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20,400 | Incidence and Time Course for Developing Heart Failure With High-Burden Right Ventricular Pacing. | Although right ventricular pacing can contribute to cardiomyopathy, the impact of complete atrioventricular block (cAVB) on heart failure (HF) development in pacemaker patients has not been well characterized. We evaluated the incidence and time course for developing HF after pacemaker implantation for cAVB.</AbstractText>A MarketScan database identified patients undergoing dual-chamber pacemaker implantation from 2008 to 2014. Patients with cAVB were identified by an atrioventricular node ablation or diagnosis of third-degree AVB. Patients with ≥1 year of continuous MarketScan enrollment before and after implant and without a previous diagnosis of HF were dichotomized into those with cAVB and without AVB. The primary end point was new HF assessed over acute (0-6 months) and chronic (6 months to 4 years) phases post-pacemaker implantation. The cohort included 6994 cAVB patients and 14 208 patients without AVB, followed for 2.35 years (interquartile range, 1.62-3.39 years). After adjustment for baseline covariates, patients with cAVB experienced an increased risk of new-onset HF in the acute phase (hazard ratio, 1.62; 95% confidence interval, 1.48-1.79; P</i><0.001). Although the risk of HF remained elevated among those with cAVB in the chronic phase, the effect was attenuated (hazard ratio, 1.16; 95% confidence interval, 1.08-1.25; P</i><0.001). After pacemaker implantation, younger patients (≤55 years of age) and those with an antecedent history of atrial fibrillation experienced the highest risk of HF associated with cAVB.</AbstractText>Patients with a diagnosis of cAVB, and thus presumed to have a higher burden of right ventricular pacing, experienced an increased risk of new-onset HF after pacemaker implantation compared with those without AVB. Better tools are needed to identify patients at high risk of developing HF in the setting of right ventricular pacing and to determine whether these patients benefit from upfront biventricular pacing.</AbstractText>© 2017 American Heart Association, Inc.</CopyrightInformation> |
20,401 | Left atrial accessory appendages, diverticula, and left-sided septal pouch in multi-slice computed tomography. Association with atrial fibrillation and cerebrovascular accidents. | The aim of this study is to provide a morphometric description of the left-sided septal pouch (LSSP), left atrial accessory appendages, and diverticula using cardiac multi-slice computed tomography (MSCT) and to compare results between patient subgroups.</AbstractText>Two hundred and ninety four patients (42.9% females) with a mean of 69.4±13.1years of age were investigated using MSCT. The presence of the LSSP, left atrial accessory appendages, and diverticula was evaluated. Multiple logistic regression analysis was performed to check whether the presence of additional left atrial structures is associated with increased risk of atrial fibrillation and cerebrovascular accidents.</AbstractText>At least one additional left atrial structure was present in 51.7% of patients. A single LSSP, left atrial diverticulum, and accessory appendage were present in 35.7%, 16.0%, and 4.1% of patients, respectively. After adjusting for other risk factors via multiple logistic regression, patients with LSSP are more likely to have atrial fibrillation (OR=2.00, 95% CI=1.14-3.48, p=0.01). The presence of a LSSP was found to be associated with an increased risk of transient ischemic attack using multiple logistic regression analysis after adjustment for other risk factors (OR=3.88, 95% CI=1.10-13.69, p=0.03).</AbstractText>In conclusion LSSPs, accessory appendages, and diverticula are highly prevalent anatomic structures within the left atrium, which could be easily identified by MSCT. The presence of LSSP is associated with increased risk for atrial fibrillation and transient ischemic attack.</AbstractText>Copyright © 2017 Elsevier B.V. All rights reserved.</CopyrightInformation> |
20,402 | Ivabradine Reduces Digitalis-induced Ventricular Arrhythmias. | The I<sub>(f)</sub> channel inhibitor ivabradine is recommended for treatment of heart failure but also affects potassium currents and thereby prolongs ventricular repolarization. The aim of this study was to examine the electrophysiological effects of ivabradine on digitalis-induced ventricular arrhythmias. Thirteen rabbit hearts were isolated and Langendorff-perfused. After obtaining baseline data, the digitalis glycoside ouabain was infused (0.2 μM). Monophasic action potentials and ECG showed a significant abbreviation of QT interval (-34 ms, p < 0.05) and action potential duration (APD<sub>90</sub> ; -27 ms, p < 0.05). The shortening of ventricular repolarization was accompanied by a reduction in effective refractory period (ERP; -27 ms, p < 0.05). Thereafter, hearts were additionally treated with ivabradine (5 μM). Of note, this did not exert significant effects on QT interval (-4 ms, p = ns) or APD<sub>90</sub> (-15 ms, p = ns) but resulted in an increase in ERP (+17 ms, p < 0.05). This led to a significant increase in post-repolarization refractoriness (PRR, +32 ms, p < 0.01) as compared with sole ouabain treatment. Under baseline conditions, ventricular fibrillation (VF) was inducible by a standardized pacing protocol including programmed stimulation and burst stimulation in four of 13 hearts (31%; 15 episodes). After application of 0.2 μM ouabain, eight of 13 hearts were inducible (62%, 49 episodes). Additional infusion of 5 μM ivabradine led to a significant suppression of VF. Only four episodes could be induced in two of 13 hearts (15%). In this study, ivabradine reduced digitalis-induced ventricular arrhythmias. Ivabradine did not affect ventricular repolarization in the presence of digitalis treatment but demonstrated potent anti-arrhythmic properties based on an increase in both ERP and PRR. The study further characterizes the beneficial electrophysiological profile of ivabradine. |
20,403 | Intermedin improves cardiac function and sympathetic neural remodeling in a rat model of post myocardial infarction heart failure. | Emerging evidence has suggested that intermedin (IMD), a novel member of the calcitonin gene‑related peptide (CGRP) family, has a wide range of cardioprotective effects. The present study investigated the effects of long‑term administration of IMD on cardiac function and sympathetic neural remodeling in heart failure (HF) rats, and studied potential underlying mechanism. HF was induced in rats by myocardial infarction (MI). Male Sprague Dawley rats were randomly assigned to either saline or IMD (0.6 µg/kg/h) treatment groups for 4 weeks post‑MI. Another group of sham‑operated rats served as controls. Cardiac function was assessed by echocardiography, cardiac catheterization and plasma level of B‑type natriuretic peptide (BNP). Cardiac sympathetic neural remodeling was assessed by immunohistochemistical study of tyrosine hydroxylase (TH) and growth associated protein 43 (GAP43) immunoreactive nerve fibers. The protein expression levels of nerve growth factor (NGF), TH and GAP43 in the ventricular myocardium were studied by western blotting. Ventricular fibrillation threshold (VFT) was determined to evaluate the incidence of ventricular arrhythmia. Oxidative stress was assessed by detecting the activity of superoxide dismutase and the level of malondialdehyde. Compared with rats administrated with saline, IMD significantly improved cardiac function, decreased the plasma BNP level, attenuated sympathetic neural remodeling, increased VFT and suppressed oxidative stress. In conclusion, these results indicated that IMD prevents ventricle remodeling and improves the performance of a failing heart. In addition, IMD attenuated sympathetic neural remodeling and reduced the incidence of ventricular arrhythmia, which may contribute to its anti‑oxidative property. These results implicate IMD as a potential therapeutic agent for the treatment of HF. |
20,404 | A Novel Risk Scoring System to Predict Cardiovascular Death in Patients With Acute Myocardial Infarction: CHA<sub>2</sub>DS<sub>2</sub>-VASc-CF Score. | The present study aimed to determine the long-term prognostic validity of the CHA<sub>2</sub>DS<sub>2</sub>-VASc score in patients with acute myocardial infarction (AMI). In addition, we formulated a novel scoring system, the CHA<sub>2</sub>DS<sub>2</sub>-VASc-CF (which includes cigarette smoking and a family history of coronary artery disease as risk factors). This study included 4373 consecutive patients with AMI who presented to the emergency department of our hospital and underwent cardiac catheterization procedures between December 2009 and September 2016. Among these patients, 1427 were diagnosed with ST elevation myocardial infarction (STEMI) and 2946 were diagnosed with non-STEMI. The study included 4373 patients. The study population was divided into 2 groups according to the occurrence of cardiovascular death during the follow-up period. Multivariate logistic regression analysis showed that the CHA<sub>2</sub>DS<sub>2</sub>-VASc-CF score, CHA<sub>2</sub>DS<sub>2</sub>-VASc score, major adverse cardiac events, current cigarette smoking, older age, hypertension, and family history of coronary artery disease were significantly higher, and that the left ventricular ejection fraction and glomerular filtration rate were significantly lower in the cardiovascular death (+) group. Using a cutoff score of >3 for the CHA<sub>2</sub>DS<sub>2</sub>-VASc-CF score, long-term cardiovascular death was predicted with a sensitivity of 78.4% and specificity of 76.4%. The CHA<sub>2</sub>DS<sub>2</sub>-VASc-CF score is suitable for use in all patients with AMI, regardless of the type of treatment, presence of atrial fibrillation, and type of AMI. This risk score, which is easy to calculate, provides important prognostic data. In the future, we think that interventional cardiologists will be able to use this novel scoring system to identify patients with a high risk of long-term cardiovascular death. |
20,405 | Successful treatment of ventricular fibrillation storm triggered by short-long-short sequence; time to avoid managed ventricular pacing. | Sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM) is caused by ventricular tachyarrhythmia that can be effectively treated by implantable cardioverter defibrillator (ICD) therapy. We report of a 28-year-old man with HCM and a dual chamber ICD, originally implanted for primary prevention of SCD, (programmed to AAI(R)-DDD(R); managed ventricular pacing (MVP) mode, Medtronic Inc. St Paul, MN USA). He presented with recurrent ICD shocks due to ventricular fibrillation (VF) despite antiarrhythmic therapy. Careful assessment of the stored electrograms demonstrated a repetitive pattern of VF initiation following short-long-short sequences. Initially, activation of ventricular rate stabilization (VRS) algorithm failed to prevent recurrent VF. Ultimately, deactivation of MVP and reprogramming the device to DDD mode with VRS on, resulted in arrhythmia suppression and avoidance of ICD shocks. Physicians should be aware that although VRS function is available in MVP mode, it does not function in the AAI mode during MVP; in order to effectively treat short-long-short sequence induced ventricular arrhythmia by device programming. |
20,406 | Reliability of updated left ventricular diastolic function recommendations in predicting elevated left ventricular filling pressure and prognosis. | An updated 2016 echocardiographic algorithm for diagnosing left ventricular (LV) diastolic dysfunction (DD) was recently proposed. We aimed to assess the reliability of the 2016 echocardiographic LVDD grading algorithm in predicting elevated LV filling pressure and clinical outcomes compared to the 2009 version.</AbstractText>We retrospectively identified 460 consecutive patients without atrial fibrillation or significant mitral valve disease who underwent transthoracic echocardiography within 24 hours of elective heart catheterization. LV end-diastolic pressure (LVEDP) and the time constant of isovolumic pressure decay (Tau) were determined. The association between DD grading by 2009 LVDD Recommendations and 2016 Recommendations with hemodynamic parameters and all-cause mortality were compared.</AbstractText>The 2009 LVDD Recommendations classified 55 patients (12%) as having normal, 132 (29%) as grade 1, 156 (34%) as grade 2, and 117 (25%) as grade 3 DD. Based on 2016 Recommendations, 177 patients (38%) were normal, 50 (11%) were indeterminate, 124 (27%) patients were grade 1, 75 (16%) were grade 2, 26 (6%) were grade 3 DD, and 8 (2%) were cannot determine. The 2016 Recommendations had superior discriminatory accuracy in predicting LVEDP (P<.001) but were not superior in predicting Tau. During median follow-up of 416 days (interquartile range: 5 to 2004 days), 54 patients (12%) died. Significant DD by 2016 Recommendations was associated with higher risk of mortality (P=.039, subdistribution HR1.85 [95% CI, 1.03-3.33]) in multivariable competing risk regression.</AbstractText>The grading algorithm proposed by the 2016 LV diastolic dysfunction Recommendations detects elevated LVEDP and poor prognosis better than the 2009 Recommendations.</AbstractText>Copyright © 2017 Elsevier Inc. All rights reserved.</CopyrightInformation> |
20,407 | [Establishment of porcine model of prolonged cardiac arrest and cardiopulmonary resuscitation electrically induced by ventricular fibrillation]. | To investigate the optimal injury time point of cardiac arrest (CA) induced electrically, and establish a reproducible prolonged CA and cardiopulmonary resuscitation (CPR) model in pigs.</AbstractText>Forty healthy domestic male pigs were randomly divided into four groups, which were ventricular fibrillation (VF) 8, 10, 11, and 12 minutes groups, each group for 10 animals. In these groups, VF was induced by alternating current delivered to right ventricular endocardium and untreated for 8, 10, 11, and 12 minutes, respectively, followed by 6 minutes of CPR procedure. The resuscitation and survival outcomes were recorded. Hemodynamic parameters and arterial blood gases of animals after successful resuscitation were measured and recorded for 6 hours. Those successful resuscitation animals were regularly evaluated for the neurological deficit score (NDS) and survival outcomes every 24 hours till 96 hours after resuscitation.</AbstractText>The shortest duration of CPR (minute: 6.9±1.3) and the highest successful ratio of the first defibrillation (7/10) were observed in group VF 8 minutes, and the ratio of successful resuscitation was 100%. The best coronary perfusion pressure (CPP) during the CPR, less neurological impairment, longer survival time, more stable hemodynamics, and shorter time for arterial pH and lactate level restoring to the original state after CPR were also observed in group VF 8 minutes, and no severe damage was found in those animals. The longest duration of CPR (minute: 10.3±2.9) and the lowest successful ratio of the first defibrillation (1/10) were observed in group VF 12 minutes, and only 4 animals achieved restoration of spontaneous circulation (ROSC), and no animal survived to CPR 96 hours. The worst CPP during CPR and the highest NDS after resuscitation were also found in VF 12 minutes animals compared to those animals in the other groups. The injuries caused by ischemia and hypoxia in groups VF 10 minutes and VF 11 minutes were in between those of the groups VF 8 minutes and VF 12 minutes, and the duration of CPR were (7.0±2.1) minutes and (8.2±2.6) minutes. There were 9 and 7 animals achieved ROSC in groups VF 10 minutes and VF 11 minutes correspondingly, and 6 and 4 animals survived to 96 hours respectively. Obviously unstable hemodynamics was observed during the period of CPR 2 hours in the two groups. At CPR 1 hour, the heart rates (HR, beats/min) in groups VF 10 minutes and VF 11 minutes increased to 172 (155, 201) and 168 (136, 196) respectively, and the mean arterial pressures (MAP, mmHg, 1 mmHg = 0.133 kPa) declined to 97 (92, 100) and 81 (77, 100), the cardiac output (CO, L/min) decreased to 5.0 (4.0, 5.8), 3.7 (3.0, 5.4) correspondingly. Distinct injuries were found in the two groups [CPR 24-96 hours NDS in groups VF 10 minutes and VF 11 minutes: 180 (110, 255)-20 (0, 400) and 275 (223, 350)-240 (110, 400)], and the arterial pH of the two group decreased to 7.26±0.09 and 7.23±0.09 respectively, and the level of lactate (mmol/L) increased to 9.17±1.48 and 12.80±2.71 correspondingly at CPR 0.5 hour. Significantly lower pH was observed in group VF 11 minutes compared to group VF 8 minutes at CPR 0.5 hour (7.23±0.09 vs. 7.33±0.04, P < 0.05). The highest level of lactate (mmol/L) was also found at the same time point in group VF 11 minutes, which recovered to normal slowly, and was still significantly higher than groups VF 8, 10, 12 minutes (7.58±3.99 vs. 2.55±1.53, 2.13±2.00, 3.40±2.30, all P < 0.05) at CPR 4 hours.</AbstractText>The longer duration of CA was, the more severe damage would be, the longer CPR time would be required, and the harder of the animals to achieve ROSC. In this prolonged CA and CPR porcine model, 10-11 minutes for untreated VF, was an optimal time point with appropriate successful rate of resuscitation, survival outcomes, and post-resuscitation injuries. Therefore, we recommended 10-11 minutes might be the rational length of no-flow time in this model.</AbstractText> |
