; P = 0.02).</AbstractText>Inferolateral J-point elevation occurs in a substantial proportion of paediatric first-degree relatives of SADS probands with a similar prevalence to that described in adults. This suggests that early repolarization could be an important inherited trait when evaluating relatives of SADS victims. However, prospective follow-up of this group of children is important to establish the implication of this finding in future risk stratification, given the apparently high prevalence in normal individuals.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
21,044 | Cardiovascular outcomes in patients with intraventricular conduction blocks: A sixteen-year follow-up in a state-wide database. | To assess the adverse clinical effects of left anterior hemiblock alone or in combination with right bundle branch block and of complete left bundle branch block in comparison with isolated right bundle branch block and the relationship of these effects with altered mechanoelectric factors resulting in left ventricular dysfunction.</AbstractText>In a 16-year follow-up study using a statewide database, we studied the occurrence of mortal and morbid cardiovascular (CV) events among patients without apparent ischemic heart disease who had left anterior hemiblock (LAHB, n=4273, right bundle branch block (RBBB) with LAHB (BFBB, n=1857) and left bundle branch block (LBBB, n=9484 compared to isolated RBBB (n=25288).</AbstractText>After adjustment for demographics, co-morbidities and insurance, LAHB was associated with a significant excess risk of all-cause death (HR 1.134, 95% CI 1.061-1.213, p=0.0002) and CV death (HR 1.329, 95% CI 1.174-1.501, p<0.0001). BFBB was associated with excess HF (HR 1.190, 95% CI 1.048-1.351, p<0.0071), all-cause death (HR 1.440, 95% CI 1.045-1.252, p=0.0036) and CV death (HR 1.210, 95% CI 1.020-1.436, p<0.0001). LBBB was associated with an excess risk of MR (HR 1.307, 95% CI 1.116-1.530, p<0.0009), HF 1.177, 95% CI1.097-1.263, p<0.0001) and CV death (HR 1.220, 95% CI 1.106-1.345, p<0.0001).</AbstractText>In patients without apparent ischemic heart disease, the presence of LAHB alone or in combination with RBBB imparts increased risk of CV and all-cause death compared to isolated RBBB. BFBB is also associated with an increased risk of HF.</AbstractText>Copyright © 2016 Hellenic Society of Cardiology. Published by Elsevier B.V. All rights reserved.</CopyrightInformation> |
21,045 | Riata silicone defibrillation lead with normal electrical measures at routine ambulatory check: The role of high-voltage shock testing. | To describe our experience with shock testing for the evaluation of patients with Riata™ leads.</AbstractText>Among 51 patients with normal baseline electrical parameters, 20 died during follow-up. Of the remaining 31 patients, 15 underwent the test: In 10 cases a defibrillation testing with ventricular fibrillation (VF) induction and in 5 cases a R-wave-synchronized shock (> 20 J, without inducing VF). The test was performed under sedation with Midazolam.</AbstractText>Twelve patients (80%) had a normal behavior during shock testing: In 8 cases induced VF was correctly detected and treated; in 4 cases of R-wave-synchronized shock electrical parameters remained stable and normal. Three patients (20%) failed the test. One patient with externalized conductors showed a sudden drop of high-voltage impedance (< 10 Ohm) after a 25 J R-wave-synchronized shock. Two other patients with externalized conductors, undergoing defibrillation testing, showed a short-circuit during shock delivery and the implantable cardioverter defibrillator was unable to interrupt VF.</AbstractText>In Riata™ leads the delivery of a low current during routine measurement of high-voltage impedance may not reveal a small short circuit, that can only be evident by attempting to deliver a true shock, either for spontaneous arrhythmias or in the context of a shock testing.</AbstractText> |
21,046 | Differences Between Access to Follow-Up Care and Inappropriate Shocks Based on Insurance Status of Implantable Cardioverter Defibrillator Recipients. | Differences in implantable cardioverter defibrillator (ICD) utilization based on insurance status have been described, but little is known about postimplant follow-up patterns associated with insurance status and outcomes. We collected demographic, clinical, and device data from 119 consecutive patients presenting with ICD shocks. Insurance status was classified as uninsured/Medicaid (uninsured) or private/Health Maintenance Organization /Medicare (insured). Shock frequencies were analyzed before and after a uniform follow-up pattern was implemented regardless of insurance profile. Uninsured patients were more likely to present with an inappropriate shock (63% vs 40%, p = 0.01), and they were more likely to present with atrial fibrillation (AF) as the shock trigger (37% vs 19%, p = 0.04). Uninsured patients had a longer interval between previous physician contact and index ICD shock (147 ± 167 vs 83 ± 124 days, p = 0.04). Patients were followed for a mean of 521 ± 458 days after being enrolled in a uniform follow-up protocol, and there were no differences in the rate of recurrent shocks based on insurance status. In conclusion, among patients presenting with an ICD shock, underinsured/uninsured patients had significantly longer intervals since previous physician contact and were more likely to present with inappropriate shocks and AF, compared to those with private/Medicare coverage. After the index shock, both groups were followed uniformly, and the differences in rates of inappropriate shocks were mitigated. This observation confirms the importance of regular postimplant follow-up as part of the overall ICD management standard. |
21,047 | Relation of Functional Status to Risk of Development of Atrial Fibrillation. | Identifying patients at risk is now important as there are demonstrable ways to alter disease progression which could potentially prevent atrial fibrillation (AF) and its complications. We sought whether impaired functional capacity was associated with risk of AF, independent of myocardial dysfunction. In this community-based study, asymptomatic participants aged ≥65 years were recruited if they had ≥1 risk factor (e.g., hypertension, diabetes mellitus, and obesity). Participants underwent baseline echocardiography (including measurement of myocardial mechanics) and six-minute walk test. The CHARGE-AF score was used to calculate 5-year risk of developing AF. Receiver operating characteristic curves were used to assess for independent risk factors for AF. A total of 607 patients (age 71 ± 5 years, men 47%) were studied at baseline and followed for at least 6 months. Patients in the higher AF risk groups were older and had increased rates of hypertension, diabetes mellitus, and ischemic heart disease (p <0.05). Greater AF risk was associated with lower exercise capacity, independent of lower mean global longitudinal strain, global circumferential strain, greater mean E/e' ratio, indexed left atrial volume and LV mass. Multivariate linear regression confirmed association of LV and functional capacity parameters with AF risk. Although functional capacity is impaired in AF, this association precedes the onset of AF. In conclusion, poor functional status is associated with AF risk, independent of LV function. |
21,048 | Does the choice of definition for defibrillation and CPR success impact the predictability of ventricular fibrillation waveform analysis? | Quantitative analysis of ventricular fibrillation (VF), such as amplitude spectral area (AMSA), predicts shock outcomes. However, there is no uniform definition of shock/cardiopulmonary resuscitation (CPR) success in out-of-hospital cardiac arrest (OHCA). The objective of this study is to investigate post-shock rhythm variations and the impact of shock/CPR success definition on the predictability of AMSA.</AbstractText>A total of 554 shocks from 257 OHCA patients with VF as initial rhythm were analyzed. Post-shock rhythms were analyzed every 5s up to 120s and annotated as VF, asystole (AS) and organized rhythm (OR) at serial time intervals. Three shock/CPR success definitions were used to evaluate the predictability of AMSA: (1) termination of VF (ToVF); (2) return of organized electrical activity (ROEA); (3) return of potentially perfusing rhythm (RPPR).</AbstractText>Rhythm changes occurred after 54.5% (N=302) of shocks and 85.8% (N=259) of them occurred within 60s after shock delivery. The observed post-shock rhythm changes were (1) from AS to VF (24.9%), (2) from OR to VF (16.1%), and (3) from AS to OR (12.1%). The area under the receiver operating characteristic curve (AUC) for AMSA as a predictor of shock/CPR success reached its maximum 60s post-shock. The AUC was 0.646 for ToVF, 0.782 for ROEA, and 0.835 for RPPR (p<0.001) respectively.</AbstractText>Post-shock rhythm is unstable in the first minute after the shock. The predictability of AMSA varies depending on the definition of shock/CPR success and performs best with the return of potentially perfusing rhythm endpoint for OHCA.</AbstractText>Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
21,049 | Intermuscular Two-Incision Technique for Subcutaneous Implantable Cardioverter Defibrillator Implantation: Results from a Multicenter Registry. | The traditional technique for subcutaneous implantable cardioverter defibrillator (S-ICD) implantation, which involves three incisions and a subcutaneous pocket, is associated with possible complications, including inappropriate interventions. The aim of this prospective multicenter study was to evaluate the efficacy and safety of an alternative intermuscular two-incision technique for S-ICD implantation.</AbstractText>The study population included 36 consecutive patients (75% male, mean age 44 ± 12 years [range 20-69]) who underwent S-ICD implantation using the intermuscular two-incision technique. This technique avoids the superior parasternal incision for the lead placement and consists of creating an intermuscular pocket between the anterior surface of the serratus anterior and the posterior surface of the latissimus dorsi muscles instead of a subcutaneous pocket.</AbstractText>All patients were successfully implanted in the absence of any procedure-related complications with a successful 65-J standard polarity defibrillation threshold testing, except in one, who received a second successful shock after pocket revision. During a mean follow-up of 10 months (range 3-30), no complications requiring surgical revision were observed. At device interrogation, stable sensing without interferences was observed in all patients. Two patients (5.5%) experienced appropriate and successful shock on ventricular fibrillation and in four patients (11%), a total of seven nonsustained self-terminated ventricular tachycardias were correctly detected. No inappropriate interventions were observed.</AbstractText>Our experience suggests that the two-incision intermuscular technique is a safe and efficacious alternative to the current technique for S-ICD implantation that may help reducing complications including inappropriate interventions and offer a better cosmetic outcome, especially in thin individuals.</AbstractText>© 2016 The Authors. Pacing and Clinical Electrophysiology published by Wiley Periodicals, Inc.</CopyrightInformation> |