20,408 | [Experimental study on effect of airway pressure on cardiopulmonary resuscitation]. | To observe the effect of different airway pressure on ventilation, organ perfusion and return of spontaneous circulation (ROSC) of cardiac arrest (CA) pigs during cardiopulmonary resuscitation (CPR), and to explore the possible beneficial mechanism of positive airway pressure during CPR.</AbstractText>Twenty healthy landrace pigs of clean grade were divided into low airway pressure group (LP group, n = 10) and high airway pressure group (HP group, n = 10) with random number table. The model of ventricular fibrillation (VF) was reproduced by electrical stimulation, and mechanical chest compressions and mechanical ventilation (volume-controlled mode, tidal volume 7 mL/kg, frequency 10 times/min) were performed after 8 minutes of untreated VF. Positive end expiratory pressure (PEEP) in LP group and HP group was set to 0 cmH2</sub>O and 6 cmH2</sub>O (1 cmH2</sub>O = 0.098 kPa) respectively. Up to three times of 100 J biphasic defibrillation was delivered after 10 minutes of CPR. The ROSC of animals were observed, and the respiratory parameters, arterial and venous blood gas and hemodynamic parameters were recorded at baseline, 5 minutes and 10 minutes of CPR.</AbstractText>The number of animals with ROSC in the HP group was significantly more than that in the LP group (8 vs. 3, P < 0.05). Intrathoracic pressure during chest compression relaxation was negative in the HP group, and its absolute value was significantly lower than that in LP group at the same time [intrathoracic negative pressure peak (cmH2</sub>O): -4.7±2.2 vs. -10.8±3.5 at 5 minutes, -3.9±2.8 vs. -6.5±3.4 at 10 minutes], however, there was significantly difference only at 5 minutes of CPR (P < 0.01). Intrathoracic pressure variation during CPR period in the HP group were significantly higher than those in the LP group (cmH2</sub>O: 22.5±7.9 vs. 14.2±4.4 at 5 minutes, 23.1±6.4 vs. 12.9±5.1 at 10 minutes, both P < 0.01). Compared to the LP group, arterial partial pressure of oxygen [PaO2</sub> (mmHg, 1 mmHg = 0.133 kPa): 81.5±10.7 vs. 68.0±12.1], venous oxygen saturation (SvO2</sub>: 0.493±0.109 vs. 0.394±0.061) at 5 minutes of CPR, and PaO2</sub> (mmHg: 77.5±13.4 vs. 63.3±10.5), arterial pH (7.28±0.09 vs 7.23±0.11), SvO2</sub> (0.458±0.096 vs. 0.352±0.078), aortic blood pressure [AoP (mmHg): 39.7±9.5 vs. 34.0±6.9], coronary perfusion pressure [CPP (mmHg): 25.2±9.6 vs. 19.0±7.6], and carotid artery flow (mL/min: 44±16 vs. 37±14) at 10 minutes of CPR in the HP group were significantly higher (all P < 0.05). Arterial partial pressure of carbon dioxide (PaCO2</sub>) in the HP group was significantly lower than that in the LP group at 10 minutes of CPR (mmHg: 60.1±9.7 vs. 67.8±8.6, P < 0.05).</AbstractText>Compared to low airway pressure, a certain degree of positive airway pressure can still maintain the negative intrathoracic pressure during relaxation of chest compressions of CPR, while increase the degree of intrathoracic pressure variation. Positive airway pressure can improve oxygenation and hemodynamics during CPR, and is helpful to ROSC.</AbstractText> |
20,409 | Double sequential defibrillation therapy for out-of-hospital cardiac arrests: The London experience. | Despite advances in treatment for out-of-hospital cardiac arrest (OHCA), a subgroup of patients remain in refractory ventricular fibrillation (RVF) during resuscitation. Recent evidence suggests that double sequential defibrillation (DSD), where two shocks are delivered to the patient in quick succession, may provide an effective therapy for RVF. This study describes the characteristics and survival outcomes of OHCA patients treated by ambulance clinicians using a local DSD protocol in an attempt to resolve RVF.</AbstractText>This is a retrospective, observational analysis of patients who received DSD by the London Ambulance Service from 1st July 2015 to 31st December 2016. A comparator group of patients who received more than six consecutive standard shocks (not DSD) for persistent VF was also identified. Outcomes included pre-hospital return of spontaneous circulation (ROSC), ROSC sustained to hospital, and survival to hospital discharge. DSD patients who survived to hospital discharge are reported in further detail.</AbstractText>During the 18-month study period, 45 patients were treated with DSD: a third obtained a pre-hospital ROSC and 7% survived to hospital discharge. We observed similar ROSC and survival rates amongst those who received standard defibrillation only.</AbstractText>Our observational study did not find any clear benefit of DSD use by EMS in the treatment of RVF. However, we find that 3 patients, who were treated with DSD following unsuccessful single shocks, had their VF terminated. Prospective randomised clinical trials are urgently needed to investigate the potential value of DSD in the pre-hospital setting.</AbstractText>Copyright © 2017 Elsevier B.V. All rights reserved.</CopyrightInformation> |
20,410 | A case of pacemaker "malfunction". Should I intervene? | A 53year old lady was noted to have persistent bradycardia in the recovery unit shortly after a dual chamber permanent pacemaker (PPM) was implanted. The patient was asymptomatic. The pacemaker was implanted for symptomatic intermittent complete heart block. She had surgical closure of an atrial septal defect three decades earlier and a previous tricuspid valve replacement with concomitant biatrial cryomaze procedure for paroxysmal atrial fibrillation. |
20,411 | Electrocardiogeriatrics: ECG in advanced age. | The electrocardiogram (ECG) presents substantial changes associated with aging. In fact, the likelihood of having a "normal" ECG decreases with age. The most common findings are left ventricular hypertrophy pattern, leftward axis deviation and QRS widening. Interatrial block (IAB) is frequently present, mainly partial IAB. Atrial fibrillation prevalence raises from 6-7% in those aged 65-74years to 13-17% in those >75years. |
20,412 | Holter-monitored sudden cardiac arrest after atrioventricular junction ablation. | We present a case of sudden cardiac arrest 7 hours after radiofrequency ablation of the atrioventricular junction for symptomatic permanent atrial fibrillation unresponsive to medical therapy. The Holter monitoring revealed a progressive increasing of QT interval after the procedure, highlighting the repolarization instability after acute changes in heart rates associated with modification of ventricular activation, leading to occurrence of short coupling interval ventricular extra beats and finally to a "torsade de pointes." This illustration underlines the need to program a relatively rapid ventricular rate first weeks after junction ablation, especially in case of rapid ventricular rate prior to the procedure, as well as the role of continuous ECG and QT interval monitoring during hospital stay. |
20,413 | Molecular genetic diagnostics for ventricular arrhythmias and sudden cardiac death syndromes. | Inherited forms of ventricular arrhythmias are rare diseases, but a major cause for severe cardiac events, sudden unexplained death syndromes, and death in young adults, infants, and children. Each disorder is genetically heterogeneous (5-20 genes per disease) and molecular testing may include both core genes and less common disease genes as well. Owing to the rapid development and feasibility of sequencing technologies enabling a parallel analysis of several hundred genes up to a whole exome, disease mutations can be identified very efficiently, but have to be seen in the complexity and natural variance of the human genome. Precise phenotypic knowledge and advanced gene variant interpretation are important to ensure adequate patient diagnostics and management. This article focuses on the genetic causes of inherited arrhythmia forms predisposing patients to sudden cardiac death and discusses practical issues and skills for molecular testing. |
20,414 | Lactated Ringer's solution for preventing myocardial reperfusion injury. | Reperfusion of ischemic myocardium is crucial for salvaging myocardial cells from ischemic cell death. However, reperfusion itself induces various deleterious effects on the ischemic myocardium. These effects, known collectively as reperfusion injury, comprise stunned myocardium, reperfusion-induced arrhythmia, microvascular reperfusion injury, and lethal reperfusion injury. No approach has proven successful in preventing any of these injuries in the clinical setting. My colleagues and I recently proposed a new postconditioning protocol, postconditioning with lactate-enriched blood (PCLeB), for the prevention of reperfusion injury. This new approach consists of intermittent reperfusion and timely coronary injections of lactated Ringer's solution, aiming to achieve controlled reperfusion with cellular oxygenation and minimal lactate washout from the cells. This approach appeared to be effective in preventing all types of reperfusion injury in patients with ST-segment elevation myocardial infarction (STEMI), and we have already reported excellent in-hospital outcomes of patients with STEMI treated using PCLeB. In this review article, I discuss a possible mechanism of reperfusion injury, which we believe to be valid and which we targeted using this new approach, and I report how the approach worked in preventing each type of reperfusion injury. |
20,415 | Left atrial appendage function assessment and thrombus identification. | The diagnosis of thrombus in the left atrium in patients with persistent atrial fibrillation (AF) and may be inconsistent because of variability in thrombus morphology. In some cases it is challenging and requires unusual approach. New Doppler-derived methods might be helpful to identify such thrombi. We evaluated quantitative differences in mechanical function of the left atrial appendage (LAA) basal segments using tissue Doppler imaging (TDI)and speckle tracking echocardiography (STE) in patients with non-valvular AF with and without LAA thrombus and compared them with SR patients.</AbstractText>A total of 80 patients with normal left ventricular ejection fraction underwent transesophageal echocardiography (40 patients with SR and 40 patients with AF on oral anticoagulants including patients with LAA thrombus). We analyzed the basal segments of LAA including left lateral ridge (LLR) and baso-medial appendage segment (BMAS). Quantitative analysis was used to calculate peak velocity, average velocity, strain, strain rate and deformation.</AbstractText>In patients with AF the lower LLR strain rate was the sole new STE significant parameter differentiating patients with and without LAA thrombi: - 0.9(- 1.2; - 0.1)s- 1</sup> vs. - 1.6(- 1.9; - 1.3)s- 1</sup>, (p = 0.004). Additionally, patients in SR demonstrated significantly better peak velocity, average velocity, strain, strain rate and deformation than those with AF (p < 0.001).</AbstractText>LLR appeared to be an appropriate site for measuring Doppler derived parameters. It is possible that the strain rate in LLR area may be a novel parameter correlating with the presence of thrombus in patients with AF.</AbstractText> |
20,416 | Comparison of circadian, weekly, and seasonal variations of electrical storms and single events of ventricular fibrillation in patients with Brugada syndrome. | In patients with Brugada syndrome (BS), VF occurred predominantly during the nocturnal period. Some patients also developed ESs. In addition to the circadian rhythm, patients showed weekly and seasonal patterns. The patients with ESs had peak episodes of VF on Saturday and in the winter and spring, while episodes of VF in patients with single VF events occurred most often on Monday with smaller seasonal variation. Except for age, there was no difference in the clinical or ECG characteristics between the patients with ESs and those with single VF episodes. |
20,417 | Left Ventricular Mechanical Reverse Remodelling Not Followed by Electrical Reverse Remodelling: A Case Report. | Patients with severely depressed left ventricular ejection fractions (LVEFs) receive implantable cardioverter-defibrillators (ICDs) for the primary prevention of sudden death. However, in some patients, LVEFs may improve or even normalize over time, and these patients would no longer be qualified for ICD implantation based on the original criteria for which they have initially received an ICD. We report a patient with idiopathic dilated cardiomyopathy whose LVEF recovered to normal values after pharmacological therapy. Meanwhile, the patient had life-threatening ventricular fibrillation, aborted by the ICD. We reflect on the pathological features of left ventricular reverse remodelling and ventricular arrhythmogenesis, where the myocardial substrate appears to play an important role. Also, after LVEF improvement in a patient with a cardiac device, there is still a debate on whether we should perform a battery replacement. |
20,418 | Cardiac resynchronization therapy and its role in the management of heart failure. | The prevalence of heart failure is increasing and it is associated with significant mortality and morbidity. Optimal medical therapy improves outcome, but heart failure continues to have a substantial impact on both the individual patient and wider society. Over the last two decades, cardiac resynchronization therapy has revolutionized the treatment of selected patients who have heart failure. Cardiac resynchronization therapy significantly reduces mortality and hospitalization through reverse cardiac remodelling. This review informs non-specialists about cardiac resynchronization therapy and for which patients it should be considered. |
20,419 | Percutaneous left atrial appendage occlusion procedures in patients with heart failure. | Atrial fibrillation (AF) is the most common supraventricular tachyarrhythmia. Percutaneous left atrial appendage occlusion (LAAO) may be considered for stroke prophylaxis in patients with nonvalvular AF (NVAF), especially in contraindications for oral anticoagulants (OAC) or high risk of bleeding. The data about implantation, safety, efficacy, and follow-up are limited. Moreover, there are no studies on patients with NVAF and heart failure with severe left ventricular systolic dysfunction (left ventricular ejection fraction [LVEF] ≤ 35%).</AbstractText>To assess the safety, efficacy, and mid-term outcomes of LAAO procedures with Amplatzer Cardiac Plug (ACP) and Amplatzer Amulet device in patients with NVAF and heart failure with LVEF ≤ 35% (group I) and to perform a comparative analysis of the patients who had LAAO with NVAF and LVEF > 35%.</AbstractText>The analysis included 80 patients (group I: 19, group II: 61) with NVAF. The patients were enrolled for the study if they had: CHA2DS2VASc ≥ 2 and high risk of bleeding assessed in HAS-BLED (≥ 3) or less points in HAS-BLED but coexisting contraindications for OAC, or thromboembolic complications while using OAC. Time of follow-up was six months.</AbstractText>In the studied population, the median CHA2DS2VASc score was 4 and the average HAS-BLED score was 3.2. Device implantation was successful in all patients from group I and in 59/61 patients from group II. The periprocedural clinical ef-ficacy (no thromboembolic complications) was 100% in group I and 98.4% in group II. Serious periprocedural complications (cardiac tamponade: 2.5%, device embolisation: 1.25%, unexplained death: 1.25%) occurred only in patients from group II (p = NS). The mid-term clinical efficacy was 100% in group I and 98.3% in group II (p = NS). During follow-up, one transient ischaemic attack and three deaths not related to the procedure occurred.</AbstractText>Percutaneous LAAO is an effective and safe procedure in patients with NVAF and severe systolic heart failure. No significant periprocedural and mid-term differences, in terms of safety and efficacy, between the group with severe systolic heart failure (LVEF ≤ 35%) and the group without severe left ventricular systolic dysfunction (LVEF > 35%) were found.</AbstractText> |
20,420 | Right atrial diameter and outcome of catheter ablation of atrial fibrillation. | While AF is considered more like a left atrial (LA) disease, to what extent the right atrium contributes to the pathogenesis and ablation outcome of AF remains unclear. This study aimed to identify if right atrial diameter (RAD) could predict arrhythmia recurrence after catheter ablation of atrial fibrillation (AF).</AbstractText>Four hundred and seventy patients with drug-resistant AF [paroxysmal AF (PAF) 196; non-PAF 274] who underwent primary catheter ablation were enrolled. Ablation strategy included complete bilateral pulmonary vein isolation (PVI) in all patients and additional linear ablation across mitral isthmus, LA roof, and tricuspid isthmus in non-PAF cases. Risk factors associated with recurrence were determined by a Cox regression model, and the predictive power was evaluated by using receiver operating characteristic curve.</AbstractText>After 24.3 ± 18.0 months, 284 patients (60.6%) experienced atrial tachyarrhythmia recurrence (111 in PAF, 173 in non-PAF). RAD was moderately associated with LA diameter (r = 0.371, P < 0.001), left ventricular ejection fraction (r = -0.205, P < 0.001), and left ventricular end-diastolic diameter (r = 0.319, P < 0.001). Multivariate Cox regression analysis demonstrated that RAD was an independent predictor for recurrence only in PAF patients with LAD ≥35 mm (HR 1.044, 95% CI 1.007-1.082, P = 0.021). The RAD cutoff value of 35.5 mm predicts atrial tachyarrhythmia recurrence with 85.4% sensitivity and 29.2% specificity. Kaplan-Meier analysis indicated that RAD over 35.5 mm is associated with more recurrence after PAF ablation (log-rank P = 0.034), comparing to those with RAD <35.5 mm.</AbstractText>RAD predicts outcome of ablation only in patients with PAF and concurrent LA enlargement. Under this condition, RAD <35.5 mm is associated with a more favorable recurrence-free survival at over 2-year follow-up.</AbstractText> |
20,421 | Atrial-ventricular differences in rabbit cardiac voltage-gated Na<sup>+</sup> currents: Basis for atrial-selective block by ranolazine. | Class 1 antiarrhythmic drugs are highly effective in restoring and maintaining sinus rhythm in atrial fibrillation patients but carry a risk of ventricular tachyarrhythmia. The antianginal agent ranolazine is a prototypic atrial-selective voltage-gated Na+</sup> channel blocker but the mechanisms underlying its atrial-selective action remain unclear.</AbstractText>The present study examined the mechanisms underlying the atrial-selective action of ranolazine.</AbstractText>Whole-cell voltage-gated Na+</sup> currents (INa</sub>) were recorded at room temperature (∼22°C) from rabbit isolated left atrial and right ventricular myocytes.</AbstractText>INa</sub> conductance density was ∼1.8-fold greater in atrial than in ventricular cells. Atrial INa</sub> was activated at command potentials ∼7 mV more negative and inactivated at conditioning potentials ∼11 mV more negative than ventricular INa</sub>. The onset of inactivation of INa</sub> was faster in atrial cells than in ventricular myocytes. Ranolazine (30 μM) inhibited INa</sub> in atrial and ventricular myocytes in a use-dependent manner consistent with preferential activated/inactivated state block. Ranolazine caused a significantly greater negative shift in voltage of half-maximal inactivation in atrial cells than in ventricular cells, the recovery from inactivation of INa</sub> was slowed by ranolazine to a greater extent in atrial myocytes than in ventricular cells, and ranolazine produced an instantaneous block that showed marked voltage dependence in atrial cells.</AbstractText>Differences exist between rabbit atrial and ventricular myocytes in the biophysical properties of INa</sub>. The more negative voltage dependence of INa</sub> activation and inactivation, together with trapping of the drug in the inactivated channel, underlies an atrial-selective action of ranolazine.</AbstractText>Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
20,422 | Tracking interlead heterogeneity of R- and T-wave morphology to disclose latent risk for sudden cardiac death. | Sudden cardiac death (SCD) due primarily to ventricular fibrillation claims 1.5 million lives worldwide each year. In 45%-50% of cases, it is the first manifestation of underlying heart disease. Traditional risk factors including smoking, hypertension, age, sex, as well as depressed left ventricular ejection fraction lack sufficient sensitivity and specificity to forewarn of impending life-threatening arrhythmias. There has been a decades-long search for electrocardiographic (ECG) markers of SCD risk. Several interval-based indices such as QT dispersion and T<sub>peak</sub>-T<sub>end</sub> interval held initial promise but ultimately yielded mixed results. Recently, the focus has been on interlead heterogeneity of R- and T-wave morphology. The new approaches have involved advanced analytical tools including vectorcardiographic techniques and second central moment analysis of QRS-aligned templates to quantify heterogeneity of depolarization and repolarization waveforms. The results of current studies appear to be robust and worthy of further exploration. This review examines the electrophysiological underpinnings of heterogeneity-based risk assessment and provides an update of clinical techniques. We also discuss future directions whereby tracking heterogeneity may help to disclose latent risk for SCD not only in ECG recordings made at rest but also during ambulatory ECG monitoring and exercise tolerance testing. |
20,423 | Manifestation of J wave induced by acetylcholine applied for a coronary spasm provocation test in a patient with aborted sudden cardiac death. | A 51-year-old man with a resuscitation episode was referred to our hospital. Coronary angiography revealed a focal spasm overlapped with organic stenosis where a bare metal stent was implanted. Acetylcholine (ACh) provocation test did not induce chest pain. It revealed no discernible ST-T changes but unmasked a J wave at the end of the QRS complex, which was associated with short-coupled repetitive premature ventricular beats. A J wave reportedly appears immediately before the onset of ventricular fibrillation caused by vasospastic angina. However, a J wave observed newly after a coronary spasm provocation test using ACh without ST-T changes is informative when considering the mechanisms of the J wave. |
20,424 | Etiological diagnosis, prognostic significance and role of electrophysiological study in patients with Brugada ECG and syncope. | Syncope is considered a risk factor for life-threatening arrhythmias in Brugada patients. Distinguishing a benign syncope from one due to ventricular arrhythmias is often difficult, unless an ECG is recorded during the episode. Aim of the study was to analyze the characteristics of syncopal episodes in a large population of Brugada patients and evaluate the role of electrophysiological study (EPS) and the prognosis in the different subgroups.</AbstractText>One hundred ninety-five Brugada patients with history of syncope were considered. Syncope were classified as neurally mediated (group 1, 61%) or unexplained (group 2, 39%) on the basis of personal and family history, clinical features, triggers, situations, associated signs, concomitant therapy. Most patients underwent EPS; they received ICD or implantable loop-recorder on the basis of the result of investigations and physician's judgment. At 62±45months of mean follow-up, group 1 showed a significantly lower incidence of arrhythmic events (2%) as compared to group 2 (9%, p<0.001). Group 2 patients with positive EPS showed the highest risk of arrhythmic events (27%). No ventricular events occurred in subjects with negative EPS.</AbstractText>Etiological definition of syncope in Brugada patients is important, as it allows identifying two groups with different outcome. Patients with unexplained syncope and ventricular fibrillation induced at EPS have the highest risk of arrhythmic events. Patients presenting with neurally mediated syncope showed a prognosis similar to that of the asymptomatic and the role of EPS in this group is unproven.</AbstractText>Copyright © 2017 Elsevier B.V. All rights reserved.</CopyrightInformation> |
20,425 | Prescribing an automated external defibrillator for children at increased risk of sudden arrhythmic death. | Automated external defibrillators can be life-saving in out-of-hospital cardiac arrest.</AbstractText>Our aim was to review our experience of prescribing automated external defibrillators for children at increased risk of sudden arrhythmic death.</AbstractText>We reviewed all automated external defibrillators issued by the Scottish Paediatric Cardiac Electrophysiology Service from 2005 to 2015. All parents were given resuscitation training according to the Paediatric Resuscitation Guidelines, including the use of the automated external defibrillator.</AbstractText>A total of 36 automated external defibrillators were issued to 36 families for 44 children (27 male). The mean age at issue was 8.8 years. Diagnoses at issue included long QT syndrome (50%), broad complex tachycardia (14%), hypertrophic cardiomyopathy (11%), and catecholaminergic polymorphic ventricular tachycardia (9%). During the study period, the automated external defibrillator was used in four (9%) children, and in all four the automated external defibrillator correctly discriminated between a shockable rhythm - polymorphic ventricular tachycardia/ventricular fibrillation in three patients with one or more shocks delivered - and non-shockable rhythm - sinus rhythm in one patient. Of the three children, two of them who received one or more shocks for ventricular fibrillation/polymorphic ventricular tachycardia survived, but one died as a result of recurrent torsades de pointes. There were no other deaths.</AbstractText>Parents can be taught to recognise cardiac arrest, apply resuscitation skills, and use an automated external defibrillator. Prescribing an automated external defibrillator should be considered for children at increased risk of sudden arrhythmic death, especially where the risk/benefit ratio of an implantable defibrillator is unclear or delay to defibrillator implantation is deemed necessary.</AbstractText> |
20,426 | Pitfalls in TAMVI: experience with the repositionable Lotus® Valve System. | Simultaneous transapical implantation of transcatheter heart valves in the native mitral and aortic position may be considered as an alternative to surgical valve replacement in high-risk patients presenting with combined valve disease.</AbstractText>A 59-year-old female with severe aortic stenosis, severe mitral stenosis with mild mitral insufficiency, persistent atrial fibrillation, severe chronic obstructive pulmonary disease and NYHA class of IV was evaluated by our interdisciplinary heart team. Due to the calculated Euroscore II, logistic Euroscore with 10% and 17% a decision was made towards a transapical TAVI approach. The implantation of a Sapien 3 (Edwards Lifesciences) valve in the aortic position was performed and the perioperative TEE showed a good result. The preoperative imaging revealed a narrow LVOT with risk for post interventional left ventricular outflow tract obstruction. Accordingly, it was decided against the use of balloon-expanding valves for the mitral valve position in the interdisciplinary team, as it is not repositionable. Instead, it was decided for the use of a Lotus (Boston Scientific) valve, as it is repositionable and therefore possible to retract in case of LVOT obstruction. In the present case of double valve intervention, the implantation attempt of a fully repositionable transcatheter heart valve into the native mitral annulus resulted in acute LVOT obstruction requiring immediate removal of the device. The patient was extubated and experienced uneventful postoperative recovery.</AbstractText>The case shows that improved preoperative work-up is necessary for better prediction of significant LVOT obstruction following transcatheter mitral valve implantation. In borderline cases, the use of a fully repositionable device is preferred.</AbstractText> |
20,427 | Surgical ablation for persistent atrial fibrillation in concomitant cardiac surgery: mid-long-term result. | Surgical ablation is an option for patients with atrial fibrillation (AF) undergoing concomitant cardiac surgery. This study aims to evaluate the outcome of surgical ablation during concomitant cardiac surgery and to identify the independent predictors for a primary end-point consisting of AF or atrial flutter (AFL) recurrence, death, permanent pacemaker implantation and necessity for anti-arrhythmic drugs and the effects of reintervention for AF/AFL recurrence.</AbstractText>A retrospective analysis was performed for 1028 patients who underwent surgical ablation during concomitant cardiac surgery from October 2004 to April 2015. Nine hundred and twenty-seven of 1017 (91.2%) discharged patients were followed up. Sixty-three recurrent patients received reintervention. Predictors of ablation failure were identified using univariate analysis and the Cox regression model.</AbstractText>The mean follow-up length was 29.0 ± 22.7 months. The New York Heart Association class, ejection fraction, left atrial and right atrial diameters and left ventricular end-diastolic diameter were improved at follow-up compared with the preoperative status. The rate of freedom from the primary end-point at 1, 2 and 3 years was 86.8, 79.4 and 68.3%. Independent predictors of reaching the primary end-point were AF/AFL at discharge, preoperative right atrial diameter, hypertension, diabetes and smoking. The rate of sinus rhythm without anti-arrhythmic drugs at 12, 24 and 36 months after reintervention was 78.3, 62.8 and 49.9%, respectively.</AbstractText>Surgical ablation has a high success rate and may improve cardiac function postoperatively. AF/AFL at discharge, preoperative right atrial diameter, hypertension, diabetes and smoking are the major independent predictors for ablation failure. Reintervention in AF/AFL recurrent patients can achieve a favourable clinical outcome.</AbstractText>© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.</CopyrightInformation> |
20,428 | Population-based values and abnormalities of the electrocardiogram in the general Dutch population: The LifeLines Cohort Study. | Our aim is to present average values and prevalence of electrocardiographic (ECG) abnormalities among the general Dutch population in the LifeLines Cohort.</AbstractText>The ECG values previously studied in the Caucasian population of smaller cohorts will be confirmed with ECG data from LifeLines.</AbstractText>ECG data of 152 180 individuals age 18 to 93 years were available. Individuals with cardiovascular risk factors were excluded to analyze the healthy population. Average values of the ECG for the healthy population were presented as means with 95% and 99% confidence intervals and as medians with first and 99th percentiles.</AbstractText>Median heart rate was highest in the youngest and oldest individuals of the healthy population. Median duration of P wave, PQ interval, and QRS duration were longer in males compared with females. In contrast, median QT interval corrected for heart rate was higher in females. In general, the above-mentioned parameters increased with age. The prevalences of ECG abnormalities adjusted for the Dutch population were 0.9% for atrial fibrillation or flutter, 1.4% for premature atrial complexes, 0.5% for myocardial infarction, 2.1% for ventricular premature complexes, 1.0% for left ventricular hypertrophy, 8.1% for P-R interval >200 ms, and 0.8% for bundle branch block.</AbstractText>Our study provides an overview of average values and ECG abnormalities and confirms data of previous smaller studies. In addition, we evaluate the age- and sex-dependent normal limits of the P wave and QRS duration and confirm in detail the frontal plane QRS-T angle on the ECG.</AbstractText>© 2017 Wiley Periodicals, Inc.</CopyrightInformation> |