21,050 | Hemodialysis-induced repolarization abnormalities on ECG are influenced by serum calcium levels and ultrafiltration volumes. | Hemodialysis (HD) patients are known to have high cardiovascular mortality rate. Sudden cardiac death (SCD) due to arrhythmias causes most of the cardiac deaths. HD per se may lead to ECG abnormalities and ventricular arrhythmias. Monitoring ECG parameters such as corrected QT interval, QT dispersion (QTd), Tpe interval may be useful to stratify the patients with high risk of arrhythmia and SCD. Herein we aimed to investigate the effects of changes in serum electrolyte levels and pH on ECG parameters before and after the HD.</AbstractText>A total of 50 chronic HD patients (mean age 58 ± 19; male 27) were enrolled. Patients with unmeasurable T waves; atrial fibrillation; bundle branch block; use of class I or class III antiarrhythmic drugs were excluded. Serum potassium, magnesium, calcium, urea, creatinine and pH were measured before and after HD treatment. Standard surface 12-lead ECGs were recorded before and after HD. QTc, QTd, Tpe, JT interval, P-wave-duration, P-wave dispersion were determined.</AbstractText>Serum potassium and magnesium decreased, and calcium, pH and bicarbonate levels increased; QRS and Tpe interval were increased after HD. Basal Tpe was correlated with urea (r = 0.31, p = 0.02). Tpe interval was higher in hypocalcemic compared to normocalcemic patients (77 ± 11 vs 70 ± 9 ms, p = 0.02). ∆Tpe was correlated with ∆calcium (r = -0.32, p = 0.02). Basal QTc was correlated with calcium (r = -0.62, p < 0.001). ∆QTc was correlated with basal calcium (r = 0.39, p = 0.005) and ∆calcium (r = -0.46, p < 0.001). Basal JT was correlated with calcium (r = -0.55, p < 0.001). ∆JT was correlated with pH (r = 0.35, p = 0.01), ∆calcium (r = -0.53, p < 0.001) and ∆magnesium (r = -0.30, p = 0.03). Before HD, 12 patients (12%) were hypermagnesemic of whom JT intervals were lower (314 ± 20 vs 332 ± 23 ms, p = 0.02). Ultrafiltration per body weight was associated with ∆QTc (r = -0.40, p = 0.007) and ∆JT (r = -0.36, p = 0.01).</AbstractText>QRS and Tpe intervals were increased after HD. Tpe interval was longer in hypocalcemic patients. Change in Tpe was negatively associated with the change in calcium. Ultrafiltration was associated with ∆QTc and ∆JT. Calcium and ultrafiltration seem to be the most important determinants of ECG parameters of HD-induced repolarization abnormalities.</AbstractText> |
21,051 | Significance and clinical characteristics of atrial fibrillation post epicardial access. | Epicardial access (EpiAcc) has become an important adjunct for ventricular tachycardia (VT) or premature ventricular complex (PVC) ablation. We hypothesized that post-procedural pericarditis may lead to an increased risk of atrial fibrillation (AF), and therefore assessed the incidence and clinical impact of post-procedural AF in patients undergoing EpiAcc.</AbstractText>We reviewed the records of all patients who underwent EpiAcc as part of an ablation procedure between January 1, 2004 and July 31, 2014 at Mayo Clinic Rochester. AF occurrence was determined by clinical documentation or electrocardiographic recordings post procedure.</AbstractText>Epicardial access was obtained in 170 pts (indication 110 VT and 60 PVC). The mean age was 53 ± 16 years and 122 (72%) were male. Seven (4.1%) patients developed AF within 7 days of the procedure, at a mean of 49 ± 18 h post procedure; it was paroxysmal in all patients with an average duration 6.0 ± 5.5 h (range 2-18). All patients spontaneously converted to sinus rhythm; but 3 needed rate control with AV nodal blockade (calcium channel blockers [n = 2] or beta blockers [n = 1]). One patient out of 60 who received intrapericardial steroids developed AF (2%), while of the 110 who did not receive steroids, 6 developed AF (5%) (p = 0.42). During average follow-up 2.3 years, there were no documented recurrences of atrial fibrillation in these patients.</AbstractText>Atrial fibrillation following epicardial access is infrequent. When it occurs, it tends to be paroxysmal in nature and without severe symptoms. Administration of intrapericardial steroids did not affect the rate of AF post procedure; further studies however are needed to define their role.</AbstractText> |
21,052 | Is current training in basic and advanced cardiac life support (BLS & ACLS) effective? A study of BLS & ACLS knowledge amongst healthcare professionals of North-Kerala. | Healthcare professionals are expected to have knowledge of current basic and advanced cardiac life support (BLS/ACLS) guidelines to revive unresponsive patients.</AbstractText>A cross-sectional study was conducted to evaluate the current practices and knowledge of BLS/ACLS principles among healthcare professionals of North-Kerala using pretested self-administered structured questionnaire. Answers were validated in accordance with American Heart Association's BLS/ACLS teaching manual and the results were analysed.</AbstractText>Among 461 healthcare professionals, 141 (30.6%) were practicing physicians, 268 (58.1%) were nurses and 52 (11.3%) supporting staff. The maximum achievable score was 20 (BLS 15/ACLS 5). The mean score amongst all healthcare professionals was 8.9±4.7. The mean score among physicians, nurses and support staff were 8.6±3.4, 9±3.6 and 9±3.3 respectively. The majority of healthcare professionals scored ≤50% (237, 51.4%); 204 (44.3%) scored 51%-80% and 20 (4.34%) scored >80%. Mean scores decreased with age, male sex and across occupation. Nurses who underwent BLS/ACLS training previously had significantly higher mean scores (10.2±3.4) than untrained (8.2±3.6, P</i>=0.001). Physicians with <5 years experience (P</i>=0.002) and nurses in the private sector (P</i>=0.003) had significantly higher scores. One hundred and sixty three (35.3%) healthcare professionals knew the correct airway opening manoeuvres like head tilt, chin lift and jaw thrust. Only 54 (11.7%) respondents were aware that atropine is not used in ACLS for cardiac arrest resuscitation and 79 (17.1%) correctly opted ventricular fibrillation and pulseless ventricular tachycardia as shockable rhythms. The majority of healthcare professionals (356, 77.2%) suggested that BLS/ACLS be included in academic curriculum.</AbstractText>Inadequate knowledge of BLS/ACLS principles amongst healthcare professionals, especially physicians, illuminate lacunae in existing training systems and merit urgent redressal.</AbstractText> |
21,053 | Comparative Risk of Ventricular Arrhythmia and Sudden Cardiac Death Across Antidepressants in Patients With Depressive Disorders. | We aimed to evaluate the risk of ventricular arrhythmia (VA) and/or sudden cardiac death (SCD) associated with antidepressant use.</AbstractText>A cohort study was conducted using data from Taiwan's National Health Insurance Research Database from 2001 to 2012. A total of 793,460 new antidepressant users with depressive disorders were enrolled in the study. Outcomes were defined as the first principal diagnosis of VA or SCD in the emergency department or hospital discharge records. Cox proportional hazards models with stratification of propensity score deciles were used to evaluate the relative risk of VA/SCD for antidepressants compared with selective serotonin reuptake inhibitors (SSRIs).</AbstractText>A total of 245 VA/SCD events occurred. The incidence rate of VA/SCD among antidepressant users was 1.5 per 1000 person-years (95% confidence interval [CI], 1.3-1.7). Compared with SSRIs, the risk of VA/SCD was significantly lower for tricyclic or tetracyclic antidepressant (TCAs) (adjusted hazards ratio [aHR], 0.54; 95% CI, 0.36-0.83), but not other antidepressant classes. However, use of moderate- to high-dose TCAs carried a higher risk than low-dose TCAs (aHR, 4.37; 95% CI, 1.23-15.60). Antidepressant polypharmacy was associated with an increased risk of VA/SCD (aHR, 1.63; 95% CI, 1.07-2.49).</AbstractText>There was no difference in VA/SCD risk across antidepressant classes except that TCAs were associated with a lower risk than SSRIs. However, the observed comparative risk of TCAs might be attributable to low-dose TCA use, which is quite common in current clinical practice. It would be of importance to carry out further investigations to scrutinize the influence of antidepressants on VA/SCD.</AbstractText> |
21,054 | Incidence and predictors of sudden death, major conduction defects and sustained ventricular tachyarrhythmias in 1388 patients with myotonic dystrophy type 1. | To describe the incidence and identify predictors of sudden death (SD), major conduction defects and sustained ventricular tachyarrhythmias (VTA) in myotonic dystrophy type 1 (DM1).</AbstractText>We retrospectively enrolled 1388 adults with DM1 referred to six French medical centres between January 2000 and October 2013. We confirmed their vital status, classified all deaths, and determined the incidence of major conduction defects requiring permanent pacing and sustained VTA. We searched for predictors of overall survival, SD, major conduction defects, and sustained VTA by Cox regression analysis. Over a median 10-year follow-up, 253 (18.2%) patients died, 39 (3.6%) suddenly. Analysis of the cardiac rhythm at the time of the 39 SD revealed sustained VTA in 9, asystole in 5, complete atrioventricular block in 1 and electromechanical dissociation in two patients. Non-cardiac causes were identified in the five patients with SD who underwent autopsies. Major conduction defects developed in 143 (19.3%) and sustained VTA in 26 (2.3%) patients. By Cox regression analysis, age, family history of SD and left bundle branch block were independent predictors of SD, while age, male sex, electrocardiographic conduction abnormalities, syncope, and atrial fibrillation were independent predictors of major conduction defects; non-sustained VTA was the only predictor of sustained VTA.</AbstractText>SD was a frequent mode of death in DM1, with multiple mechanisms involved. Major conduction defects were by far more frequent than sustained VTA, whose only independent predictor was a personal history of non-sustained VTA. ClinicalTrials.gov no: NCT01136330.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For Permissions, please email: journals.permissions@oup.com.</CopyrightInformation> |
21,055 | Development and impact of arrhythmias after the Norwood procedure: A report from the Pediatric Heart Network. | The study objective was to determine the predictors of new-onset arrhythmia among infants with single-ventricle anomalies during the post-Norwood hospitalization and the association of those arrhythmias with postoperative outcomes (ventilator time and length of stay) and interstage mortality.</AbstractText>After excluding patients with preoperative arrhythmias, we used data from the Pediatric Heart Network Single Ventricle Reconstruction Trial to identify risk factors for tachyarrhythmias (atrial fibrillation, atrial flutter, supraventricular tachycardia, junctional ectopic tachycardia, and ventricular tachycardia) and atrioventricular block (second or third degree) among 544 eligible patients. We then determined the association of arrhythmia with outcomes during the post-Norwood hospitalization and interstage period, adjusting for identified risk factors and previously published factors.</AbstractText>Tachyarrhythmias were noted in 20% of subjects, and atrioventricular block was noted in 4% of subjects. Potentially significant risk factors for tachyarrhythmia included the presence of modified Blalock-Taussig shunt (P = .08) and age at Norwood (P = .07, with risk decreasing each day at age 8-20 days); the only significant risk factor for atrioventricular block was undergoing a concomitant procedure at the time of the Norwood (P = .001), with the greatest risk being in those undergoing a tricuspid valve procedure. Both tachyarrhythmias and atrioventricular block were associated with longer ventilation time and length of stay (P < .001 for all analyses). Tachyarrhythmias were not associated with interstage mortality; atrioventricular block was associated with mortality among those without a pacemaker in the unadjusted analysis (hazard ratio, 2.3; P = .02), but not after adding covariates.</AbstractText>Tachyarrhythmias are common after the Norwood procedure, but atrioventricular block may portend a greater risk for interstage mortality.</AbstractText>Copyright © 2016 The American Association for Thoracic Surgery. All rights reserved.</CopyrightInformation> |