20,429 | Antitachycardia pacing programming in implantable cardioverter defibrillator: A systematic review. | Implantable cardioverter defibrillator (ICD) programming involves several parameters. In recent years antitachycardia pacing (ATP) has gained an increasing importance in the treatment of ventricular arrhythmias, whether slow or fast. It reduces the number of unnecessary and inappropriate shocks and improves both patient's quality of life and device longevity. There is no clear indication regarding the type of ATP to be used, except for the treatment of fast ventricular tachycardias (188 bpm-250 bpm) where it has been shown a greater efficacy and safety of burst compared to ramp; 8 impulses in each sequence of ATP appears to be the best programming option in this setting. Beyond ATP use, excellent clinical results were obtained with programming standardization following these principles: extended detection time in ventricular fibrillation (VF) zone; supraventricular discrimination criteria up to 200 bpm; first shock in VF zone at the maximum energy in order to reduce the risk of multiple shocks. The MADIT-RIT trial and some observational registries have also recently demonstrated that programming with a widespread use of ATP, higher cut-off rates or delayed intervention reduces the number of inappropriate and unnecessary therapies and improves the survival of patients during mid-term follow-up. |
20,430 | Etiological diagnoses of out-of-hospital cardiac arrest survivors admitted to the intensive care unit: Insights from a French registry. | Respective proportions of final etiologies are disparate in cohorts of cardiac arrest patients, depending on examined population and diagnostic algorithms. In particular, prevalence and characteristics of sudden unexplained death syndrome (SUDS) are debated. We aimed at describing etiologies in a large cohort of aborted out-of-hospital cardiac arrest (OHCA) patients, in order to assess prevalence and outcome of SUDS.</AbstractText>We analyzed data from our prospective registry of successfully resuscitated OHCA patients admitted to a cardiac arrest centre between January 2002 and December 2014. The in-ICU diagnostic strategy included early coronary angiogram, brain and chest CT scan. This was completed by an extensive diagnostic strategy, encompassing biological and toxicological tests, repeated electrocardiograms and echocardiography, MRI and pharmacologic tests. Two independent investigators reviewed each final diagnosis. Baseline characteristics were compared between subgroups of patients. Three-month mortality was compared between subgroups using univariate Kaplan-Meier curves.</AbstractText>Over the study period, 1657 patients were admitted to our unit after an aborted OHCA. The event was attributed to a non-cardiac and a cardiac cause in 478 (32.0%) and 978 (65.5%) patients, respectively. The main cause of cardiac related OHCA was ischemic heart disease (76.7%) while primary electrical diseases accounted for only 2.5%. Sudden unexplained deaths (SUDS) were observed in 37 (2.5%) patients.</AbstractText>We observed that ischemic heart disease was by far the most common cause of cardiac arrest, while primary electrical diseases were much less frequent. SUDS accounted for a very small proportion of patients who suffered an aborted OHCA.</AbstractText>Copyright © 2017 Elsevier B.V. All rights reserved.</CopyrightInformation> |
20,431 | Atrial Fibrillation in Hypertrophic Cardiomyopathy. | Hypertrophic cardiomyopathy (HCM) is an inherited cardiac disorder with a spectrum of clinical manifestations. Patients with HCM are predisposed to developing atrial fibrillation (AF) due primarily to advanced diastolic dysfunction and left atrial (LA) dilatation and remodelling. Atrial fibrillation causes a progressive symptomatic and functional decline, as well as increased thromboembolic risk and mortality, particularly in the setting of rapid ventricular rates and left ventricular outflow tract (LVOT) obstruction. The mainstay of management of AF in HCM is a combination of non-pharmacological lifestyle and risk factor modification, long-term anticoagulation, and rhythm control with antiarrhythmic medications. There is a growing body of evidence indicating that an early and aggressive rhythm control strategy may result in more favourable outcomes. |
20,432 | Treatment of Ventricular Arrhythmias and Use of Implantable Cardioverter-Defibrillators to Improve Survival in Older Adult Patients with Cardiac Disease. | Ventricular arrhythmia (VA) and sudden cardiac death (SCD) are well-recognized problems in the overall heart failure population, but treatment decisions can be more complex and nuanced in older patients. Sustained VA does not always lead to SCD, but identifies a higher risk population and may cause significant symptoms. Antiarrhythmic drugs (AAD) and catheter ablation are the mainstays for prevention of VA, but have not been shown to improve mortality. The value of implantable cardiac defibrillators (ICDs) may be influenced by patient age. This article discusses long-term treatment of VA and the use of ICDs in the elderly. |
20,433 | Atrial Fibrillation in Anaphylaxis. | The relationship between anaphylaxis and cardiovascular events has been reported in the past. While skin and respiratory symptoms are usually the most common and the first to appear, cardiovascular complications play a key role and represent the leading cause of death in anaphylaxis.</AbstractText>We report 3 episodes of atrial fibrillation triggered by anaphylaxis. Allergy and cardiology studies were performed. In both patients, the etiological agent was identified: Anisakis simplex hypersensitivity and food allergy.</AbstractText>The heart is the source and target of chemical mediators released during an allergic reaction. In the heart, there are plenty of mast cells, and they are predominantly located around the coronary adventitia and in close contact with small vessels in the muscle wall. The release of mediators can influence ventricular function, heart rate, and coronary artery tone. Anaphylaxis can trigger any kind of arrhythmia. In these cases, the very interesting point of discussion was: which should be first, treating anaphylaxis or cardiac events? The other controversial point was the use of epinephrine, the first line of treatment for anaphylaxis. Recommendations about epinephrine in cardiac patients during an anaphylactic event are still a major dilemma.</AbstractText>We emphasize the importance of the priority of establishing protocols between cardiologist and allergist in treatment of cardiac complications during anaphylaxis, and we warn about the correct diagnosis of arrhythmias in anaphylaxis in order to treat them as soon as possible, to prevent other consequences and complications.</AbstractText>Copyright © 2017 Elsevier Inc. All rights reserved.</CopyrightInformation> |
20,434 | Right ventricular dysfunction in left-sided heart failure with preserved versus reduced ejection fraction. | Right ventricular (RV) dysfunction is recognized as a major prognostic factor in left-sided heart failure (HF). However, the relative contribution of RV dysfunction in HF with preserved (HFpEF) vs. reduced ejection fraction (HFrEF) is unclear.</AbstractText>Right ventricular longitudinal strain (RVLS), tricuspid annular plane systolic excursion (TAPSE) and pulmonary artery systolic pressure (PASP) were determined by echocardiography in 657 age- and gender-matched groups of patients with HFpEF [left ventricular ejection fraction (LVEF) ≥50%; n=219] and HFrEF (LVEF <50%; n=219) and in controls without HF (n=219) from an Asian population-based cohort study. Across control to HFpEF and HFrEF groups, RV function deteriorated as measured by RVLS (-26.7 ± 5%, -22.7±6.6% and -18.2 ± 6.7%, respectively) and TAPSE (21.0 ± 3.9, 17.5 ± 5.1 and 14.7 ± 4.7 mm, respectively), whereas PASP increased (26.8 ± 7.1, 34.5 ± 11.9 and 39.3 ± 16.2 mmHg, respectively) (all P<0.001). Controlling for PASP in control, HFpEF and HFrEF subjects, the magnitude of RVLS/PASP (-1.06 ± 0.32, -0.75 ± 0.32 and -0.56 ± 0.36, respectively) and TAPSE/PASP ratios (0.83 ± 0.23, 0.54 ± 0.24 and 0.55 ± 0.29, respectively) similarly decreased across groups. Right ventricular dysfunction (by both TAPSE and RVLS) was independently associated with left ventricular systolic dysfunction and atrial fibrillation, but not with PASP. Among patients with HF, both TAPSE/PASP and RVLS/PASP ratios were related to the composite endpoint of all-cause death and HF hospitalization, even after multivariable adjustment [hazard ratio (HR) 0.33; 95% confidence interval (CI) 0.14-0.74 and HR 3.09; 95% CI 1.52-6.26, respectively], with no difference between HFrEF and HFpEF.</AbstractText>Right ventricular dysfunction is present in HFpEF and is even more pronounced in HFrEF for any given degree of pulmonary hypertension. It is independently predicted by left ventricular dysfunction but not by PASP. Right ventricular-arterial coupling is prognostically important in HF regardless of LVEF.</AbstractText>© 2017 The Authors. European Journal of Heart Failure © 2017 European Society of Cardiology.</CopyrightInformation> |
20,435 | Effects of Levosimendan on Patients with Heart Failure Complicating Acute Coronary Syndrome: A Meta-Analysis of Randomized Controlled Trials. | The prognosis for patients with heart failure (HF), including cardiogenic shock (CS), complicating acute coronary syndrome (ACS) remains poor.</AbstractText>This study aimed to review the relevant literature and evaluate whether levosimendan was associated with better clinical outcomes in these patients.</AbstractText>We searched PubMed, EMBASE, and the Cochrane library databases for randomized controlled trials that investigated levosimendan compared with any control in patients with HF/CS complicating ACS.</AbstractText>A total of 1065 patients from nine trials were included in this study. Analysis showed that levosimendan significantly reduced total mortality and the incidence of worsening HF. In patients with HF-ACS, levosimendan was associated with reduced mortality. In patients with CS-ACS, no significant difference was observed between the two groups. Levosimendan contributed to significantly reduced mortality when compared with placebo, but no significant reduction was seen compared with dobutamine. Compared with controls, levosimendan decreased pulmonary capillary wedge pressure and systemic vascular resistance and increased cardiac index, with no significant difference observed between the groups in terms of heart rate. Levosimendan non-significantly increased the risk of hypotension but did not increase the risk of ischemic episodes, sinus tachycardia, atrial fibrillation, or ventricular arrhythmias.</AbstractText>Levosimendan appears to be a promising drug to reduce mortality and worsening HF in patients with HF/CS-ACS. It appears to provide hemodynamic benefit and was associated with an increased risk of hypotension.</AbstractText> |
20,436 | Differential regulation of protein phosphatase 1 (PP1) isoforms in human heart failure and atrial fibrillation. | Protein phosphatase 1 (PP1) is a key regulator of important cardiac signaling pathways. Dysregulation of PP1 has been heavily implicated in cardiac dysfunctions. Accordingly, pharmacological targeting of PP1 activity is considered for therapeutic intervention in human cardiomyopathies. Recent evidence from animal models implicated previously unrecognized, isoform-specific activities of PP1 in the healthy and diseased heart. Therefore, this study examined the expression of the distinct PP1 isoforms PP1α, β, and γ in human heart failure (HF) and atrial fibrillation (AF) and addressed the consequences of β-adrenoceptor blocker (beta-blocker) therapy for HF patients with reduced ejection fraction on PP1 isoform expression. Using western blot analysis, we found greater abundance of PP1 isoforms α and γ but unaltered PP1β levels in left ventricular myocardial tissues from HF patients as compared to non-failing controls. However, expression of all three PP1 isoforms was higher in atrial appendages from patients with AF compared to patients with sinus rhythm. Moreover, we found that in human failing ventricles, beta-blocker therapy was associated with lower PP1α abundance and activity, as indicated by higher phosphorylation of the PP1α-specific substrate eIF2α. Greater eIF2α phosphorylation is a known repressor of protein translation, and accordingly, we found lower levels of the endoplasmic reticulum (ER) stress marker Grp78 in the very same samples. We propose that isoform-specific targeting of PP1α activity may be a novel and innovative therapeutic strategy for the treatment of human cardiac diseases by reducing ER stress conditions. |
20,437 | [Diagnosis of ischemia and revascularization in patients with ventricular tachyarrhythmia]. | Sustained ventricular tachyarrhythmia usually occurs on the basis of structural heart disease, particularly coronary heart disease (CAD). Although monomorphic ventricular tachycardia (VT) appears mainly in patients with CAD, it is typically not triggered by acute ischemia, in contrast to polymorphic VT or ventricular fibrillation (VF). To judge if VT is caused by acute ischemia is even more difficult in context with an elevated highly sensitive troponin T which is generally elevated in sustained VT because tachycardia in chronic stable coronary artery sclerosis causes a mismatch between increased oxygen demand and limited oxygen supply. Therefore, acute coronary angiography and revascularization may frequently not be necessary in monomorphic VT, will usually not improve rhythm stabilization, and may lead to misinterpretation of monomorphic VT being caused by a coronary stenosis. This can lead to withholding antiarrhythmic therapy after revascularization since it is assumed that the cause of VT has been treated. On the other hand, acute coronary angiography and revascularization are useful in polymorphic VT/VF, ECG signs of ischemia, or typical chest pain before occurrence of VT/VF. Coronary angiography should also be performed in patients with VT with newly diagnosed reduced left ventricular function and before catheter ablation. |
20,438 | Calcium Signaling and Cardiac Arrhythmias. | There has been a significant progress in our understanding of the molecular mechanisms by which calcium (Ca<sup>2+</sup>) ions mediate various types of cardiac arrhythmias. A growing list of inherited gene defects can cause potentially lethal cardiac arrhythmia syndromes, including catecholaminergic polymorphic ventricular tachycardia, congenital long QT syndrome, and hypertrophic cardiomyopathy. In addition, acquired deficits of multiple Ca<sup>2+</sup>-handling proteins can contribute to the pathogenesis of arrhythmias in patients with various types of heart disease. In this review article, we will first review the key role of Ca<sup>2+</sup> in normal cardiac function-in particular, excitation-contraction coupling and normal electric rhythms. The functional involvement of Ca<sup>2+</sup> in distinct arrhythmia mechanisms will be discussed, followed by various inherited arrhythmia syndromes caused by mutations in Ca<sup>2+</sup>-handling proteins. Finally, we will discuss how changes in the expression of regulation of Ca<sup>2+</sup> channels and transporters can cause acquired arrhythmias, and how these mechanisms might be targeted for therapeutic purposes. |
20,439 | Subclinical Myocardial Impairment in Metabolic Diseases. | Type 2 diabetes mellitus (T2DM) and obesity are important contributors to nonischemic heart failure (HF) and atrial fibrillation. There is a 2- to 5-fold increase in HF associated with T2DM, and there is a 5% in HF risk in men and 7% increment in women for every unit increment in body mass index, after adjustment for traditional cardiovascular risk factors. Likewise, the risk of atrial fibrillation increases by about 6% per unit increase in body mass index. Metabolic cardiomyopathy leads to a number of changes in cardiac structure and function that can be recognized by imaging in the asymptomatic phase, and these parameters can be used for monitoring the progression of disease or the response to therapy. The purpose of this review is to familiarize clinicians with the potential benefits of early detection of preclinical myocardial abnormalities, as well as the mechanisms that might inform interventions to prevent disease progression in patients with T2DM and obesity. |