21,056 | Impaired Left Atrial Function in Fabry Disease: A Longitudinal Speckle-Tracking Echocardiography Study. | Fabry disease (FD) is characterized by the accumulation of sphingolipids in multiple organs, including the left atrium. It is uncertain if the left atrial (LA) reservoir, conduit, and contractile functions evaluated by speckle-tracking echocardiography are affected in Fabry cardiomyopathy and whether enzyme replacement therapy can improve LA function.</AbstractText>In this retrospective cohort study, LA strain, strain rates, and phasic LA volumes were studied in 50 patients with FD and compared with values in 50 healthy control subjects.</AbstractText>All three LA phasic functions were altered. Peak positive strain (reservoir function) was 38.9 ± 14.9% versus 46.5 ± 10.9% (P = .004), and late diastolic strain (contractile function) was 12.6 ± 5.9% versus 15.6 ± 5.3% (P = .010). In 15 patients who started enzyme replacement therapy during the study, most of the LA parameters improved at 1-year follow-up (peak positive strain from 32.0 ± 13.5% to 38.0 ± 13.5%, P = .006), whereas there was a trend toward deterioration in 15 patients who never received treatment (peak positive strain from 47.3 ± 10.8% to 41.3 ± 9.3%, P = .058). Nine patients with FD (21%) experienced new-onset atrial fibrillation or stroke during 4-year follow-up. By univariate analysis, peak positive strain and early diastolic strain demonstrated significant associations with clinical events, surpassing conventional echocardiographic parameters and clinical characteristics.</AbstractText>LA reservoir, conduit, and contractile functions by speckle-tracking echocardiography were all affected in FD. Enzyme replacement therapy improved LA function. LA strain parameters were associated with atrial fibrillation and stroke.</AbstractText>Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
21,057 | Esmolol before cardioplegia and as cardioplegia adjuvant reduces cardiac troponin release after cardiac surgery. A randomized trial. | Cardioplegic solutions are the standard in myocardial protection during cardiac surgery, since they interrupt the electro-mechanical activity of the heart and protect it from ischemia during aortic cross-clamping. Nevertheless, myocardial damage has a strong clinical impact. We tested the hypothesis that the short-acting beta-blocker esmolol, given immediately before cardiopulmonary bypass and as a cardioplegia additive, would provide an extra protection to myocardial tissue during cardiopulmonary bypass by virtually reducing myocardial activity and, therefore, oxygen consumption to zero.</AbstractText>This was a single-centre, double-blind, placebo-controlled, parallel-group phase IV trial. Adult patients undergoing elective valvular and non-valvular cardiac surgery with end diastolic diameter >60 mm and ejection fraction <50% were enrolled. Patients were randomly assigned to receive either esmolol, 1 mg/kg before aortic cross-clamping and 2 mg/kg with Custodiol®</sup> crystalloid cardioplegia or equivolume placebo. The primary end-point was peak postoperative troponin T concentration. Troponin was measured at Intensive Care Unit arrival and at 4, 24 and 48 hours. Secondary endpoints included ventricular fibrillation after cardioplegic arrest, need for inotropic support and intensive care unit and hospital stay.</AbstractText>We found a reduction in peak postoperative troponin T, from 1195 ng/l (690-2730) in the placebo group to 640 ng/l (544-1174) in the esmolol group (p=0.029) with no differences in Intensive Care Unit stay [3 days (1-6) in the placebo group and 3 days (2-5) in the esmolol group] and hospital stay [7 days (6-10) in the placebo group and 7 days (6-12) in the esmolol group]. Troponin peak occurred at 24 hours for 12 patients (26%) and at 4 hours for the others (74%). There were no differences in other secondary end-points.</AbstractText>Adding esmolol to the cardioplegia in high-risk patients undergoing elective cardiac surgery reduces peak postoperative troponin levels. Further investigation is necessary to assess esmolol effects on major clinical outcomes.</AbstractText> |
21,058 | Scn2b Deletion in Mice Results in Ventricular and Atrial Arrhythmias. | Mutations in SCN2B, encoding voltage-gated sodium channel β2-subunits, are associated with human cardiac arrhythmias, including atrial fibrillation and Brugada syndrome. Because of this, we propose that β2-subunits play critical roles in the establishment or maintenance of normal cardiac electric activity in vivo.</AbstractText>To understand the pathophysiological roles of β2 in the heart, we investigated the cardiac phenotype of Scn2b null mice. We observed reduced sodium and potassium current densities in ventricular myocytes, as well as conduction slowing in the right ventricular outflow tract region. Functional reentry, resulting from the interplay between slowed conduction, prolonged repolarization, and increased incidence of premature ventricular complexes, was found to underlie the mechanism of spontaneous polymorphic ventricular tachycardia. Scn5a transcript levels were similar in Scn2b null and wild-type ventricles, as were levels of Nav</sub>1.5 protein, suggesting that similar to the previous work in neurons, the major function of β2-subunits in the ventricle is to chaperone voltage-gated sodium channel α-subunits to the plasma membrane. Interestingly, Scn2b deletion resulted in region-specific effects in the heart. Scn2b null atria had normal levels of sodium current density compared with wild type. Scn2b null hearts were more susceptible to atrial fibrillation, had increased levels of fibrosis, and higher repolarization dispersion than wild-type littermates.</AbstractText>Genetic deletion of Scn2b in mice results in ventricular and atrial arrhythmias, consistent with reported SCN2B mutations in human patients.</AbstractText>© 2016 American Heart Association, Inc.</CopyrightInformation> |
21,059 | Gender differences in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy: Clinical manifestations, electrophysiological properties, substrate characteristics, and prognosis of radiofrequency catheter ablation. | Gender differences in the penetrance and clinical expression of genetic mutations have been reported in patients with arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C). Our study aimed at clarifying the impact of gender on ventricular substrates and clinical outcomes after radiofrequency catheter ablation (RFCA).</AbstractText>Patients with ARVD/C underwent RFCA for drug-refractory ventricular arrhythmias (VAs) were consecutively enrolled. Baseline characteristics, electrocardiograms, ventricular substrates, and VA recurrences after RFCA were extracted for comparison between genders.</AbstractText>A total of 70 consecutive unselected patients with definite ARVD/C (36 men [51%], age 45±14years) were studied. Male patients had a higher incidence of sustained ventricular tachycardia and ventricular fibrillation or sudden cardiac arrest as initial manifestations. Electroanatomical mapping demonstrated that men with ARVD/C had a larger epicardial RV unipolar low-voltage zone, a larger endocardial and epicardial area with late potentials, and longer local abnormal ventricular activity. Cox regression analysis demonstrated that gender and late potential area predicted the recurrences of VAs.</AbstractText>Patients with ARVD/C displayed different characteristics of VAs and substrate properties between men and women. Male gender and the presence of larger area of abnormal electrograms independently predicted VA recurrences after RFCA.</AbstractText>Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.</CopyrightInformation> |
21,060 | Arrhythmogenic Right Ventricular Cardiomyopathy: Clinical Course and Predictors of Arrhythmic Risk. | Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a leading cause of sudden cardiac death, but its progression over time and predictors of arrhythmias are still being defined.</AbstractText>This study sought to describe the clinical course of ARVC and occurrence of life-threatening arrhythmic events (LAE) and cardiovascular mortality; identify risk factors associated with increased LAE risk; and define the response to therapy.</AbstractText>We determined the clinical course of 301 consecutive patients with ARVC using the Kaplan-Meier method adjusted to avoid the bias of delayed entry. Predictors of LAE over 5.8 years of follow-up were determined with Cox multivariable analysis. Treatment efficacy was assessed comparing LAE rates during matched time intervals.</AbstractText>A first LAE occurred in 1.5 per 100 person-years between birth and age 20 years, in 4.0 per 100 person-years between ages 21 and 40 years, and in 2.4 per 100 person-years between ages 41 and 60 years. Cumulative probability of a first LAE at follow-up was 14% at 5 years, 23% at 10 years, and 30% at 15 years. Higher risk of LAE was predicted by atrial fibrillation (hazard ratio [HR]: 4.38; p = 0.002), syncope (HR: 3.36; p < 0.001), participation in strenuous exercise after the diagnosis (HR: 2.98; p = 0.028), hemodynamically tolerated sustained monomorphic ventricular tachycardia (HR: 2.19; p = 0.023), and male sex (HR: 2.49; p = 0.012). No difference was observed in the occurrence of LAE before and after treatment with amiodarone, beta-blockers, sotalol, or ablation. A total of 81 patients received an implantable cardioverter-defibrillator, 34 were successfully defibrillated.</AbstractText>The high risk of life-threatening arrhythmias in patients with ARVC spans from adolescence to advanced age, reaching its peak between ages 21 and 40 years. Atrial fibrillation, syncope, participation in strenuous exercise after the diagnosis of ARVC, hemodynamically tolerated sustained monomorphic ventricular tachycardia, and male sex predicted lethal arrhythmias at follow-up. The lack of efficacy of antiarrhythmic therapy and the life-saving role of the implantable cardioverter-defibrillator highlight the importance of risk stratification for patient management.</AbstractText>Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
21,061 | Comparison of Ventricular Inducibility with Late Gadolinium Enhancement and Myocardial Inflammation in Endomyocardial Biopsy in Patients with Dilated Cardiomyopathy. | Risk stratification of patients with non-ischemic dilated cardiomyopathy remains a matter of debate in the era of device implantation.</AbstractText>We investigated associations between histopathological findings, contrast-enhanced cardiac MRI and the inducibility of ventricular tachycardia (VT) or fibrillation (VF) in programmed ventricular stimulation.</AbstractText>56 patients with impaired left ventricular ejection fraction (LVEF≤50%, mean 36.6±10.5%) due to non-ischemic dilated cardiomyopathy underwent cardiac MRI, programmed ventricular stimulation, and endomyocardial biopsy and were retrospectively investigated. Inducibility was defined as sustained mono- or polymorphic VT or unstable VT/VF requiring cardioversion/defibrillation. Primary study endpoint was defined as the occurrence of hemodynamically relevant VT/VF and/or adequate ICD-therapy during follow-up.</AbstractText>Endomyocardial biopsy detected cardiac fibrosis in 18 (32.1%) patients. Cardiac MRI revealed 35 (62.5%) patients with positive late gadolinium enhancement. VT/VF was induced in ten (17.9%) patients during programmed ventricular stimulation. Monomorphic VT was inducible in 70%, while 20% of patients showed polymorphic VT. One patient (10%) presented with VF. Inducibility correlated significantly with the presence of positive late gadolinium enhancement in cardiac MRI (p<0.01). We could not find a significant association between inducibility and the degree of cardiac inflammation and fibrosis in non-site directed routine right ventricular endomyocardial biopsy. During a mean follow-up of 2.6 years, nine (16.1%) patients reached the primary endpoint. Monomorphic VTs were found in 66.7% patients and were terminated by antitachycardia pacing therapy. One patient with polymorphic VT and two patients with VF received adequate therapy by an ICD-shock. However, inducibility did not correlate with the occurrence of endpoints.</AbstractText>Inducibilty during programmed ventricular stimulation is associated with positive late gadolinium enhancement in cardiac MRI of patients with non-ischemic dilated cardiomyopathy. The presence of myocardial fibrosis or inflammation in undirected endomyocardial biopsy does not seem to be sufficient to predict future ventricular arrhythmias.</AbstractText> |