20,440 | Neuroprotective Effects of Drug-Induced Therapeutic Hypothermia in Central Nervous System Diseases. | This review article focuses on the neuroprotective effect of drug-induced hypothermia in cerebrovascular diseases and discusses its related side effects.</AbstractText>A systematic literature search was performed using Pubmed and Embase electronic databases for a retrospective analysis.</AbstractText>Experimental studies have shown that drug-induced hypothermia alleviates brain damage and plays a neuroprotective role, thereby reducing mortality and ameliorating neurological deficits. Therefore, drug-induced hypothermia has an important research value and is worth further consideration in the clinical setting. However, drug-induced hypothermia is also associated with side effects, such as ventricular tachycardia, ventricular fibrillation, suppressed immune function, infection, electrolyte imbalance, glucose metabolism disorders, and skeletal muscle tremor. Existing drugs with cooling effects belong to the following categories: (1) dopamine receptor agonists; (2) cannabis; (3) opioid receptors; (4) vanilloid receptors; (5) vasopressins (potent neurotensin receptor agonists); (6) thyroid drugs; (7) adenosine drugs; and (8) purine drugs.</AbstractText>Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.</CopyrightInformation> |
20,441 | Supraventricular arrhythmias in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy associate with long-term outcome after catheter ablation of ventricular tachycardias. | This study aimed to assess the impact of supraventricular tachycardia (SVT) on long-term results of radiofrequency catheter ablation therapy of ventricular tachycardia (VT) in a large cohort of patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C).</AbstractText>Supraventricular tachycardia occurrence has been studied in patients from our ARVD/C registry (70 patients, 48 male, age 53.2 ± 14.0, 45 patients (64.3%) with previous VT ablation). SVT were diagnosed in 26 of 70 patients (37.1%). Atrial fibrillation (AF) was the most frequent atrial arrhythmia, diagnosed in 17 patients (24.3%). In univariate analysis advanced age, clinical symptoms of heart failure, enlarged right atrium, diagnosis of significant tricuspid regurgitation (TR), and inappropriate implantable cardioverters-defibrillators therapy were associated with SVT. In binary logistic regression analysis only heart failure: hazard ratio (HR) 10.89, 95% confidence interval (95% CI) 1.08-109.96 (P = 0.043) and significant TR: HR 4.79, 95% CI 1.35-16.33 (P = 0.015) remained associated with SVT. In patients with previous VT ablation Cox multiple regression survival analysis revealed older age (≥53 years): HR 4.63, 95% CI 1.51-14.24 (P = 0.008) and SVT: HR 3.01, 95% CI 1.15-7.89 (P = 0.025) as predictors for VT recurrence during the follow-up.</AbstractText>SVT and older age are associated with the recurrence of VT after catheter ablation in patients with ARVD/C.</AbstractText> |
20,442 | Cardiac resynchronization therapy and electrical storm: results of the OBSERVational registry on long-term outcome of ICD patients (OBSERVO-ICD). | Electrical storm (ES) is a condition defined as three or more episodes of ventricular fibrillation (VF) or ventricular tachycardia (VT) within 24 h, and usually coexist with advanced heart failure in patients with structural heart disease. The aim of the present study is to test whether cardiac resynchronization therapy (CRT) can be associated with a lower incidence of ES.</AbstractText>The OBSERVO-ICD (NCT02735811) is a multicentre, retrospective registry, enrolling all consecutive patients undergoing ICD or CRT-D implantation from 2010 to 2012 in five Italian high-volume arrhythmia centres. Propensity score matching was used to compare two equally sized cohorts of ICD and CRT-D patients with similar characteristics. The primary endpoint was the time free from ES. Secondary endpoints were time free from unclustered VT/VF episodes and time free from ES in CRT-D patients according to clinical or echographic response. CRT-D was associated with a 45% relative risk reduction in ES when compared with ICD (5.6% vs. 12.3%; log rank P = 0.014). CRT-responders presented lower rates of ES when compared with non-responders and negative responders according to both clinical and echographic criteria (log-rank P = 0.017 and 0.023, respectively). No ES was detected in any of the 133 full responders to CRT-D. Clinical and echographic positive responses, but not CRT-implant per se, were associated with lower estimate rates of unclustered VTs/VFs.</AbstractText>Patients with CRT had a lower incidence of ES when compared with propensity-matched ICD patients. The long-term benefit of CRT seems to be due to the improved haemodynamics, as CRT-responders performed markedly better over a long-term follow-up.</AbstractText> |
20,443 | Factors associated with delayed defibrillation in cardiopulmonary resuscitation: A prospective simulation study. | Early defibrillation is an important factor of survival in cardiac arrest. However, novice resuscitators often struggle with cardiac arrest patients. We investigated factors leading to delayed defibrillation performed by final-year medical students within a simulated bystander cardiac arrest situation.</AbstractText>Final-year medical students received a refresher lecture and basic life support training before being confronted with a simulated cardiac arrest situation in a simulation ambulance. The scenario was analyzed for factors leading to delayed defibrillation. We compared the time intervals the participants needed for various measures with a benchmark set by experienced resuscitators. After training, the participants were interviewed regarding challenges and thoughts during the scenario.</AbstractText>The median time needed for defibrillation was 158 s (n = 49, interquartile range: 107-270 s), more than six-fold of the benchmark time. The major part of total defibrillation time (49%; median, n = 49) was between onset of ventricular fibrillation and beginning to prepare the defibrillator, more specifically the time between end of preparation of the defibrillator and actual delivery of the shock, with a mean proportion of 26% (n = 49, SD = 17%) of the overall time needed for defibrillation (maximum 67%). Self-reported reasons for this delay included uncertainty about the next step to take, as reported by 73% of the participants. A total of 35% were unsure about which algorithm to follow. Diagnosing the patient was subjectively difficult for 35% of the participants. Overall, 53% of the participants felt generally confused.</AbstractText>Our study shows that novice resuscitators rarely achieve guideline-recommended defibrillation times. The most relative delays were observed when participants had to choose what to do next or which algorithm to follow, and thus i.e. performed extensive airway management before a life-saving defibrillation. Our data provides a first insight in the process of defibrillation delay and can be used to generate new hypotheses on how to provide a timely defibrillation.</AbstractText> |
20,444 | Seasonal variation in patient characteristics and in-hospital outcomes of Takotsubo syndrome: a nationwide retrospective cohort study in Japan. | Although there is reportedly seasonal variation in the occurrence of Takotsubo syndrome (TTS), it is unknown whether there is a relationship between season and patient characteristics, or whether season influences outcomes. Using the Diagnosis Procedure Combination database in Japan, we retrospectively identified 4306 patients (mean age 73.6 years) hospitalized with TTS between January 2011 and December 2013. We divided patients into four groups according to season of admission [n = 914, Spring (March-May); n = 1243, Summer (June-August); n = 1245, Autumn (September-November); n = 904, Winter (December-February)]. The outcomes were in-hospital mortality and cardiovascular complications. We compared patient backgrounds and outcomes across seasons and estimated the adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for outcomes in logistic regression analyses adjusted for multiple propensity scores. Although there was no significant difference in age across seasons, the proportion of males differed significantly (from 18.5% in autumn to 23.9% in winter; p = 0.016). The incidence of psychiatric disease (from 4.9% in spring to 7.9% in summer; p = 0.025) and sepsis (from 0.8% in winter to 2.6% in summer; p = 0.019) also differed significantly with season. In-hospital mortality was not significantly influenced by season (p = 0.377): spring, 5.1%; summer, 6.0%; autumn, 4.6%; winter, 6.0%. However, in-hospital mortality ranged widely across months from 3.0% in September to 7.5% in April. The incidence of ventricular tachycardia/fibrillation was significantly different (p = 0.038): spring, 2.2% (reference); summer, 3.3% (aOR 1.46, 95% CI 0.84-2.51); autumn, 2.7% (aOR 1.27, 95% CI 0.72-2.22); winter, 4.4% (aOR 1.92, 95% CI 1.11-3.33). Although season did not appear to influence the in-hospital mortality of TTS, monthly variation may exist in the risk of death in patients with TTS. There were significant seasonal variations in the proportions of males, patients with psychiatric disease or sepsis, and the incidence of ventricular arrhythmias among patients with TTS. |
20,445 | How to detect atrial fibrosis. | In the last twenty years, new imaging techniques to assess atrial function and to predict the risk of recurrence of atrial fibrillation after treatment have been developed. The present review deals with the role of these techniques in the detection of structural and functional changes of the atrium and diagnosis of atrial remodeling, particularly atrial fibrosis. Echocardiography allows the detection of anatomical, functional changes and deformation of the atrial wall during the phases of the cardiac cycle. For this, adequate acquisition of atrial images is necessary using speckle tracking imaging and interpretation of the resulting strain and strain rate curves. This allows to predict new-onset atrial fibrillation and recurrences. Its main limitations are inter-observer variability, the existence of different software manufacturers, and the fact that the software used were originally developed for the evaluation of the ventricular function and are now applied to the atria. Cardiac magnetic resonance, using contrast enhancement with gadolinium, plays a key role in the visualization and quantification of atrial fibrosis. This is the established method for <i>in vivo</i> visualization of myocardial fibrotic tissue. The non-invasive evaluation of atrial fibrosis is associated with the risk of recurrence of atrial fibrillation and with electro-anatomical endocardial mapping. We discuss the limitations of these techniques, derived from the difficulty of demonstrating the correlation between fibrosis imaging and histology, and poor intra- and inter-observer reproducibility. The sources of discordance are described, mainly due to image acquisition and processing, and the challenges ahead in an attempt to eliminate differences between operators. |
20,446 | Atrial Fibrillation in Patients Hospitalized With Heart Failure: Patient Characteristics and Outcomes From the HEARTS Registry. | Effect of atrial fibrillation (AF) on short- and long-term outcomes in heart failure (HF) is controversial. Accordingly, we examined this relationship in a national multicenter project using data from the Hearts Function Assessment Registry Trial in Saudi Arabia that studied the clinical features and outcomes of patients admitted with de novo and acute on chronic HF. Out of 2593 patients with HF, 449 (17.8%) had AF at presentation. Patients with AF were more likely to be males and older (mean age 65.2 ± 15.0 vs 60.5 ± 14.8 years) to have a history of ventricular tachycardia/ventricular fibrillation (3.1% vs 1.9%) or cerebrovascular accident (15.0% vs 8.5%). However, they were less likely to have diabetes (66.0% vs 55.9%) or coronary artery disease (55.6% vs 42.3%). The 1-, 2-, and 3-year crude mortality rates were significantly higher in patients with AF (23.2% vs 18.3%, 27.4% vs 22.3%, and 27.8% vs 23.2%, respectively). However, there was no significant difference in mortality after adjusting for covariates. Thus, in patients admitted with HF, AF upon presentation was not associated with increased mortality. |
20,447 | Changes in arrhythmogenic properties and five-year prognosis after carbon-ion radiotherapy in patients with mediastinum cancer. | Carbon-ion irradiation of rabbit hearts has improved left ventricular conduction abnormalities through upregulation of gap junctions. However, to date, there has been no investigation on the effect of carbon-ion irradiation on electrophysiological properties in human. We investigated this effect in patients with mediastinum extra-cardiac cancer treated with carbon-ion radiotherapy that included irradiating the heart.</AbstractText>In April-December 2009, eight patients were prospectively enrolled (including two male, aged 72.5 ± 13.0 years). They were treated with 44-72 Gray equivalent (GyE), with their hearts exposed to 1.3-19.1 GyE. High-resolution ambulatory electrocardiography was performed before and after radiotherapy to investigate arrhythmic events, late potentials (LPs), and heart rate variability. Five patients had pre-existing premature ventricular contraction (PVC)/atrial contraction (PAC) or paroxysmal atrial fibrillation (PAF)/AF; after irradiation, this improved in four patients with PVC/PAF/AF and did not deteriorate in one patient with PAC. Ventricular LP findings did not deteriorate and improved in one patient. In eight cases with available atrial LP findings, there was no deterioration, and two patients showed improvements. The low frequency/high frequency ratio of heart rate variability improved or did not deteriorate in the six patients who received radiation exposure to the bilateral stellate ganglions. During the five-year follow-up for the prognosis, six of the eight patients died because of cancer; there was no history of hospitalization for cardiac events.</AbstractText>Although this preliminary study has several limitations, carbon-ion beam irradiation to the heart is not immediately cardiotoxic and demonstrates consistent signals of arrhythmia reduction.</AbstractText>© 2017 Wiley Periodicals, Inc.</CopyrightInformation> |
20,448 | Implantable Cardioverter-Defibrillator Therapy in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy: Predictors of Appropriate Therapy, Outcomes, and Complications. | Arrhythmogenic right ventricular dysplasia/cardiomyopathy is characterized by ventricular arrhythmias and sudden cardiac death. Once the diagnosis is established, risk stratification to determine whether implantable cardioverter-defibrillator (ICD) placement is warranted is critical.</AbstractText>The cohort included 312 patients (163 men, age at presentation 33.6±13.9 years) with definite arrhythmogenic right ventricular dysplasia/cardiomyopathy who received an ICD. Over 8.8±7.33 years, 186 participants (60%) had appropriate ICD therapy and 58 (19%) had an intervention for ventricular fibrillation/flutter. Ventricular tachycardia at presentation (hazard ratio [HR]: 1.86; 95% confidence interval [CI], 1.38-2.49; P</i><0.001), inducibility on electrophysiology study (HR: 3.14; 95% CI, 1.95-5.05; P</i><0.001), male sex (HR: 1.62; 95% CI, 1.20-2.19; P</i>=0.001), inverted T waves in ≥3 precordial leads (HR: 1.66; 95% CI, 1.09-2.52; P</i>=0.018), and premature ventricular contraction count ≥1000/24 hours (HR: 2.30; 95% CI, 1.32-4.00; P</i>=0.003) were predictors of any appropriate ICD therapy. Inducibility at electrophysiology study (HR: 2.28; 95% CI, 1.10-4.70; P</i>=0.025) remained as the only predictor after multivariable analysis. The predictors for ventricular fibrillation/flutter were premature ventricular contraction ≥1000/24 hours (HR: 4.39; 95% CI, 1.32-14.61; P</i>=0.016), syncope (HR: 1.85; 95% CI, 1.10-3.11; P</i>=0.021), aged ≤30 years at presentation (HR: 1.76; 95% CI, 1.04-3.00; P</i><0.036), and male sex (HR: 1.73; 95% CI, 1.01-2.97; P</i>=0.046). Younger age at presentation (HR: 3.14; 95% CI, 1.32-7.48; P</i>=0.010) and high premature ventricular contraction burden (HR: 4.43; 95% CI, 1.35-14.57; P</i><0.014) remained as independent predictors of ventricular fibrillation/flutter. Complications occurred in 66 participants (21%), and 64 (21%) had inappropriate ICD interventions. Overall mortality was low at 2%, and 4% underwent heart transplantation.</AbstractText>These findings represent an important step in identifying predictors of ICD therapy for potentially fatal ventricular fibrillation/flutter and should be considered when developing a risk stratification model for arrhythmogenic right ventricular dysplasia/cardiomyopathy.</AbstractText>© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.</CopyrightInformation> |
20,449 | Make it two: A case report of dual sequential external defibrillation. | ABSTRACTDual sequential external defibrillation (DSED) is the process of near simultaneous discharge of two defibrillators with differing pad placement to terminate refractory arrhythmias. Previously used in the electrophysiology suite, this technique has recently been used in the emergency department and prehospital setting for out-of-hospital cardiac arrest (OHCA). We present a case of successful DSED in the emergency department with neurologically intact survival to hospital discharge after refractory ventricular fibrillation (RVF) and review the putative mechanisms of action of this technique. |
20,450 | The association of QRS duration with atrial fibrillation in a heart failure with preserved ejection fraction population: a pilot study. | Heart failure is a significant cause of morbidity and mortality, yet patient risk stratification may be difficult. Prevention or treatment of atrial fibrillation (AF) may be an important strategy in these patients that could positively affect their outcome. It has been demonstrated that in patients with systolic dysfunction, prolonged QRS duration (QRSd), an easily measured electrocardiographic parameter, is associated with AF.</AbstractText>Prolonged QRSd is associated with an increase in prevalence of AF in patients with heart failure with preserved ejection fraction(HFPEF).</AbstractText>Between February 2006 and February 2009, 718 patients were discharged with a diagnosis of HF from the Dartmouth-Hitchcock Medical Center. Of these, 206 had EF ≥50% by echocardiography performed within 72 hours of admission. After exclusions, 82 patients remained, of which 25 had AF and 57 had sinus rhythm. Characteristics of the AF and sinus-rhythm patients were compared in this pilot study.</AbstractText>After adjustment for age, prior diagnosis of HF, and left atrial area, there was a nonsignificant trend (odds ratio: 2.2, 95% CI of 0.3-17.2) for a QRSd >120 ms to be associated with AF.</AbstractText>Similar to results in patients with systolic dysfunction, patients with preserved EF may have an association between a prolonged QRSd and AF.</AbstractText>© 2017 Wiley Periodicals, Inc.</CopyrightInformation> |
20,451 | Classification of normal and arrhythmic ECG using wavelet transform based template-matching technique. | To propose a wavelet-based template matching technique to extract features for automatic classification of electrocardiogram signals of normal and arrhythmic individuals.</AbstractText>The study was conducted from December 2014 to December 2015 at the Department of Electrical Engineering, Institute of Space Technology, Islamabad, Pakistan. Electrocardiogram signals analysed in this study were taken from the freely available database www.physionet.org. The data for normal subjects was taken from the Massachusetts Institute of Technology-Beth Israel Hospital's normal sinus rhythm database and data for diseased subjects was taken from the arrhythmia database.</AbstractText>Of the 30 subjects, there were 15(50%) normal and 15(50%) diseased subjects. The group-averaged phase difference indices of arrhythmic subjects were significantly larger than that of normal individuals (p<0.05) within the frequency range of 0.9-1.1 Hz. Moreover, the scatter plot between the phase difference index and magnitude of wavelet cross-spectrum for frequency range of 0.9-1.1 Hz demonstrated a satisfactory delineation between normal and arrhythmic individuals.</AbstractText>Wavelet decomposition-based template matching technique achieved satisfactory delineation of normal and arrhythmic electrocardiogram dynamics.</AbstractText> |
20,452 | <sup>18</sup>F-FDG-PET in Finnish patients with clinical suspicion of cardiac sarcoidosis: Female sex and history of atrioventricular block increase the prevalence of positive PET findings. | Fluorodeoxyglucose positron emission tomography (FDG-PET) is a non-invasive imaging modality that has been shown to be a feasible method to demonstrate myocardial inflammation. The aim of this study was to identify the patients suspected of having cardiac sarcoidosis (CS), who are most likely to benefit from PET imaging.</AbstractText>137 patients suspected of having CS underwent a dedicated cardiac FDG-PET examination at Tampere University Hospital between August 2012 and September 2015. These examinations were retrospectively analyzed.</AbstractText>33 and 12 of the 137 patients had abnormal left and right ventricular (LV and RV) FDG-uptake, respectively. Abnormal LV-uptake and RV-uptake were significantly associated with female sex and a history of advanced AV-block (P < 0.05). Abnormal RV-uptake was also associated with ventricular tachycardia and atrial fibrillation (P < 0.05). 56% of the 27 female patients with a history of AV-block had a pathological PET finding compared to only 6% of the 49 male patients without a history of AV-block. There were 17 female patients with history of both AV-block and ventricular tachycardia, 71% of them had abnormal PET finding.</AbstractText>Abnormal FDG-PET findings were associated with female sex, AV-block, and arrhythmias in this clinical cohort.</AbstractText> |
20,453 | Pretreatment with intravenous amiodarone improves the efficacy of ibutilide treatment on cardioversion rate and maintenance time of sinus rhythm in patients with persistent atrial fibrillation. | The aim of the present study was to assess the efficacy and safety of the pharmacological conversion of persistent atrial fibrillation (AF) using amiodarone or/and ibutilide. Seventy-nine consecutive patients (48 males and 31 females; mean age, 64.6±11.2 years; range, 40-80 years) with non-valvular chronic AF lasting >7 days (range, 7-97 days) that were admitted to hospital for elective pharmacological cardioversion were randomly assigned to receive treatment with intravenous ibutilide (1 mg plus an additional 1 mg if required; n=39) or intravenous amiodarone (300 mg) plus intravenous ibutilide (1 mg; n=40). Success rates of cardioversion were 51.3% (20/39 patients) for ibutilide alone and 71.8% (28/39 patients) for amiodarone + ibutilide (P<0.05). A comparable increase in the QTc interval was observed in the two groups. It was observed that the co-administration of amiodarone and ibutilide was safer than ibutilide alone with regard to the risk of ventricular arrhythmia. Forty-eight patients of successful cardioversion were personally contacted for follow-up. The result indicated that the sinus rhythm maintenance time of the amiodarone + ibutilide group (4.36±2.44 months) was significantly higher than that of the ibutilide group (2.34±1.75 months; P<0.01). In conclusion, pretreatment with intravenous amiodarone + ibutilide for pharmacological cardioversion of persistent AF is considered to be more effective and safer than treatment with ibutilide alone. |
20,454 | Variations of Postresuscitation Lung Function after Thrombolysis Therapy in a Cardiac Arrest Porcine Model Caused by Pulmonary Thromboembolism. | Study of lung function in survivor from cardiac arrest (CA) caused by pulmonary thromboembolism (PTE) was rare. The aim of this study was to investigate the variations of postresuscitation lung function after thrombolysis treatment in a CA porcine model caused by PTE.</AbstractText>After 2 min of untreated CA, pigs of 10-12 weeks with a weight of 30 ± 2 kg (n = 24) were treated with recombinant human tissue plasminogen activator (50 mg). Cardiopulmonary resuscitation (CPR) and ventilation were initiated after drug administration. Pulmonary function and arterial blood gas parameters were measured at baseline, return of spontaneous circulation (ROSC) immediately, and 1 h, 2 h, 4 h, and 6 h after ROSC.</AbstractText>The dynamic lung compliance decreased significantly at ROSC immediately and 1 h after ROSC compared to baseline (21.86 ± 2.00 vs. 26.72 ± 2.20 ml/mmHg and 20.38 ± 1.31 vs. 26.72 ± 2.20 ml/mmHg, respectively; P < 0.05; 1 mmHg = 0.133 kPa). Compared with baseline, airway resistance increased significantly at ROSC immediately and 1 h after ROSC (P < 0.05). Respiratory index also increased after ROSC and showed significant differences among baseline, ROSC immediately, and 2 h after ROSC (P < 0.05). Oxygen delivery decreased at ROSC immediately compared to baseline (P < 0.05). The oxygenation index decreased significantly at any time after ROSC compared to baseline (P < 0.05). Extravascular lung water index and pulmonary vascular permeability index (PVPI) showed significant differences at ROSC immediately compared to baseline and 1 h after ROSC (P < 0.05); PVPI at ROSC immediately was also different from 6 h after ROSC (P < 0.05). Ventilation/perfusion ratios increased after ROSC (P < 0.05). Histopathology showed fibrin effusion, bleeding in alveoli, and hemagglutination in pulmonary artery.</AbstractText>Lung function remains abnormal even after CPR with thrombolysis therapy; it is essential to continue anticoagulation and symptomatic treatment after ROSC.</AbstractText> |
20,455 | <i>SCN5A</i> Genetic Polymorphisms Associated With Increased Defibrillator Shocks in Brugada Syndrome. | Brugada syndrome (BrS) is an inherited primary arrhythmia disorder leading to sudden cardiac arrest. SCN5A</i>, encoding the α-subunit of the cardiac sodium channel (Nav1.5), is the most common pathogenic gene of BrS. An implantable cardioverter defibrillator (ICD) is the standard treatment for secondary prevention. This study aimed to evaluate association of the SCN5A</i> variant with this cardiac conduction disturbance and appropriate ICD shock therapy in Thai symptomatic BrS patients with ICD implants.</AbstractText>Symptomatic BrS patients diagnosed at university hospital were enrolled from 2008 to 2011. The primary outcome of the study was an appropriate ICD shock defined as having non-pacing-associated ICD shock after the occurrence of ventricular tachycardia or ventricular fibrillation. Associations between SCN5A</i> polymorphisms, cardiac conduction disturbance, and potential confounding factors associated with appropriate ICD shock therapy were analyzed. All 40 symptomatic BrS patients (median age, 43 years) with ICD implantations were followed for 24 months. There were 16 patients (40%) who had the appropriate ICD shock therapy after ICD treatment. An independent factor associated with appropriate ICD shock therapy was SCN5A-</i>R1193Q with an adjusted hazard ratio of 10.550 (95% CI, 1.631-68.232).</AbstractText>SCN5A-</i>R1193Q is associated with cardiac conduction disturbances. It may be a genetic marker associated with ventricular arrhythmia leading to appropriate ICD shock therapy in symptomatic BrS patients with ICD treatment. Because of the small sample size of study population and the appropriate ICD shock outcome, further large studies are needed to confirm the results of this study.</AbstractText>© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.</CopyrightInformation> |
20,456 | Detection and quantification of gasping during resuscitation for out-of-hospital cardiac arrest. | To detect and quantify gasping during cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrest (OHCA) patients and to investigate whether gasping is associated with increased return of spontaneous circulation (ROSC).</AbstractText>A prospective observational study in patients resuscitated and mechanically or manually ventilated for OHCA by emergency physicians of Ghent University Hospital. After intubation, pressure catheters were inserted in the endotracheal tube (ETT) and pressures were measured at the proximal and distal ends of the ETT. Gasping was analysed with custom-developed software and volumes were calculated based on pressure differences between the catheters. Data are expressed as median (interquartile range).</AbstractText>Data were collected in 292 resuscitated patients of whom 36.2% achieved ROSC. Seventy-six of 292 (26.0%) patients showed gasping on the pressure curves during resuscitation. The median gasping volume was 274ml (196-434). The median gasping rate was 3.7 gasps/min (1.5-7.3). Gasping occurred significantly more in patients displaying ventricular fibrillation as the initial rhythm compared to patients with pulseless electrical activity, pulseless ventricular tachycardia or asystole. The median gasping rate was significantly higher in the ROSC group compared to the non-ROSC group (11.8 gasps/min (95% CI [4.2, 13.9]) and 2.8 gasps/min (95% CI [1.7, 3.9]) respectively (P<0.001)). A gasping rate of >7.3 gasps/min appeared to be the optimal criterion value to herald ROSC. Deeper negative pressures were associated with an increased incidence of ROSC (P=0.011). There was no significant difference in ROSC between patients with gasping and those without.</AbstractText>The occurrence of gasping during CPR was high. Significant gasping volumes were measured. The presence or absence of gasping was not associated with ROSC, but higher gasping rate and deeper negative pressures were.</AbstractText>Copyright © 2017 Elsevier B.V. All rights reserved.</CopyrightInformation> |
20,457 | Regional Variation in Outcomes of Hospitalized Patients Having Out-of-Hospital Cardiac Arrest. | The aim of this study was to investigate patient outcomes after hospitalization for out-of-hospital cardiac arrest in the United States. We used the 2002 to 2013 Nationwide Inpatient Sample database to identify adults ≥18 years with an International Classification of Diseases, Ninth Revision, Clinical Modification, principal diagnosis code of cardiorespiratory arrest (427.5) or ventricular fibrillation (VF) (427.41). In 4 predefined federal geographic regions: Northeast, Midwest, South, and West, means and proportions of survival, survival stratified by initial rhythm, hospital charges, and cost were estimated. Multiple linear and logistic regression models were conducted. Of the 154,177 patients with out-of-hospital cardiac arrest hospitalized in the United States, 25,873 (16.8%) were in the Northeast, 38,296 (24.8%) in the Midwest, 57,305 (37.2%) in the South, and 32,703 (21.2%) in the West. Variability in survival was noted in VF arrests; compared with the Northeast, survival was higher in the Midwest and South (adjusted odds ratio [AOR] 1.16, 95% confidence interval [CI] 1.02 to 1.32 and AOR 1.24, 95% CI 1.09 to 1.40, respectively), with no difference detected in the West (AOR 0.93, 95% CI 0.82 to 1.06). No variability in survival was noted after non-VF arrests (p >0.05). Hospital charges rose significantly across all regions of the United States (p-trend < 0.001) and were higher in the West compared with the Northeast (hospital charges >$109,000/admission, AOR 1.76; 95% CI 1.50 to 2.06). In conclusion, nationwide, we observed significant regional variability in survival of hospitalized patients after out of hospital VF cardiac arrest, no survival variability after non-VF arrests, and a steady increase in hospital charges. |
20,458 | Enterobacter cloacae-Related Necrotizing Fasciitis After Peritoneal Dialysis in Delayed Graft Function: A Case Report. | Necrotizing fasciitis is an uncommon soft-tissue infection that involves the superficial fascia, subcutaneous fat, and deep fascia. Herein, we report the first case of Enterobacter cloacae-related necrotizing fasciitis after peritoneal dialysis in delayed graft function.</AbstractText>A 58-year-old man, who was a hepatitis B-viral carrier and had atrial fibrillation, received cadaveric renal transplantation with peritoneal dialysis and encountered delayed graft function. On postoperative day 5, we tried hemodialysis via the right jugular dialysis catheter. However, he was unable to endure the hemodynamic changes during hemodialysis, showing rapid ventricular rhythm on electrocardiography. On postoperative day 7, we changed to peritoneal dialysis. However, he presented with fever and pain on his left flank and lower extremity. His white blood cell count and C-reactive protein levels were suddenly elevated. According to the abdomen computed tomography scan, there were subcutaneous fluid and air in the left flank and anterolateral pelvic wall. We performed peritoneal dialysis catheter removal, debridement, and drainage of the left external oblique muscle fascia. In a culture, Enterobacter cloacae was identified. After receiving meropenem for 2 months, his wound healed and delayed graft function was recovered.</AbstractText>Peritoneal dialysis of delayed graft function seems to be effective in reducing the incidence and severity of delayed recovery of renal function after renal transplantation in some reports. However, it is necessary to be cautious when dealing with a rapidly developing and life-threatening soft-tissue infection, such as necrotizing fasciitis. To reduce mortality rates, early diagnosis, recurrent surgical debridement, and aggressive therapy are mandatory.</AbstractText>Copyright © 2017 Elsevier Inc. All rights reserved.</CopyrightInformation> |