21,062 | A hemodynamic-directed approach to pediatric cardiopulmonary resuscitation (HD-CPR) improves survival. | Most pediatric in-hospital cardiac arrests (IHCAs) occur in ICUs where invasive hemodynamic monitoring is frequently available. Titrating cardiopulmonary resuscitation (CPR) to the hemodynamic response of the individual improves survival in preclinical models of adult cardiac arrest. The objective of this study was to determine if titrating CPR to systolic blood pressure (SBP) and coronary perfusion pressure (CoPP) in a pediatric porcine model of asphyxia-associated ventricular fibrillation (VF) IHCA would improve survival as compared to traditional CPR.</AbstractText>After 7min of asphyxia followed by VF, 4-week-old piglets received either hemodynamic-directed CPR (HD-CPR; compression depth titrated to SBP of 90mmHg and vasopressor administration to maintain CoPP ≥20mmHg); or Standard Care (compression depth 1/3 of the anterior-posterior chest diameter and epinephrine every 4min). All animals received CPR for 10min prior to the first defibrillation attempt. CPR was continued for a maximum of 20min. Protocolized intensive care was provided to all surviving animals for 4h. The primary outcome was 4-h survival.</AbstractText>Survival rate was greater with HD-CPR (12/12) than Standard Care (6/10; p=0.03). CoPP during HD-CPR was higher compared to Standard Care (point estimate +8.1mmHg, CI95</sub>: 0.5-15.8mmHg; p=0.04). Chest compression depth was lower with HD-CPR than Standard Care (point estimate -14.0mm, CI95: -9.6 to -18.4mm; p<0.01). Prior to the first defibrillation attempt, more vasopressor doses were administered with HD-CPR vs. Standard Care (median 5 vs. 2; p<0.01).</AbstractText>Hemodynamic-directed CPR improves short-term survival compared to standard depth-targeted CPR in a porcine model of pediatric asphyxia-associated VF IHCA.</AbstractText>Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
21,063 | Characteristics and outcomes of young adults who suffered an out-of-hospital cardiac arrest (OHCA). | There is paucity of data examining the incidence and outcomes of young OHCA adults. The aim of this study is to determine the outcomes and characteristics of young adults who suffered an OHCA and identify factors that are associated with favourable neurologic outcomes.</AbstractText>All EMS-attended OHCA adults between the ages of 16 and 35 years in the Pan-Asian Resuscitation Outcomes Study (PAROS) registry were analysed. The primary outcome was favourable neurologic outcome (Cerebral Performance Category 1 or 2) at hospital discharge or at 30th day post OHCA if not discharged. Regression analysis was performed to identify factors associated with favourable neurologic outcomes.</AbstractText>66,780 OHCAs were collected between January 2009 and December 2013; 3244 young OHCAs had resuscitation attempted by emergency medical services (EMS). 56.8% of patients had unwitnessed arrest; 47.9% were of traumatic etiology. 17.2% of patients (95% CI: 15.9-18.5%) had return of spontaneous circulation; 7.8% (95% CI: 6.9-8.8%) survived to one month; 4.6% (95% CI: 4.0-5.4%) survived with favourable neurologic outcomes. Factors associated with favourable neurologic outcomes include witnessed arrest (adjusted RR=2.42, p-value<0.0001), bystander CPR (adjusted RR=1.57, p-value=0.004), first arrest shockable rhythm (adjusted RR=27.24, p-value<0.0001), and cardiac etiology (adjusted RR=3.99, p-value<0.0001).</AbstractText>OHCA among young adults are not uncommon. Traumatic OHCA, occurring most frequently in young adults had dismal prognosis. First arrest rhythms of VF/VT/unknown shockable rhythm, cardiac etiology, bystander-witnessed arrest, and bystander CPR were associated with favourable neurological outcomes. The results of the study would be useful for planning preventive and interventional strategies, improving EMS, and guiding future research.</AbstractText>Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
21,064 | [Immediate and delayed outcomes after electrical injury. A guide for clinicians]. | Immediate and delayed outcomes after electrical injury. A guide for clinicians In Sweden about 300 electrical injuries are recorded each year at the Swedish National Electrical Safety Board. Most of our knowledge of the health consequences of these arise from clinical case series. Severe electrical injuries have direct thermal effects and may result in ventricular fibrillation, skin burns, as well as muscular and nerve affection. Long-term consequences include pain, vascular symptoms, cognitive and neurological symptoms and signs. These sequelae may occur even though the initial symptoms were relatively modest. Mechanisms are better understood for the immediate symptoms, compared to long-term and delayed non-thermal medical consequences. Attention to and treatment of patients with electrical injury needs to be improved to minimize long-term consequences. Good medical care in the acute phase and early multidisciplinary follow-up of severe cases will likely reduce associated morbidity. Each electrical injury should result in an inquiry to identify the cause of the accident in order to suggest actions to prevent new incidents. |
21,065 | Optimal Implantable Cardioverter Defibrillator Programming. | Optimal programming of implantable cardioverter defibrillators (ICDs) is essential to appropriately treat ventricular tachyarrhythmias and to avoid unnecessary and inappropriate shocks. There have been a series of large clinical trials evaluating tailored programming of ICDs. We reviewed the clinical trials evaluating ICD therapies and detection, and the consensus statement on ICD programming. In doing so, we found that prolonged ICD detection times, higher rate cutoffs, and antitachycardia pacing (ATP) programming decreases inappropriate and painful therapies in a primary prevention population. The use of supraventricular tachyarrhythmia discriminators can also decrease inappropriate shocks. Tailored ICD programming using the knowledge gained from recent ICD trials can decrease inappropriate and unnecessary ICD therapies and decrease mortality. |
21,066 | The real world in the clinic before and after the establishment of guidelines for coronary artery spasm: a questionnaire for members of the Japanese Cine-angio Association. | We investigated the clinical situations and the present knowledge of Japanese cardiologists about coronary artery spasm before and after the establishment of guidelines for this condition in the real world. A questionnaire was developed regarding the number of cases of coronary angiography, percutaneous coronary intervention, and invasive/non-invasive spasm provocation tests before (2008) and after (2014) the establishment of the Japanese Circulation Society (JCS) guidelines for coronary artery spasm and the status of spasm provocation tests. The questionnaire was sent to members of the Japanese Cine-angio Association in 81 cardiology hospitals in Japan. The completed surveys were returned from 20 hospitals, giving a response rate of 24.7%. Pharmacological spasm provocation tests increased in 2014 and vasospastic angina and variant angina also increased in 2014 compared with 2008, but the increase was not significant. Non-invasive spasm provocation tests such as hyperventilation tests and cold stress tests decreased remarkably in 2014. Spasm provocation tests were initially performed in the left coronary artery was employed in just 30% of the hospitals. The majority of institutions did not perform the spasm provocation testing in patients with unknown causes of heart failure or in survivors of ventricular fibrillation. Although 40% of the hospitals were not satisfied with standard spasm provocation tests, the majority of the hospitals agreed that spasm provocation tests will be necessary in the future. In general, the JCS guidelines contributed to the widespread use of provocative testing for coronary artery spasm in the real world. However, some issues about spasm still remained in the clinic. |
21,067 | The association between defibrillation shock energy and acute cardiac damage in patients with implantable cardioverter defibrillators. | The aim of this study was to establish a minimally invasive defibrillation testing (DT) protocol for patients with implantable cardioverter defibrillators (ICDs).</AbstractText>Two different energy DTs were performed, immediately after (15 J-DT) and 7 days after (≤10 J-DT) device implantation, in 20 consecutive ICD implantation patients. Cardiac-troponin T (c-TNT) and heart-type fatty acid binding protein (H-FABP) levels were measured before implantation, 2 h after implantation, and 1 day after each DT. For an additional 122 patients with ICD, we retrospectively analyzed 203 DTs immediately and 7 days after device implantation.</AbstractText>Serum c-TNT levels were significantly elevated 2 h after 15 J-DT [0.008 (0.004-0.019) vs. 0.053 (0.037-0.068) ng/mL, p</i><0.001], but not ≤10 J-DT [0.007 (0.004-0.018) ng/mL]. Similarly, serum H-FABP levels were significantly elevated 2 h after 15 J-DT (2.9±1.5 vs. 6.4±3.4 ng/mL, p</i><0.001), but not ≤10 J-DT (2.7±1.5 ng/mL). The changes in c-TNT and H-FABP levels between baseline and 2 h after DT were significantly greater for 15 J-DT compared with ≤10 J-DT [c-TnT: 0.039 (0.029-0.060) vs. 0 (0-0.003) ng/mL, p</i><0.001; H-FABP: 3.6±2.8 vs. -0.16±1.1 ng/mL, p</i><0.001]. The success rates of the initial shocks delivered for ventricular fibrillation were no different between ≤10 J-DT (85% [78/92]) and ≥15 J-DT (92% [103/111]).</AbstractText>Elevated levels of myocardial damage markers such as c-TNT and H-FABP were not found after ≤10 J-DT. In addition, an acceptable success rate was confirmed in ≤10 J-DT.</AbstractText> |
21,068 | Impact of catheter ablation of ventricular tachycardia in patients with prior myocardial infarctions. | Catheter ablation can reduce episodes of ventricular tachycardia (VT) after myocardial infarction (MI). However, the optimal endpoint of the ablation procedure remains unclear.</AbstractText>Fifty-one consecutive patients who received catheter ablation for VT after MI were included. The procedures targeted the isthmus of all the induced, sustained VTs. When the patients with induced VTs were hemodynamically stable, radiofrequency energy was delivered at the mid-diastolic potential recording site during VT. When the patients with VTs were hemodynamically unstable, the critical channel was identified at the delayed potential recording site, showing a good pace map, with a long stimulus-QRS interval. We delivered radiofrequency energy along the identified isthmus and across the exit of the circuit.</AbstractText>At the end of the procedure, all VTs became non-inducible in 30 patients (59%) and some VTs were inducible in 21 patients (41%). During a mean of 40±29 months of follow-up, no VT or ventricular fibrillation recurred in 24 patients (80%) in the non-inducible group and in 12 patients (57%) in the inducible group, respectively (P</i>=0.03). The identification of the channel during VT mapping tended to associate with no recurrence, although the difference was not statistically significant (P</i>=0.2). Fourteen patients (27%) died during the follow-up period, mostly due to non-cardiac causes.</AbstractText>The catheter ablation targeting the isthmus of prior-MIVT and non-inducibility at the end of the procedure can provide a satisfactory follow-up result.</AbstractText> |
21,069 | Impact of Surgical Ablation of Atrial Fibrillation on the Progression of Tricuspid Regurgitation and Right-Sided Heart Remodeling After Mitral-Valve Surgery: A Propensity-Score Matching Analysis. | This study assessed the role of surgical ablation for atrial fibrillation (AF) in decreasing tricuspid regurgitation (TR) and right-sided heart remodeling in patients after mitral valve procedure.</AbstractText>Between 1994 and 2014, 1568 consecutive patients with AF undergoing mitral valve procedure were identified. In 26.0% (n=408), surgical ablation of AF was used. Propensity-score matching (PSM) was performed on the basis of 41 known perioperative risk variables. Survival, reoperation, stroke, and moderate-to-severe TR, as well as echocardiography indices in long-term follow-up, were compared in 406 matched patient pairs (ablated and nonablated groups). The nonablated group showed significantly higher risks of death (hazard ratio [HR], 1.644; 95% CI, 1.081-2.501; P=0.020), reoperation (HR, 2.644; 95% CI, 1.299-5.466; P=0.008), and moderate-to-severe TR (HR, 1.436; 95% CI, 1.059-1.948; P=0.020), associated with a significantly deteriorated cardiac function, progression of TR, and right-sided heart remodeling after 5-year follow-up. In a subgroup comparison of ablated patients with sinus rhythm versus AF recurrence, a PSM analysis was performed at the 5-year follow-up. The recurrent group showed significantly higher risks of moderate-to-severe TR (HR, 2.427; 95% CI, 1.261-4.671; P=0.008). AF recurrence was associated with progressive TR and significant deterioration in right-sided heart remodeling.</AbstractText>In a retrospective PSM analysis, mitral valve disease with AF was associated with TR progression as well as right-sided heart remodeling, which are alleviated by surgical ablation.</AbstractText>© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.</CopyrightInformation> |
21,070 | Diltiazem versus metoprolol for rate control in atrial fibrillation with rapid ventricular response in the emergency department. | The impact of patient-specific factors on the choice of β-blocker versus calcium channel blocker therapy for rate control in emergency department (ED) patients treated for atrial fibrillation (AF) was investigated.</AbstractText>A retrospective cohort study was conducted to evaluate the influence of demographics, prior medication use, hemodynamic and clinical characteristics, and other variables on selection of first-line therapy for AF among patients admitted to the ED of an academic medical center over a 22-month period (October 2012-July 2014) who received i.v. treatment with either the β-blocker metoprolol (n = 45) or the calcium channel blocker diltiazem (n = 55) for rate control.</AbstractText>Significant predictors of the selection of metoprolol versus diltiazem included a past history of AF (odds ratio [OR], 8.3; 95% confidence interval [CI], 1.396-72.713; p = 0.032) or diabetes mellitus (OR, 7.2; 95% CI, 1.208-58.490; p = 0.042) and being prescribed a β-blocker prior to presentation (OR, 27.8; 95% CI, 4.704-272.894; p = 0.001); a history of calcium channel blocker use prior to ED presentation was a negative predictor of β-blocker use for initial rate control (OR, 0.1; 95% CI, 0.005-0.265; p = 0.002). No differences in the effectiveness or safety of diltiazem and metoprolol were identified. Indicators of hemodynamic and clinical response to ED management were not predictive of discharge medication selection.</AbstractText>The drug class used for rate control prior to ED admission was the most significant predictor of medication selection for rate control in the ED setting.</AbstractText>Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.</CopyrightInformation> |
21,071 | Atrial conduction times and left atrial mechanical functions and their relation with diastolic function in prediabetic patients. | <AbstractText Label="BACKGROUND/AIMS" NlmCategory="OBJECTIVE">The aim of this study was to investigate atrial conduction times and left atrial mechanical functions, the noninvasive predictors of atrial fibrillation, in prediabetic patients with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT).</AbstractText>Study included 59 patients (23 males, 36 females; mean age 52.5 ± 10.6 years) diagnosed with IFG or IGT by the American Diabetes Association criteria, and 43 healthy adults (22 males, 21 females; mean age 48.5 ± 12.1 years). Conventional and tissue Doppler echocardiography were performed. The electromechanical delay parameters were measured from the onset of the P wave on the surface electrocardiogram to the onset of the atrial systolic wave on tissue Doppler imaging from septum, lateral, and right ventricular annuli. The left atrial volumes were calculated by the disk method. Left atrial mechanical functions were calculated.</AbstractText>The mitral E/A and E'/A' ratios measured from the lateral and septal annuli were significantly lower in the prediabetics compared to the controls. The interatrial and left atrial electromechanical delay were significantly longer in prediabetic group compared to the controls. Left atrial active emptying volume (LAAEV) and fraction (LAAEF) were significantly higher in the prediabetics than the controls. LAAEV and LAAEF were significantly correlated with E/A, lateral and septal E'/A'.</AbstractText>In the prediabetic patients, the atrial conduction times and P wave dispersion on surface electrocardiographic were longer before the development of overt diabetes. In addition, the left atrial mechanical functions were impaired secondary to a deterioration in the diastolic functions in the prediabetic patients.</AbstractText> |
21,072 | Left Ventricular Compressions Improve Hemodynamics in a Swine Model of Out-of-Hospital Cardiac Arrest. | We hypothesized that chest compressions located directly over the left ventricle (LV) would improve hemodynamics, including coronary perfusion pressure (CPP), and return of spontaneous circulation (ROSC) in a swine model of cardiac arrest.</AbstractText>Transthoracic echocardiography (echo) was used to mark the location of the aortic root and the center of the left ventricle on animals (n = 26) which were randomized to receive chest compressions in one of the two locations. After a period of ten minutes of ventricular fibrillation, basic life support (BLS) with mechanical cardiopulmonary resuscitation (CPR) was initiated and performed for ten minutes followed by advanced cardiac life support (ACLS) for an additional ten minutes. During BLS the area of maximal compression was verified using transesophageal echo. CPP and other hemodynamic variables were averaged every two minutes.</AbstractText>Mean CPP was not significantly higher in the LV group during all time intervals of resuscitation; mean CPP was significantly higher in the LV group during the 12-14 minute interval of BLS and during minutes 22-30 of ACLS (p < 0.05). Aortic systolic and diastolic pressures, right atrial systolic pressures, and end-tidal CO2 (ETCO2) were higher in the LV group during all time intervals of resuscitation (p < 0.05). Nine of the left ventricle group (69%) achieved ROSC and survived to 60 minutes compared to zero of the aortic root group (p < 0.001).</AbstractText>In our swine model of cardiac arrest, chest compressions over the left ventricle improved hemodynamics and resulted in a greater proportion of animals with ROSC and survival to 60 minutes.</AbstractText> |
21,073 | Galectin-3: A biochemical marker to detect paroxysmal atrial fibrillation? | Atrial fibrillation (AF) is the most common form of arrhythmia. AF leads to electrical remodelling and fibrosis of the atria; however, the mechanism(s) remain poorly understood. Galectin-3 is a potential mediator of cardiac fibrosis. The present study aimed to examine the relationship between serum galectin-3 levels and paroxysmal AF.</AbstractText>Forty-six patients with paroxysmal AF and preserved left ventricular systolic function, and 38 age- and gender-matched control subjects, were involved in the study. Serum galectin-3 levels were analyzed with an enzyme-linked immunosorbent assay (ELISA).</AbstractText>Serum galectin-3 levels (median 1.38 ng/mL; 1.21 ng/mL-1.87 ng/mL; p< 0.001) were significantly elevated in patients with paroxysmal AF compared with the control. Left atrial diameter was significantly higher in patients with paroxysmal AF (41.2±3.0 mm vs. 39.6±3.3 mm). Left atrial diameter was found to be significantly correlated with serum galectin-3 levels in patients with paroxysmal AF (r= 0.378, p= 0.001).</AbstractText>Serum galectin-3 levels are significantly elevated and significantly correlated with left atrial diameter in patients with paroxysmal AF.</AbstractText> |
21,074 | Synthesis and Structure-Activity Relationships of a Series of Aporphine Derivatives with Antiarrhythmic Activities and Acute Toxicity. | Some aporphine alkaloids, such as crebanine, were found to present arrhythmic activity and also higher toxicity. A series of derivatives were synthesized by using three kinds of aporphine alkaloids (crebanine, isocorydine, and stephanine) as lead compounds. Chemical methods, including ring-opening reaction, bromination, methylation, acetylation, quaternization, and dehydrogenation, were adopted. Nineteen target derivatives were evaluated for their antiarrhythmic potential in the mouse model of ventricular fibrillation (VF), induced by CHCl₃, and five of the derivatives were investigated further in the rat model of arrhythmia, induced by BaCl₂. Meanwhile, preliminary structure-activity/toxicity relationship analyses were carried out. Significantly, <i>N</i>-acetamidesecocrebanine (<b>1d</b>), three bromo-substituted products of crebanine (<b>2a</b>, <b>2b</b>, <b>2c</b>), <i>N</i>-methylcrebanine (<b>2d</b>), and dehydrostephanine (<b>4a</b>) displayed antiarrhythmic effects in the CHCl₃-induced model. Among them, 7.5 mg/kg of <b>2b</b> was able to significantly reduce the incidence of VF induced by CHCl₃ (<i>p</i> < 0.05), increase the number of rats that resumed sinus rhythm from arrhythmia, induced by BaCl₂ (<i>p</i> < 0.01), and the number of rats that maintained sinus rhythm for more than 20 min (<i>p</i> < 0.01). Therefore, <b>2b</b> showed remarkably higher antiarrhythmic activity and a lower toxicity (LD<sub>50</sub> = 59.62 mg/kg, mice), simultaneously, indicating that <b>2b</b> could be considered as a promising candidate in the treatment of arrhythmia. Structural-activity analysis suggested that variationsin antiarrhythmic efficacy and toxicity of aporphines were related to the C-1,C-2-methylenedioxy group on ring A, restricted ring B structural conformation, <i>N</i>-quaternization of ring B, levoduction of 6a in ring C, and the 8-, 9-, 10-methoxy groups on ring D on the skeleton. |
21,075 | Predictive Value of QRS Duration at Admission for In-Hospital Clinical Outcome of Takotsubo Cardiomyopathy. | Prolonged QRS duration (pQRSd) on electrocardiogram (ECG) is a strong predictor of poor outcome in heart failure, myocardial infarction, and myocarditis, but it is unclear whether pQRSd also predicts poor outcomes of takotsubo cardiomyopathy (TC).Methods and Results:Between 1 January 2010 and 31 December 2012, we retrospectively enrolled 299 patients with TC (mean age, 73.5±11.7 years; 21.4% male) from the Tokyo CCU Network database, which consists of 71 cardiovascular centers in the metropolitan area. In-hospital clinical outcomes were compared between patients with pQRSd on admission ECG (QRS ≥120 ms; n=34) and those with normal QRS duration (<120 ms; n=265). The in-hospital mortality rate for pQRSd was significantly higher than that for normal QRS duration (23.5% vs. 3.8%, P<0.001). Similarly, prevalence of ventilator use (38.2% vs. 11.4%, P<0.001), ventricular tachycardia or fibrillation (14.7% vs. 1.5%, P<0.001), and circulatory failure requiring catecholamine or cardiopulmonary supportive devices (41.2% vs. 14.0%, P<0.001) was significantly higher in the pQRSd group. On multivariate logistic regression analysis, pQRSd was an independent predictor for both in-hospital mortality (OR, 5.06; 95% CI: 1.79-14.30, P=0.002) and cardiac death (OR, 7.34; 95% CI: 1.33-40.51, P=0.02).</AbstractText>TC with pQRSd is associated with poor in-hospital clinical outcome. Aggressive intervention may be required to prevent severe complications in these patients.</AbstractText> |
21,076 | A Novel Mechanism for Human Cardiac Ankyrin-B Syndrome due to Reciprocal Chromosomal Translocation. | Cardiac rhythm abnormalities are a leading cause of morbidity and mortality in developed countries. Loss-of-function variants in the ANK2 gene can cause a variety of cardiac rhythm abnormalities including sinus node dysfunction, atrial fibrillation and ventricular arrhythmias (called the "ankyrin-B syndrome"). ANK2 encodes ankyrin-B, a molecule critical for the membrane targeting of key cardiac ion channels, transporters, and signalling proteins.</AbstractText>Here, we describe a family with a reciprocal chromosomal translocation between chromosomes 4q25 and 9q26 that transects the ANK2 gene on chromosome 4 resulting in loss-of-function of ankyrin-B. Select family members with ankyrin-B haploinsufficiency due to the translocation displayed clinical features of ankyrin-B syndrome. Furthermore, evaluation of primary lymphoblasts from a carrier of the translocation showed altered levels of ankyrin-B as well as a reduced expression of downstream ankyrin-binding partners.</AbstractText>Thus, our data conclude that, similar to previously described ANK2 loss-of-function "point mutations", large chromosomal translocations resulting in ANK2 haploinsufficiency are sufficient to cause the human cardiac ankyrin-B syndrome. The unexpected ascertainment of ANK2 dysfunction via the discovery of a chromosomal translocation in this family, the determination of the familial phenotype, as well as the complexities in formulating screening and treatment strategies are discussed.</AbstractText>Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). All rights reserved.</CopyrightInformation> |