20,459 | ABO blood groups: A risk factor for left atrial and left atrial appendage thrombogenic milieu in patients with non-valvular atrial fibrillation. | Previous studies have identified ABO blood groups as predictors of thromboembolic diseases. In patients with atrial fibrillation (AF), however, potential association between ABO blood groups and the risk of left atrial (LA) and/or left atrial appendage (LAA) thrombogenic milieu (TM) has not been established.</AbstractText>This is a retrospective case-control study that included 125 consecutive patients with non-valvular atrial fibrillation (NVAF) plus TM, as evidenced by transesophageal echocardiography (TEE) during a period from1 January 2010 to 31 December 2016. The controls were selected randomly from 1072 NVAF without TM at a 1:2 ratio. Potential association between ABO blood groups and TM was analyzed using multivariate logistic regression analysis.</AbstractText>The risk of TM was higher in patients with blood group A (33.6% vs. 20.2% in non-A blood groups, P=0.005). After adjusting for age, sex, oral anticoagulant use, AF type and duration, and relevant functional measures (e.g., NT-pro BNP level, left atrium diameter, and left ventricular ejection fraction), blood group A remained associated with an increased risk of TM (OR=2.99, 95% CI 1.4-6.388, P=0.005).</AbstractText>Blood group A is an independent risk factor for TM in NVAF patients.</AbstractText>Copyright © 2017 Elsevier Ltd. All rights reserved.</CopyrightInformation> |
20,460 | Early regional wall distension is strongly associated with vulnerability to ventricular fibrillation but not arrhythmia triggers following coronary occlusion in vivo. | Wall stress may favor ischemic ventricular arrhythmias, yet its association with ventricular fibrillation (VF) or ventricular ectopy has been inconsistent among studies and its potential arrhythmogenicity across the cardiac cycle is unclear. In 91 open-chest pigs undergoing 40-50 min left anterior descending artery occlusion, we assessed the association between diastolic or systolic distension of the ischemic area and the incidence of ventricular premature beats (VPBs) and VF. End-diastolic segment length (EDL) and systolic bulging ([maximum systolic length-EDL] × 100/EDL) were measured by ultrasonic crystals. Fifteen minutes after occlusion, EDL increased to 112.7 ± 5.6% of baseline (P < 0.001) and systolic bulging averaged 3.4 ± 2.2%. Median VPB number was 52 (IQR, 16-110), 2 (0-7) in phase Ia and 49 (13-94) in phase Ib. VF occurred in 26 animals (28.6%), the first episode appearing 24 ± 6 min after occlusion. EDL increase was associated with subsequent VF (115.9 ± 5.7 and 111.4 ± 5.1% in animals with and without VF, P < 0.001) and with the number of VF episodes (P = 0.001) but not with VPB number, overall (r = 0.028, P = 0.801) or in phases Ia or Ib. Systolic bulging was related neither to VF occurrence (3.2 ± 2.2 and 3.5 ± 2.2%, respectively, P = 0.561) nor to VBP number (r = 0.095, P = 0.397). EDL increase predicted VF after adjusting for ischemic area size and K<sup>+</sup> levels (odds ratio for 1% increase: 1.17, 95%CI 1.06-1.29, P = 0.001). Thus, diastolic regional ventricular distension predicts VF occurrence after coronary occlusion whereas neither diastolic nor systolic distension is associated with ventricular ectopy, which suggests that distension favors VF by acting on the arrhythmic substrate but not on arrhythmia triggers. |
20,461 | Prognostic Implications of Left Ventricular Global Longitudinal Strain in Predialysis and Dialysis Patients. | Chronic kidney disease (CKD) is a worldwide growing epidemic associated with an increased risk of cardiovascular morbidity and mortality. Left ventricular (LV) global longitudinal strain (GLS) is a measure of LV systolic function associated with prognosis in the general population. However, little is known about the association between LV GLS and survival in patients with CKD. The aim of the present study was to investigate the prognostic implications of LV GLS in predialysis and dialysis patients specifically. LV GLS was measured in a retrospective cohort of predialysis and dialysis patients (CKD stage 3b to 5) who underwent clinically indicated echocardiography between 2004 and 2015. Patients were divided into 4 groups according to quartiles of LV GLS: first quartile (LV GLS ≤10.6%, worst function), second quartile (LV GLS 10.7% to 15.1%), third quartile (LV GLS 15.2% to 17.8%), and fourth quartile (LV GLS ≥17.9%, best function). The primary end point was all-cause mortality. Of 304 patients (62 ± 14 years, 66% male), 65% were in predialysis and 35% in dialysis. During a median follow-up of 29 months (interquartile range 16 to 58 months), 34% of patients underwent renal transplantation and 36% died. Patients with LV GLS ≤10.6% showed significantly worse prognosis compared with the other groups (log-rank test, p <0.001). LV GLS ≤10.6% was significantly associated with increased risk of all-cause mortality (hazard ratio 2.18, 95% CI 1.17 to 4.06, p = 0.014) after correcting for age, gender, albumin levels, atrial fibrillation, and renal transplantation. In conclusion, in predialysis and dialysis patients, severely impaired LV GLS is independently associated with an increased risk of mortality. |
20,462 | Modular minimal invasive extracorporeal circuits: another step toward universal applicability? | Safety concerns have been one of the main reasons opposing a wider acceptance of minimal invasive extracorporeal circuits (MiECC). Following an extensive experience and a multitude of modifications, we have set out to employ a modular MiECC as a universal extracorporeal circuit.</AbstractText>A total of 129 cardiac surgical procedures were performed by a single surgeon in 2013. Excluding procedures done under circulatory arrest or with the potential need of such, the MiECC was utilized in almost 90% of surgeries. Of sixty-two (simple procedures) patients who underwent coronary artery bypass grafting (CABG), aortic valve replacement (AVR) or CABG + AVR, 82% were non-elective, 10% had a left ventricular ejection fraction (EF) <30% and most had an impaired renal function. Thirty-eight patients had more complex surgeries (complex procedures), 37% of which were urgent, 15% had an EF <30% and the majority had renal dysfunction.</AbstractText>The 30-day mortality was 5% in simple procedures and 2.5% in complex procedures. The incidence of postoperative atrial fibrillation was 13% and 16%, respectively. Optimum outcome was defined as a freedom from all complications and blood transfusions and was achieved in 52% and 42%, respectively.</AbstractText>This report shows that modular MiECC can be employed with a high safety margin in cardiac surgery. Furthermore, it emphasizes the impact that minimal invasive philosophy could have in improving patient care.</AbstractText> |
20,463 | A Potential Role of Esophageal Cancer Related Gene-4 for Atrial Fibrillation. | Epidemiological studies have shown a strong correlation between tumor and AF. However, the molecular link between tumor and AF remains unknown. ECRG4, a tumor suppressor gene that is expressed in the A-V node and in sporadic ventricular myocytes, inhibits tumorigenesis and monitors tissue homeostasis by functioning as a 'sentinel' molecule gauging inflammatory and cell proliferative responses. To explore the potential physiological function of Ecrg4 in heart, we evaluated its distribution in heart, analyzed its expression in patients with persistent AF and in a canine AF model, and dissected the molecular events downstream of Ecrg4. The results showed that the level of Ecrg4 expression is homogenously high in atria and the conduction systems and in sporadic ventricular myocytes. Importantly, the expression of Ecrg4 was significantly decreased in atrial appendages of AF patients than patients with SR. Moreover, in rapid pacing canine AF models, the expression of ECRG4 in atria was significantly decreased compared to that of the controls. Mechanistically, knockdown ECRG4 in atrial myocytes significantly shortened the APDs, inhibited the expression of Gja1, and activated pro-inflammatory cascades and genes involved in cardiac remodeling. These results suggest that Ecrg4 may play a critical role in the pathogenesis of AF. |
20,464 | Electrocardiographic Preexcitation and Risk of Cardiovascular Morbidity and Mortality: Results From the Copenhagen ECG Study. | The majority of available data on the clinical course of patients with ventricular preexcitation in the ECG originates from tertiary centers. We aimed to investigate long-term outcomes in individuals from a primary care population with electrocardiographic preexcitation.</AbstractText>Digital ECGs from 328 638 primary care patients were collected during 2001 to 2011. We identified 310 individuals with preexcitation (age range, 8-85 years). Data on medication, comorbidity, and outcomes were collected from Danish nationwide registries. The median follow-up time was 7.4 years (quartiles, 4.6-10.3 years). Compared with the remainder of the population, patients with preexcitation had higher adjusted hazards of atrial fibrillation (hazard ratio [HR], 3.12; 95% confidence interval [CI], 2.07-4.70) and heart failure (HR, 2.11; 95% CI, 1.27-3.50). Subgroup analysis on accessory pathway location revealed a higher adjusted hazard of heart failure for a right anteroseptal accessory pathway (HR, 5.88; 95% CI, 2.63-13.1). There was no evidence of a higher hazard of death among individuals with preexcitation when looking across all age groups (HR, 1.07; 95% CI, 0.68-1.68). However, a statistically significant (P</i>=0.01) interaction analysis (<65 versus ≥65 years) indicated a higher hazard of death for patients with preexcitation ≥65 years (HR, 1.85; 95% CI, 1.07-3.18).</AbstractText>In this large ECG study, individuals with preexcitation had higher hazards of atrial fibrillation and heart failure. The higher hazard of heart failure seemed to be driven by a right anteroseptal accessory pathway. Among elderly people, we found a statistically significant association between preexcitation and a higher hazard of death.</AbstractText>© 2017 American Heart Association, Inc.</CopyrightInformation> |
20,465 | Early changes in atrial conduction times in hypertensive patients with elevated pulse pressure. | Pulse pressure (PP) is the difference between systolic and diastolic blood pressure, and is an independent predictor of atrial fibrillation (AF). In this study we investigated the relationship between PP and atrial conduction times.</AbstractText>The study included 157 patients with essential hypertension. PP of 60 mmHg or more was regarded as elevated (n=56). Atrial electromechanical delay (EMD) was assessed with tissue Doppler echocardiography and P-wave dispersion (Pd) was calculated from the electrocardiogram.</AbstractText>Left atrial volume index (23.6±4.9 ml/m2</sup> vs. 25.2±6.5 ml/m2</sup>, p=0.141), left ventricular mass index (77.3±13.5 g/m2</sup> vs. 80.9±19.6 g/m2</sup>, p=0.180) and grade I diastolic dysfunction (42% vs. 53%, p=0.242) were similar between groups. Inter-atrial (33.6±9.2 ms vs. 41.5±11.3 ms, p<0.001), intra-left atrial (23.0±8.8 ms vs. 28.2±10.6 ms, p=0.001) and intra-right atrial (10.5±5.8 ms vs. 13.2±4.9 ms, p=0.004) EMD were found to be higher in patients with elevated PP. P-maximum (108±8 ms vs. 114±9 ms, p<0.001) and Pd (30±13 ms vs. 38±13 ms, p<0.001) were also prolonged in patients with elevated PP. Multivariate linear regression analysis revealed that PP was independently associated with inter-atrial EMD (β=0.379, t=4.088, p<0.001).</AbstractText>This study showed that elevated PP is associated with prolonged atrial EMD and Pd. Atrial conduction is disturbed in hypertensive patients with elevated PP before the development of significant structural remodeling.</AbstractText>Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.</CopyrightInformation> |
20,466 | Using Simulation as an Investigational Methodology to Explore the Impact of Technology on Team Communication and Patient Management: A Pilot Evaluation of the Effect of an Automated Compression Device. | This pilot study used a simulation-based platform to evaluate the effect of an automated mechanical chest compression device on team communication and patient management.</AbstractText>Four-member emergency department interprofessional teams were randomly assigned to perform manual chest compressions (control, n = 6) or automated chest compressions (intervention, n = 6) during a simulated cardiac arrest with 2 phases: phase 1 baseline (ventricular tachycardia), followed by phase 2 (ventricular fibrillation). Patient management was coded using an Advanced Cardiovascular Life Support-based checklist. Team communication was categorized in the following 4 areas: (1) teamwork focus; (2) huddle events, defined as statements focused on re-establishing situation awareness, reinforcing existing plans, and assessing the need to adjust the plan; (3) clinical focus; and (4) profession of team member. Statements were aggregated for each team.</AbstractText>At baseline, groups were similar with respect to total communication statements and patient management. During cardiac arrest, the total number of communication statements was greater in teams performing manual compressions (median, 152.3; interquartile range [IQR], 127.6-181.0) as compared with teams using an automated compression device (median, 105; IQR, 99.5-123.9). Huddle events were more frequent in teams performing automated chest compressions (median, 4.0; IQR, 3.1-4.3 vs. 2.0; IQR, 1.4-2.6). Teams randomized to the automated compression intervention had a delay to initial defibrillation (median, 208.3 seconds; IQR, 153.3-222.1 seconds) as compared with control teams (median, 63.2 seconds; IQR, 30.1-397.2 seconds).</AbstractText>Use of an automated compression device may impact both team communication and patient management. Simulation-based assessments offer important insights into the effect of technology on healthcare teams.</AbstractText> |
20,467 | Telemetry Monitor Watchers Reduce Bedside Nurses' Exposure to Alarms by Intercepting a High Number of Nonactionable Alarms. | Cardiac telemetry, designed to monitor hospitalized patients with active cardiac conditions, is highly utilized outside the intensive care unit but is also resource-intensive and produces many nonactionable alarms. In a hospital setting in which dedicated monitor watchers are set up to be the first responders to system-generated alerts, we conducted a retrospective study of the alerts produced over a continuous 2-month period to evaluate how many were intercepted before nurse notification for being nonactionable, and how many resulted in code team activations. Over the 2-month period, the system generated 20,775 alerts (5.1/patient-day, on average), of which 87% were intercepted by monitor watchers. None of the alerts for asystole, ventricular fibrillation, or ventricular tachycardia resulted in a code team activation. Our results highlight the high burden of alerts, the large majority of which are nonactionable, as well as the role of monitor watchers in decreasing the alarm burden on nurses. Measures are needed to decrease telemetry-related alerts in order to reduce alarm-related harms, such as alarm fatigue. Journal of Hospital Medicine 2017;12:447-449. |