21,077 | Levosimendan in patients with left ventricular systolic dysfunction undergoing cardiac surgery on cardiopulmonary bypass: Rationale and study design of the Levosimendan in Patients with Left Ventricular Systolic Dysfunction Undergoing Cardiac Surgery Requiring Cardiopulmonary Bypass (LEVO-CTS) trial. | Low cardiac output syndrome is associated with increased mortality and occurs in 3% to 14% of patients undergoing cardiac surgery on cardiopulmonary bypass (CPB). Levosimendan, a novel calcium sensitizer and KATP</sub> channel activator with inotropic, vasodilatory, and cardioprotective properties, has shown significant promise in reducing the incidence of low cardiac output syndrome and related adverse outcomes in patients undergoing cardiac surgery on CPB.</AbstractText>LEVO-CTS is a phase 3 randomized, controlled, multicenter study evaluating the efficacy, safety, and cost-effectiveness of levosimendan in reducing morbidity and mortality in high-risk patients with reduced left ventricular ejection fraction (≤35%) undergoing cardiac surgery on CPB. Patients will be randomly assigned to receive either intravenous levosimendan (0.2 μg kg-1</sup> min-1</sup> for the first hour followed by 0.1 μg/kg for 23hours) or matching placebo initiated within 8hours of surgery. The co-primary end points are (1) the composite of death or renal replacement therapy through day 30 or perioperative myocardial infarction, or mechanical assist device use through day 5 (quad end point tested at α<.01), and (2) the composite of death through postoperative day 30 or mechanical assist device use through day 5 (dual end point tested at α<.04). Safety end points include new atrial fibrillation and death through 90days. In addition, an economic analysis will address the cost-effectiveness of levosimendan compared with placebo in high-risk patients undergoing cardiac surgery on CPB. Approximately 880 patients will be enrolled at approximately 60 sites in the United States and Canada between July 2014 and September 2016, with results anticipated in January 2017.</AbstractText>LEVO-CTS, a large randomized multicenter clinical trial, will evaluate the efficacy, safety, and cost-effectiveness of levosimendan in reducing adverse outcomes in high-risk patients undergoing cardiac surgery on CPB.</AbstractText>ClinicalTrials.gov (NCT02025621).</AbstractText>Copyright © 2016 Elsevier Inc. All rights reserved.</CopyrightInformation> |
21,078 | Extracorporeal membrane oxygenation in transcatheter aortic valve replacement. | Background Patients undergoing transcatheter aortic valve replacement can experience severe perioperative complications leading to hemodynamic instability and death. Venoarterial extracorporeal membrane oxygenation can be used to provide cardiorespiratory support during this time. Methods From 2012 to 2015, of 247 patients who underwent transcatheter aortic valve replacement, 6 (2.42%) required extracorporeal membrane oxygenation support. Their mean age was 82 ± 7.4 years, mean Society of Thoracic Surgeons score was 9.4 ± 6.6, and mean aortic gradient was 28.3 ± 12 mm Hg. Rescue extracorporeal membrane oxygenation was required for hemodynamic instability due to ventricular fibrillation ( n = 1), respiratory failure ( n = 1), left ventricular wall rupture ( n = 2), and aortic annulus rupture ( n = 1). In one patient, prophylactic extracorporeal membrane oxygenation was required due to advanced heart failure. Additional procedures included valve-in-valve implantation ( n = 1), conversion to an open procedure ( n = 3), and intraaortic balloon pump insertion ( n = 1). Results The median hospital stay was 20 days. There were 2 hospital deaths in patients whose hospital course was complicated by left ventricular wall rupture or aortic annulus rupture with resulting tamponade. Among the 4 survivors, one required continuous ventilator support following discharge, and 3 experienced no major complications during the first month after discharge. Conclusions Extracorporeal membrane oxygenation can be considered a viable option for high-risk patients undergoing transcatheter aortic valve replacement and those who develop cardiac complications following this procedure and require cardiorespiratory support. |
21,079 | CHA<sub>2</sub>DS<sub>2</sub>-VASc Scores and Major Bleeding in Patients With Nonvalvular Atrial Fibrillation Who Are Receiving Rivaroxaban. | Assessing stroke risk associated with nonvalvular atrial fibrillation depends on the evaluation of patient characteristics and clinical features. Clinicians must determine that the net clinical benefit from anticoagulation therapy outweighs its risk, namely, bleeding. Risk assessment for stroke is commonly performed by calculating a CHA2</sub>DS2</sub>-VASc (congestive heart failure/left ventricular dysfunction, hypertension, ≥75 years, diabetes mellitus, previous stroke or transient ischemic attack or thromboembolism, vascular disease, aged 65 to 74 years, sex female) score. It is possible that CHA2</sub>DS2</sub>-VASc scores also have a relationship with the incidence of major bleeding. We examined the relationship between CHA2</sub>DS2</sub>-VASc scores and major bleeding in rivaroxaban users with nonvalvular atrial fibrillation.</AbstractText>Electronic medical records of more than 10 million patients from the Department of Defense Military Health System were queried to identify patients with nonvalvular atrial fibrillation who received rivaroxaban from January 1, 2013, to June 30, 2015. Baseline characteristics of the study population were described by CHA2</sub>DS2</sub>-VASc scores and major bleeding status; major bleeding incidence was evaluated by CHA2</sub>DS2</sub>-VASc score category and for each CHA2</sub>DS2</sub>-VASc component.</AbstractText>Overall, 44,793 patients met the inclusion criteria for this analysis. The major bleeding incidence rate was 2.84 (95% confidence interval 2.69 to 3.00) per 100 person-years. The incidence of major bleeding increased from 0.30 to 5.40 per 100 person-years among patients with a CHA2</sub>DS2</sub>-VASc score of 0 to 5 or higher, respectively. Fatal outcomes among patients with major bleeding were positively correlated with CHA2</sub>DS2</sub>-VASc scores; patients with higher scores had higher mortality rates. The CHA2</sub>DS2</sub>-VASc component with the highest major bleeding incidence was for vascular disease, 5.69 (95% confidence interval 5.18 to 6.24) per 100 person-years.</AbstractText>Higher CHA2</sub>DS2</sub>-VASc scores are associated with increased incidence of major bleeding in nonvalvular atrial fibrillation patients receiving rivaroxaban.</AbstractText>Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
21,080 | Hypertrophic obstructive cardiomyopathy. | Hypertrophic obstructive cardiomyopathy is an inherited myocardial disease defined by cardiac hypertrophy (wall thickness ≥15 mm) that is not explained by abnormal loading conditions, and left ventricular obstruction greater than or equal to 30 mm Hg. Typical symptoms include dyspnoea, chest pain, palpitations, and syncope. The diagnosis is usually suspected on clinical examination and confirmed by imaging. Some patients are at increased risk of sudden cardiac death, heart failure, and atrial fibrillation. Patients with an increased risk of sudden cardiac death undergo cardioverter-defibrillator implantation; in patients with severe symptoms related to ventricular obstruction, septal reduction therapy (myectomy or alcohol septal ablation) is recommended. Life-long anticoagulation is indicated after the first episode of atrial fibrillation. |
21,081 | Gene Therapy for Post-infarction Ventricular Tachycardia. | Cardiac arrhythmias are a leading cause of morbidity and mortality in the developed world. In particular, cardiac arrest or sudden cardiac death is the leading cause of death in these countries. Death generally results from a ventricular tachyarrhythmia, and pathology data have shown that cardiac arrest victims very frequently have evidence of coronary atherosclerosis with either acute ischemia or healed myocardial infarction. In this work, we describe an animal model that reproducibly has inducible ventricular tachyarrhythmias after healing of a myocardial infarction scar and a gene delivery method that allows gene transfer to the scar and surrounding myocardial tissues. Use of the method allows gene delivery to the arrhythmia model for testing of hypotheses related to ventricular tachyarrhythmia mechanisms and for efficacy testing of proposed gene therapies. To date, all work in this area has been preclinical, but it is our hope that continued development in this area will 1 day allow translation of this method into clinical practice. |
21,082 | A Meta-Analysis Of Quadripolar Versus Bipolar Left Ventricular Leads On Post-Procedural Outcomes. | <b>Objective:</b> We aimed to perform a meta-analysis from eligible studies to analyze the true impact of QL when compared with BL with regard to post-procedural outcomes including lead deactivation, revision or replacement. <b>Background:</b> Many observational and retrospective studies showed that quadripolar left ventricular leads (QL) are associated with better outcomes and fewer complications when compared with bipolar leads (BL). <b>Methods:</b> We performed a comprehensive literature search through June 30, 2015 using: quadripolar, bipolar, left ventricular lead and CRT in Pubmed, Ebsco and google scholar databases. <b>Results:</b> The analysis included 8 studies comparing QL and BL implantation. Post-procedural outcomes such as lead deactivation, revision or replacement were used as primary outcome and assessed with Mantel-Haenszel risk ratio (RR). Secondary outcomes included total fluoroscopy/procedure time, occurrence of phrenic nerve stimulation (PNS) and all-cause mortality on follow up. Follow-up duration for the studies ranged from 3 to 60 months. Compared with BL, the use of QL is associated with 52 % reduction (relative risk 0.48; 95% CI: 0.36-0.64, p=0.00001) in the risk of deactivation, revision or replacement of the LV lead. QL had significantly lower fluoroscopy/procedure time, PNS and all-cause mortality when compared with BL. <b>Conclusion:</b>Our meta-analysis shows that QL implantation was associated with decreased risk of LV lead deactivation, revision or replacement when compared with BL. |
21,083 | Right Ventricular Pacing for Assessment of Cavo-Tricuspid Isthmus Block. | <b>Background:</b> Cavo-tricuspid isthmus (CTI) dependent atrial flutter is typically treated with cardiac ablation. Standard techniques to assess CTI block after ablation can be technically challenging. Right ventricular (RV) pacing may allow for another technique to assess CTI block after ablation. <b>Objective:</b> The purpose of this study was to evaluate RV pacing as a method to assess CTI block after ablation of CTI dependent atrial flutter, and define endpoints of ablation using this technique. <b>Methods:</b> 28 patients undergoing ablation of CTI dependent atrial flutter with intact ventriculoatrial (VA) conduction were prospectively enrolled in this study and underwent the RV pacing protocol, as well as standard coronary sinus (CS) pacing techniques to assess CTI block. <b>Results:</b> The mean trans-isthmus conduction interval during CS pacing (TICI<sub>CS</sub>) at 600 and 400ms after CTI ablation was 168 +/- 9ms and 175 +/- 18ms, respectively. The mean trans-isthmus conduction interval during RV pacing (TICI<sub>RV</sub>) at 600ms and 400ms after CTI ablation was 109 +/- 5ms and 111 +/- 5ms, respectively. A TICI<sub>RV</sub> >100ms was associated with a successful outcome after CTI ablation. <b>Conclusions:</b> RV pacing may add incremental value in the assessment of CTI block in patients undergoing ablation of CTI dependent atrial flutter. |
21,084 | Efficacy And Safety Of Implantable Loop Recorder: Experience Of A Center. | <b>Introduction:</b> Symptoms like syncope or palpitations frequently present a diagnostic challenge. An implantable loop recorder (ILR) is an important aid in the management of these patients. <b>Methods:</b> A retrospective study of patients that underwent ILR implantation from November 2007 to 2014. For each patient the indication for implantation, baseline characteristics, previous study, complications, recorded tracing and interventions were evaluated. <b>Results:</b> A total of 62 patients were included, 50% men, with a mean age of 62.5±18.8 years old. Previously to ILR implantation 88.7% of patients had performed Holter, 17.7% external events recorder, 33.9% Tilt test and 29% an electrophysiological study. The implantation indications were recurrent syncope in 90.3%, palpitations 8.1% and ischemic stroke in one patient. Mean follow-up time was 17.1±16.3 months. Symptoms were reported in 66.1% of the patients, 46.8% of those yielding a diagnostic finding. In all cases of palpitation complaints with diagnosis we found atrial fibrillation (AF). In patients with syncope atrioventricular conduction disturbance was demonstrated in 19.6%, sinus node dysfunction in 16.1%, paroxysmal supra-ventricular tachycardia 7.1% and AF in 1.8%. These finding resulted in 19 pacemaker and one CRT-D implantation, introduction of anticoagulation in five patients and one ablation of accessory pathway. There were no major complications. <b>Conclusion:</b> ILR proved to be safe and efficient. It has enabled the identification or exclusion of serious rhythm disturbances in more than half of patients and provided a targeted therapeutic intervention. |
21,085 | Patient Specific Induced Pluripotent Stem Cell-Derived Cardiomyocytes for Drug Development and Screening In Catecholaminergic Polymorphic Ventricular Tachycardia. | Catecholaminergic polymorphic ventricular tachycardia (CPVT), an inherited arrhythmia often leading to sudden cardiac death in children and young adults, is characterized by polymorphic/bidirectional ventricular tachycardia induced by adrenergic stimulation associated with emotionally stress or physical exercise. There are two forms of CPVT: 1. CPVT1 is caused by mutations in the RYR2 gene, encoding for ryanodine receptor type 2. CPVT1 is the most common form of CPVT in the population, and is inherited by a dominant mechanism. 2. CPVT2 is caused by mutations in the CASQ2 gene, encoding for cardiac calsequestrin 2 and is inherited by recessive mechanism. Patient-specific induced Pluripotent Stem Cells (iPSC) have the ability to differentiate into cardiomyocytes carrying the patient's genome including CPVT-linked mutations and expressing the disease phenotype in vitro at the cellular level. The potency for in vitro modeling using iPSC-derived cardiomyocytes (iPSC-CMs) has been exploited to investigate a variety of inherited diseases including cardiac arrhythmias such as CPVT. In this review we attempted to cover the majority of CPVT patient specific iPSC research studies previously published. CPVT patient-specific iPSC model enables the in vitro investigation of the molecular and cellular disease-mechanisms by the means of electrophysiologycal and Ca<sup>+2</sup> imaging methodologies. Furthermore, this in vitro model allows the screening of various antiarrhythmic drugs, specifically for each patient, also known as "personalized medicine". |
21,086 | Ajmaline Challenge To Unmask Infrahisian Disease In Patients With Recurrent And Unexplained Syncope, Preserved Ejection Fraction, With Or Without Conduction Abnormalities On Surface ECG. | <b>Background:</b> Pharmacological challenge with class I antiarrhythmic drug is a recommended diagnostic test in patients with unexplained syncope only in the presence of bundle branch block, when non-invasive tests have failed to make the diagnosis. Its role in patients with minor or no conduction disturbances on 12-leads ECG has not been evaluated yet. It is also not clear which are the values of His-Ventricular interval to be considered diagnostic. We sought to evaluate the role of ajmaline challenge in unmasking the presence of an infrahisian disease in patients with recurrent and unexplained syncope, regardless of the existence of conduction disturbances on surface ECG. <b>Materials And Methods:</b> Patients with history of recurrent syncope, preserved EF and a negative first level workup were enrolled. Conduction disturbances on ECG were not considered as an exclusion criteria. During EPS, basal HV conduction was determined. In the presence of a HV >70 msec the study was interrupted and the patient was implanted with a pacemaker. If the HV was ≤ 70 msec, ajmaline was infused and HV was reassessed. The maximum value of HV was considered. A prolongation ≥ 100 msec was considered as diagnostic and indicative of conduction disease, and the patient underwent pacemaker implantation. Patients with an HV <100 msec were implanted with an ILR. <b>Results:</b> Sixteen consecutive patients were studied (age 76±5.2 years). Nine patients had conduction disturbances at baseline ECG (group ECG+). Among them, 5 had a basal diagnostic HV interval and 4 had a non-diagnostic HV interval. In the latter group, abnormal response to ajmaline was observed in 3 patients. In this group only one patient was implanted with an ILR, 8 patients were implanted with a pacemaker. Among the seven patients without conduction disturbances (group ECG-), no one had a diagnostic basal HV interval. After drug administration, 4 patients had a non-diagnostic response and were implanted with an ILR, while 3 patient had a pathological response and were implanted with a pacemaker. No difference was found in the values of maximum HV interval prolongation after ajmaline between the two groups (P = 0.89). During a mean follow up of 13±3 months, no patient has developed a syncopal episode. One patient in group ECG- and negative drug test was implanted after 3 months with a permanent pacemaker because of a two to one asymptomatic AV block at ILR interrogation. <b>Conclusions:</b> Ajmaline challenge is a useful tool to unmask the presence of a infrahisian disease in patients with preserved EF, unexplained syncope and negative workup, even in the absence of conduction disturbances on 12-leads ECG. It is a simple and safe test that may disclose the detection of the disease. In these patients, an earlier pacemaker implantation of a pacemaker, may avoid the consequences of a syncopal recurrence. Values of HV interval > 70 msec in basal conditions and ≥ 100 msec after ajmaline administration seem appropriate to unmask infrahisian disease. Larger population is required to validate this hypothesis. |
21,087 | Emergency Department Readmission in Elderly Patients After Acute Rhythm or Rate Control Treatment for Atrial Fibrillation. | Atrial fibrillation (AF) is an age-related increasing disease, characterized by a high number of relapses frequently leading the patients to Emergency Department (ED). Despite AF relapses may be clinically heterogeneous, a proper management requires either a fast and effective restore of the sinus rhythm or a satisfactory control of the ventricular rate. Whether the strategy adopted in the ED could affect the course of disease is still debated. Therefore, the aim of our study was to evaluate the number of ED readmission for AF related symptoms and the event-free period in patients older than 70 years previously treated in ED for an AF recurrence, in order to assess a possible relationship with the acute strategy. An overall number of 302 recurrences of AF were drawn randomly, regarding 102 patients (mean age 78 years). We found that 206 cases (68.2%) were treated with rhythm restoration strategy (RR) whereas 96 (31.8%) with rate control strategy (RC). The median following event-free period was 118.6 +/- 15.5 and 212.9 +/- 37.1 days (p < 0.05) for RR and RC strategy, respectively. Within 6 months, 124 (60.1%) out of RR group patients and only 44 (45.8%) out of RC group patients had to be readmitted to ED for AF related symptoms (whether a recurrence or inefficient rate control symptoms) (p< 0.05). This advantage was substantially confirmed (79.1% vs 65.6% respectively, p < 0.05) after a 12 months follow-up. Our results indicate that acute treatment of AF may affect the long-term outcome of the disease and the ED readmission rate of the patient. Ventricular rate control seems to be associated with a longer event-free period if compared to the rhythm control strategy in the elderly patients. This suggests an age-based work-up of patients admitted to the ED, preferentially using ventricular rate control in elderly subjects. |
21,088 | Comparison of the Influence of Right Atrial Septal Pacing and Appendage Pacing on an Atrial Function and Atrial Fibrillation in the Clinical Situation. | Recently right atrial septal (RAS) pacing is often selected, but the benefit brought by RAS pacing has not been clear. The aim of this study was to evaluate the differences between RAS pacing and right appendage (RAA) pacing.</AbstractText>223 consecutive new patients with a right atrial (RA) electrode during the period from January 2004 to December 2012 were studied retrospectively. They were observed regularly at our pacemaker (PM) clinic, and we measured paced P - sensed QRS interval (pPQi) and left atrial dimension (LAD) during the observation period, furthermore the onset of atrial fibrillation (AF) was assessed.</AbstractText>Mean age was 74.5 years and 104 were men. Mean follow-up period was 4.5 years. 177 patients received RAA pacing and 46 received RAS pacing. There was no difference of LAD and pPQi between patients with RAA pacing and with RAS pacing with more than 50% of percentage as the atrial pacing (%AP). About the comparison between intrinsic PQ interval and pPQi, only RAA pacing made long significantly from intrinsic PQ interval to pPQi (p=0.020, 172.3±46.3 vs. 189.7±38.0). The %AP more than 50% brought less probability of the onset AF. On the other hand, none of pacing sites of RA, pacing mode, and the percentage of ventricular pacing influenced on the probability of the onset of AF. Although in patients with 50% as %AP RAA pacing made patients with AF increased (from 17 to 22), RAS pacing made them decreased (from 14 to 12).</AbstractText>This study did not show the superiority of RAS pacing to RAA pacing, it seems that %AP is more important for the onset of AF. The possibility was seen that RAS pacing reduces the onset of AF.</AbstractText> |
21,089 | Clinical Use And Limitations Of Non-Invasive Electrophysiological Tests In Patients With Atrial Fibrillation. | Atrial fibrillation (AF) is a complex arrhythmia, that has been studied non-invasively assessing atrial refractory period, atrioventricular node (AV) node refractory period, and ventricular response. The AV node plays a fundamental role as it filters many of the numerous irregular atrial impulses bombarding the node. Despite its importance, the electrophysiological (EP) characteristics of the AV node are not routinely evaluated since conventional EP techniques for assessment of refractory period or conduction velocity of the AV node are not applicable in AF. Since rate-control drugs control ventricular response through their effect on the AV node, noninvasive assessment of AV node electrophysiology may be useful. The RR series, though being highly irregular, contains information that can be used for risk stratification and prediction of outcome. In particular, RR irregularity measures during AF have been shown to be related to clinical outcome. This paper reviews the attempts done to noninvasively characterize the AV node and the ventricular response, highlighting clinical applications and limitations of the noninvasive techniques. |
21,090 | Myocardial Biopsy In "Idiopathic» Atrial Fibrillation And Other Arrhythmias: Nosological Diagnosis, Clinical And Morphological Parallels, And Treatment. | The nosological nature of "idiopathic" arrhythmias and the effect of etiotropic and pathogenetic treatment are often unknown.</AbstractText>19 patients (42.6±11.3 years, 9 women) with atrial fibrillation (n = 16), supraventricular (n = 10) and ventricular (n = 4) premature beats, supraventricular (n = 2) and ventricular tachycardia (n = 1), left bundle branch block (n= 2), AV block (n = 2) without structural heart changes. Viruses were identified (polymerase chain reaction, PCR) along with measurement of anti-heart antibodies (AHA) and endomyocardial biopsy (EMB). EMB allowed to establish diagnosis in all patients: infectious-immune myocarditis (n = 11, parvovirus-positive in 1),parvovirus-positive endomyocarditis (n = 1),systemic (n = 2) and myocardial (n = 1) vasculitis,Fabry's disease (n = 1), arrhythmogenic right ventricular dysplasia (n = 1),unspecified genetic cardiomyopathy (n = 2, herpes virus 6 one positive). Level of AHA had the greatest significance for myocarditis diagnostics. All patients with myocarditis/vasculitis had background therapy: acyclovir (n = 10), IV immunoglobulin (n = 2), meloxicam (n = 12), hydroxychloroquine (n = 15), steroids (n = 14, 31.1±12.5 mg/day), azathioprine 150 mg/day (n = 2). Median follow-up was 4 years. Treatment significantly reduced the rate of arrhythmias (8 [5;8] to 3 [1.25;7.75] points); disappearance of bundle branch block was noted.</AbstractText>EMB allowed to diagnose immune-mediated inflammatory diseases in 78.9% patients with 'idiopathic' arrhythmias and genetic diseases in 21.1%. Background therapy of myocarditis improved the antiarrhythmic efficiency, and allowed the best premed for interventional treatment.</AbstractText> |
21,091 | Cardiac Rhythm Device Threshold Testing Via Pulse Oxymetry. | Threshold testing of cardiac rhythm devices is essential to monitoring the proper functioning of such devices (1). However, the currently method of applying multiple ECG leads to the patient is burdensome and time consuming (2). We are presenting a completely new way to perform cardiac rhythm device threshold testing using pulse oximetry. Twenty patients, with varying cardiac rhythm devices and pacing modes, were enrolled and had their atrial and ventricular thresholds tested. A comparison was made between simultaneous threshold determinations via the standard EGM based method and the new pulse oximetry based method. 75% of the ventricular threshold tested and 58% of the atrial thresholds tested were the same with the two testing methods. The remainder of the tests (25% of ventricular threshold and 42% of the atrial threshold tests) varied by +0.25 V. This study shows that pulse oximetry based testing is an accurate, reliable, and easy way to perform cardiac rhythm device threshold testing and may complement traditional methods to perform such tests in the future. |
21,092 | Hyperacute And Chronic Changes In Cerebral Magnetic Resonance Images After Pvac, nmarq And Epicardial Thoracoscopic Surgical Ablation For Paroxysmal Atrial Fibrillation. | Threshold testing of cardiac rhythm devices is essential to monitoring the proper functioning of such devices (1). However, the currently method of applying multiple ECG leads to the patient is burdensome and time consuming (2). We are presenting a completely new way to perform cardiac rhythm device threshold testing using pulse oximetry. Twenty patients, with varying cardiac rhythm devices and pacing modes, were enrolled and had their atrial and ventricular thresholds tested. A comparison was made between simultaneous threshold determinations via the standard EGM based method and the new pulse oximetry based method. 75% of the ventricular threshold tested and 58% of the atrial thresholds tested were the same with the two testing methods. The remainder of the tests (25% of ventricular threshold and 42% of the atrial threshold tests) varied by +0.25 V. This study shows that pulse oximetry based testing is an accurate, reliable, and easy way to perform cardiac rhythm device threshold testing and may complement traditional methods to perform such tests in the future. |
21,093 | Shock Lead Dislodgement Related To Its Small Hair-Pin Curve In A Pocket -A Case Of Ratchet Syndrome. | There have been few reports about ratchet syndrome. We report a case of ratchet syndrome caused by small hair-pin curve of lead that triggered the lead retract itself. A 69-year-old man with a past history of inferior wall myocardial infarction, presented with progressive congestive heart failure. He underwent implantation of cardiac resynchronization therapy with an implantable cardiac defibrillator (CRTD) at our hospital. At 33 days after implantation, shock lead dislodgement was revealed. X-ray showed that the lead tip was in left subclavian vein, leaving its screw out, and a large part of the proximal portion of the lead was retracted into the pocket, while the other two leads remained in appropriate positions and the device had not rotated. An X-ray series showed that a hair-pin curve had been expanding gradually from just after implantation. In this case, relatively stiff shock lead was markedly bent and expanded the curve in the pocket, and ratchet-like movement occurred. We here report a new type of ratchet syndrome. |
21,094 | Persistent Atrial Fibrillation And Atrial Flutter Complicated By Tachycardiomyopathy Because Of Intermittent Conduction Through Accessory Pathway. | The term tachycardiomyopathy refers to a specific form of tachycardia-related cardiomyopathy caused by supraventricular or ventricular tachyarrhytmias that are both associated with ventricular rates higher than 120 bpm. The arrhythmias which are most frequently associated with these forms of heart disease are atrial fibrillation and atrial flutter, particularly found in the elderly population. The most frequent clinical manifestation is heart failure. In this case we are reporting a clinical case of a patient that came to our attention because of an episode of heart failure associated with atrial fibrillation and atrial flutter. The patient had also prolonged and repetitive strips of rapid conduction with wide QRS morphology. We don't know if the cause is pre excitation or ectopia. We showed that those strips of tachycardia with wide QRS, particularly when they were associated with atrial flutter, were so fast and consistent to determine the left ventricular contractile dysfunction; we showed also that those strips of wide complex tachycardia were caused by pre-excitation through an accessory right posteroseptal pathway and supported by the reentry circuit of common atrial flutter. The block of conduction through the accessory pathway and the elimination of atrial arrhythmia allowed the regression of left ventricular contractile dysfunction. We believe that this case is interesting because it shows that there is a strict continuity between sophisticated electrophysiological mechanisms and clinical manifestation. |
21,095 | The Wearable Cardioverter/Defibrillator - Toy Or Tool? | After the success story of implantable cardioverter/defibrillator systems, prevention of sudden cardiac death (SCD) remains one of the main duties in cardiology. For patients with unkown or transient risk profile for SCD, a wearable cardioverter/defibrillator (WCD) has been established for temporary and effective prevention of sudden arrhythmic death. Several studies have shown safety and efficacy of the WCD, even though randomized studies proving a mortality benefit are still lacking. This review provides an overview of actual WCD data and usage, special indications and possible risks and complications. WCD use is effective and adequate for temporary prevention of SCD in chosen populations. In particular, it provides secured time for sophisticated risk stratification to identify patients at persistent risk for SCD. Nevertheless, prospective randomized trials seem mandatory to prove a prognostic relevance and the economic value of this device. |
21,096 | Idiopathic VPC: Distribution Of FOCI And Tips Of Ablation. | Idiopathic Ventricular Premature Contraction (VPC) is currently more routinely referred for electrophysiology evaluation. Usually it carries a good prognosis but, when symptomatic or suspected to produce ventricular dysfunction, will require treatment. Nowadays, RF ablation has great advantages over antiarrhythmic drugs. Classically the outflow tract (right or left), with the typical inferior axis with left (eventually right) bundle brunch block like ECG morphology, is considered the most frequent site of origin for idiopathic VPC, but with the widespread of EP procedures and advancement of technology making possible to map and ablate difficult locations, it is possible to see a growing and changing population referred for idiopathic VPC ablation, displaying that, almost any region of the heart may be source of this kind of arrhythmia that can be successfully treated. A well-planned procedure, with the presumed region of origin settled and employing the current technology and knowledge (tips), will have a high chance of cure. |
21,097 | Supraventricular Tachycardia with Irregular Ventricular-Atrial Intervals and Ventriculo-Atrial Block. | The patient was a 68-year-old female with recurrent paroxysmal, regular narrow QRS complex tachycardia. We observed complete VA conduction block, during tachycardia in our patient. A characteristic feature of our patient is the noticeable irregular atrial and ventricular rates. We considered that possible mechanism of this tachycardia was atrioventricular nodal reentrant tachycardia (AVNRT) with retrograde complete type block in the upper common pathway. |
21,098 | From Incidental, Mechanically-Induced Arrhythmias to Reflex-Defined Arrhythmogenicity: On The Track of The Ternary Reflex System Resemblance to The "Infancy" of New Era or Rediscovery. | The underlying pathophysiology of supraventricular and ventricular arrhythmias remains a matter of intense investigation. Though evolving, the contemporary explanations do not encompass all aspects of arrhythmogenicity. An improved understanding of arrhythmia substrate is needed to augment therapeutic capabilities. Our observation and literature sources demonstrate relatively high incidence of transitory arrhythmias which are non-intentionally generated by the endocardial lead/catheter manipulation. These findings are interesting and potentially may crystallize the reflex-dependent proarrhythmic cardiac activity. Herein we suggest the "reflexogenic arrhythmogenicity" concept extending an overall spectrum of known hypotheses. Cardiovascular reflex action can be categorized into three-tiered levels - intra-cellular, inter-cellular and inter-organic. The first two levels of the triplicate system reside within the cardiac anatomical landmarks (in fact intramurally, intra-organically), however the third one implicates central (cerebral) activity which boomerangs back via centripetal and centrifugal connections. These levels likely compose synoptic ternary reflex set system which may be validated in future studies. To hypothesize, coordinated mutual reciprocity of reflex activity results in stabilization of heart rhythm in robust heart. Any stressful cardiac event may lead to the shift of the rhythm toward unfavorable clinical entity probably via the loss of the influence of dominant reflex. Overall, an interaction and likely intrinsic inter-tiered competition along with possible interplay between physiological and pathological reflexes may be treated as contributing factors for the inception and maintaining of arrhythmias and cardiac performance as well. These assumptions await further documentation. If such a tenet were recognized, the changes in the clinical approach to arrhythmia management might be anticipated, preferably by selective reflex suppression or activation strategy. |
21,099 | ICE Guided CRT: Is there Evidence of Reverse Remodeling? | Cardiac resynchronization therapy (CRT) is an accepted treatment for patients with heart failure (HF), impaired left ventricular (LV) function, and a wide QRS complex. However, more than 30% of eligible patients fail to benefit from CRT. It is clearly necessary to define the characteristics of the best candidates for this therapy. To this end, surface ECG and echocardiography have been tested. Unfortunately, however, neither of these examinations has proved sufficiently able to identify the best patients. A tailored approach based on the evaluation of both electrical and mechanical delay to guide LV lead placement seems to be the most reasonable strategy in order to increase the efficacy of CRT therapy. The good preliminary data that have been published suggest that using intracardiac echocardiography to define the mechanical delay could be an interesting option. Moreover, at present it is the only option available that can enable intraprocedural evaluation of the mechanical activation sequence. Naturally, further randomized studies with larger populations should be performed in order to ascertain the real benefit of this approach and to evaluate whether it will outweigh the additional cost of this technology. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.