20,468 | Cardiac Arrhythmias in Patients with Exacerbation of COPD. | Supraventricular and ventricular arrhythmias are common among patients with chronic obstructive pulmonary disease (COPD). Multiple factors can contribute to the development of arrhythmias in patients with exacerbation of the disease, including: respiratory or heart failure, hypertension, coronary disease and also medications. In the present study we seek to determine the prevalence of cardiac arrhythmias and risk factors among patients with exacerbation of COPD. The study was a retrospective evaluation of 2753 24-h Holter recordings of patients hospitalized in 2004-2016. Exacerbation of COPD was diagnosed in 152 patients and the prevalence of arrhythmias in this group of patients was 97%. The commonest arrhythmia was ventricular premature beats (VPB) - 88.8%, followed by supraventricular premature beats (SPB) - 56.5%. Permanent atrial fibrillation accounted for 30.3% and paroxysmal atrial fibrillation (PAF) for 12.5%. Supraventricular tachycardia (SVT) was noted in 34.2% patients and ventricular tachycardia in 25.6%. Respiratory failure increased the risk of SPB, while heart failure increased the risk of VPB. Treatment with theophylline was associated with a higher proportion of PAF and SVT. In conclusion, COPD exacerbation is associated with a high prevalence of cardiac arrhythmias. COPD treatment and comorbidities increase the risk of arrhythmias. |
20,469 | Acute Respiratory Distress Syndrome Complicated by Amiodarone Induced Pulmonary Fibrosis: Don't Let Your Guard Down. | Amiodarone is an antiarrhythmic agent which is commonly used to treat both supraventricular and ventricular arrhythmias. This iodine containing compound has been associated with several adverse events like it tends to accumulate in several organs. Among those, the most serious is Amiodarone Pulmonary Toxicity (APT). While the incidence of this complication has decreased with the use of lower doses of amiodarone but it can occur with any dose. Pulmonary complications usually present as an acute or subacute pneumonitis. On chest X-ray and high-resolution Computed Tomography (CT), diffuse infiltrates were found. Here, we present a case in which acute respiratory distress syndrome like features were detected which got subsided after stopping tablet amiodarone. The patient was a known case of atrial fibrillation for which she was taking tablet amiodarone for the last six months. |
20,470 | Mitral valve repair for degenerative mitral valve disease: surgical approach, patient selection and long-term outcomes. | Mitral valve repair (MVRepair) has become the procedure of choice to correct severe degenerative mitral regurgitation (MR), due to its documented superiority to valve replacement regarding long-term survival, freedom from valve-related adverse events and preservation of left ventricular (LV) function. The refinement of MVRepair techniques has rendered almost all valves (more than 95%) amenable to repair with a 15-year freedom from reoperation of 90%. The concept of 'centres of excellence for MVRepair' has emerged, encouraging referring doctors to select the most experienced institutions or individual surgeons to deal with the most complex cases, based on repair volume, appropriate peri-procedural imaging and data regarding expected outcomes (repair, mortality and durability of repair). Based on the good results, operating on asymptomatic patients with severe MR is now widely accepted, prophylactically avoiding the dire consequences of chronic MR, such as LV function deterioration/enlargement, and development of atrial fibrillation and pulmonary hypertension. In reference centres, where the repair rate is over 95% for all types of disease with <1% mortality, it has become standard practice in nearly 50%-60% of all patients submitted to MVRepair. Finally, recent advances in the surgical treatment with the purpose of reducing invasiveness and surgical trauma, through partial sternotomy or mini-thoracotomy (video-assisted with or without robotics), are now being increasingly performed in 20%-30% of centres, claiming comparable results to conventional surgery. In addition, transcatheter technology, particularly the MitraClip, is evolving and treading its way in the treatment of high-risk patients with severe MR, but the results are still short of ideal. |
20,471 | Clinical and Genetic Diagnosis of Nonischemic Sudden Cardiac Death. | Nonischemic sudden cardiac death (SCD) is predominantly caused by cardiomyopathies and channelopathies. There are many diagnostic tests, including some complex techniques. Our aim was to analyze the diagnostic yield of a systematic diagnostic protocol in a specialized unit.</AbstractText>The study included 56 families with at least 1 index case of SCD (resuscitated or not). Survivors were studied with electrocardiogram, advanced cardiac imaging, exercise testing, familial study, genetic testing and, in some cases, pharmacological testing. Families with deceased probands were studied using the postmortem findings, familial evaluation, and molecular autopsy with next-generation sequencing (NGS).</AbstractText>A positive diagnosis was obtained in 80.4% of the cases, with no differences between survivors and nonsurvivors (P=.53). Cardiac channelopathies were more prevalent among survivors than nonsurvivors (66.6% vs 40%, P=.03). Among the 30 deceased probands, the definitive diagnosis was given by autopsy in 7. A diagnosis of cardiomyopathy tended to be associated with a higher event rate in the family. Genetic testing with NGS was performed in 42 index cases, with a positive result in 28 (66.6%), with no differences between survivors and nonsurvivors (P=.21).</AbstractText>There is a strong likelihood of reaching a diagnosis in SCD after a rigorous protocol, with a more prevalent diagnosis of channelopathy among survivors and a worse familial prognosis in cardiomyopathies. Genetic testing with NGS is useful and its value is increasing with respect to the Sanger method.</AbstractText>Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.</CopyrightInformation> |
20,472 | Thromboembolism and bleeding risk scores and predictors of cardiac death in a population with atrial fibrillation. | Atrial fibrillation (AF) is a common arrhythmia, with risk of systemic embolism and death. It presents rheumatic etiology in up to 32% of developing countries, whose anticoagulation and evolution data are scarce.</AbstractText>to determine the predictors of cardiac death considering the clinical profile, thromboembolism and bleeding scores of patients with AF of a single center, with high prevalence of rheumatic heart disease.</AbstractText>302 patients with AF were studied, mean age 58.1 years; 161 women; 96 pts with rheumatic etiology. Patients underwent clinical and laboratory evaluation, measurement of risk scores and the mean follow-up of 12.8 months.</AbstractText>174 were using warfarin. The averages of the HAS-BLED and ATRIA scores were 1.4 and 1.2, respectively. Percent time in therapeutic range of international normalized ratio was 45.8%. Thirty patients (9.9%) had cardiac death and 41 had some type of bleeding due to warfarin. By univariate analysis, there was statistical significance between cardiac death and permanent AF, blood pressure, systolic dysfunction, R2CHADS2, CCS, EHRA and HAS-BLED. There was no association with valvular AF. By multivariate analysis, systemic arterial and pulmonary artery pressures, classification CCS and systolic dysfunction showed statistical significance.</AbstractText>There was no association between cardiac death and valvular AF. Independent predictors of cardiac death were low measures of blood pressure, higher score CCS classification and the presence of systolic ventricular dysfunction.</AbstractText> |
20,473 | Hemodynamic instability after pulmonary veins isolation in a patient with dual chamber pacemaker: The phantom injury of the ventricular lead. | The standard treatment of sinus node dysfunction (SND) is the pacemaker implantation, and the ideal methodology for the management of atrial fibrillation (AF) is rhythm control, but this is sometimes very hard to accomplish. For such actions, complete isolation of all pulmonary veins (PVI) is currently widely accepted as the best endpoint.</AbstractText>In this case, we report a female patient, 81 years old, with controlled hypertension, without coronary artery disease, bearer of bilateral knee replacement, and dual chamber pacemaker implanted 1.5 years ago owing to sinus node disease, presenting the following symptoms: presyncope episodes associated with sustained irregular palpitation tachycardia. The evaluation of the pacemaker-recorded episodes of atrial fibrillation, the echocardiogram-presented normal systolic function and measurements, as well as the resting myocardial scintigraphy and with drug use did not demonstrate ischemia and/or fibrosis. The patient was in use of valsartan 320 mg daily, amlodipine 10 mg daily, sotalol hydrochloride 120 mg 2 times daily, and dabigatran 110 mg 2 times daily. At the end of the PVI, the patient presented hemodynamic instability, with a decrease in heart rate to 30 bpm and invasive arterial blood pressure to 60/30 mmHg. The pericardial puncture was quickly carried out with the possibility of cardiac tamponade as the first hypothesis, but no pericardial effusion was found. Next, we detected acute capture loss from the ventricular pacemaker lead, unvarying with high voltage and pulse width, even with stable impedance, sense and keeping the same position visualized by fluoroscopy. And there was soon afterwards induction of sustained ventricular tachycardia degenerating to spontaneous ventricular fibrillation. Electrical cardioversion-defibrillation was performed with 200J, and the sinus rhythm was reestablished, but there was a dead short, and the pacemaker generator was burned and disabled.</AbstractText>So, we can speculate that application of atrial radiofrequency for PVI diffused through the tissues, affecting in some way the tip of the ventricular electrode, causing a microlesion in this structure and making it impossible to capture the right ventricle by the pacemaker. As we cannot see it, we can call it of phantom injury of the ventricular lead.</AbstractText> |
20,474 | Extracorporeal Life Support Increases Survival After Prolonged Ventricular Fibrillation Cardiac Arrest in the Rat. | Extracorporeal life support (ECLS) for cardiopulmonary resuscitation (CPR) may increase end organ perfusion and thus survival when conventional CPR fails. The aim was to investigate, if after ventricular fibrillation cardiac arrest in rodents ECLS improves outcome compared with conventional CPR.</AbstractText>In 24 adult male Sprague-Dawley rats (460-510 g) resuscitation was started after 10 min of no-flow with ECLS (consisting of an open reservoir, roller pump, and membrane oxygenator, connected to cannulas in the jugular vein and femoral artery, n = 8) or CPR (mechanical chest compressions plus ventilations, n = 8) and compared with a sham group (n = 8). After return of spontaneous circulation (ROSC), all rats were maintained at 33°C for 12 h. Survival to 14 days, neurologic deficit scores and overall performance categories were assessed.</AbstractText>ECLS leads to sustained ROSC in 8 of 8 (100%) and neurological intact survival to 14 days in 7 of 8 rats (88%), compared with 5 of 8 (63%) and 1 of 8 CPR rats. The median survival time was 14 days (IQR: 14-14) in the ECLS and 1 day (IQR: 0 to 5) for the CPR group (P = 0.004).</AbstractText>In a rat model of prolonged ventricular fibrillation cardiac arrest, ECLS with mild hypothermia produces 100% resuscitability and 88% long-term survival, significantly better than conventional CPR.</AbstractText> |
20,475 | Association between left atrial function assessed by speckle-tracking echocardiography and the presence of left atrial appendage thrombus in patients with atrial fibrillation. | The aim of the study was to investigate whether the deformation of left atrium (LA) measured by speckle-tracking analysis (STE) is associated with the presence of LA appendage thrombus (LAAT) during non-valvular atrial fibrillation (AF).</AbstractText>Eighty-seven patients (mean age 67 years, 59% men) were included to retrospective cross-sectional study. On top of standard echocardiography we assessed: LA longitudinal systolic strain (LS), systolic (LSSR) and early diastolic strain rate (LESR) in four-chamber and twochamber apical views. All patients underwent transesophageal echocardiography disclosing LAAT in 36 (41%) patients.</AbstractText>Subgroups with and without thrombi did not differ with regard to clinical characteristics. Univariate factors associated with LAAT were as follows: CH2ADS2-VASc Score, left ventricular ejection fraction (LVEF), LV mass, and STE measurements. In a multivariate model only LVEF (p=0.002), LS (p=0.02), LESR (p=0.008), and LSSR (p=0.045) were independently associated with LAAT presence. Moreover, LVEF and LA STE measurements provided incremental value over the CH2ADS2-VASc Score.</AbstractText>Speckle-tracking TTE may be used to describe LA reservoir and conduit function during AF, allowing the identification of patients with higher risk of LAAT and providing incremental value over the CH2ADS2-VASc Score.</AbstractText> |
20,476 | Targeted Temperature Management Effectiveness in the Elderly: Insights from a Large Registry. | Targeted temperature management (TTM) is recommended for all comatose adult out-of-hospital cardiac arrest (OHCA) patients with shockable first documented rhythm. However, studies examining the use and benefits of TTM among patients aged 75 and older are lacking. Using the Cardiac Arrest Registry to Enhance Survival (CARES) dataset registry from 2013 to 2015. Study criteria included being 75 years of age or older, survival to hospital admission, and known in-hospital mortality and CPC (Cerebral Performance Categories Scale) Scores. The study outcomes were in-hospital mortality and poor neurologic outcomes (CPC Scores 3 or 4) at hospital discharge among survivors. Hierarchical logistic regression and propensity score matching were used for multivariable adjustment. Two thousand nine hundred eighty-two patients met study inclusion criteria. One thousand three hundred fifty-seven (45.5%) received TTM in the admitting hospital. Receipt of TTM was more likely among men, those with a shockable first documented rhythm, and those with their event witnessed. There was no significant association with TTM and in-hospital mortality among patients with ventricular fibrillation (odds ratio [OR] = 0.88; 95% confidence interval [CI] [0.62-1.25]), p = 0.487 within the cohort. However, patients with a nonshockable first rhythm receiving TTM had higher odds of in-hospital mortality (p < 0.001). Propensity score results showed a modest association with TTM and increased mortality (OR) = 1.22, 95% CI [1.01-1.47]; p = 0.036 and no association with poor neurologic outcome (OR = 1.18; 95% CI [0.82-1.69]; p = 0.379) in the elderly. TTM is often provided to OHCA patients over age 75 though the benefits, particularly among nonshockable first documented rhythm patients are unclear. A randomized trial is needed to definitively answer who among OHCA event survivors aged 75 and older should receive this treatment. |
20,477 | Antiarrhythmic properties of ivabradine in an experimental model of Short-QT- Syndrome. | The I<sub>f</sub> channel inhibitor ivabradine is recommended for treatment of chronic heart failure. However, ivabradine also inhibits human ether-a-go-go (hERG) mediated potassium currents. The aim of the present study was to assess the electrophysiologic effects of ivabradine in an experimental model of short-QT-syndrome. Twelve rabbit hearts were isolated and Langendorff-perfused. After obtaining baseline data, pinacidil, an I<sub>K-ATP</sub> channel opener, was infused (1 μmol/L). Eight endo- and epicardial monophasic action potentials and a 12-lead ECG showed a significant abbreviation of QT interval (-32 ms, P<.05) and shortening of action potential duration at 90% of repolarization (APD90; -22 ms, P<.05). The shortening of ventricular repolarization was accompanied by a reduction of effective refractory period (ERP; -20 ms, P<.05). Thereafter, hearts were additionally treated with ivabradine (5 μmol/L) leading to an increase of QT interval (+31 ms, P<.05), APD90 (+15 ms, P<.05) as well as of ERP (+38 ms, P<.05) and post-repolarization refractoriness (PRR, +33 ms, P<.05) as compared with sole pinacidil infusion. Under baseline conditions, ventricular fibrillation (VF) was inducible by a standardized pacing protocol including programmed stimulation and burst stimulation in 3 of 12 hearts (6 episodes). After application of 1 μmol/L pinacidil, 6 of 12 hearts were inducible (22 episodes). Additional infusion of 5 μmol/L ivabradine led to a significant suppression of VF. Only two episodes could be induced in 1 of 12 hearts. In the present study ivabradine reversed the electrophysiologic effects of pharmacologically simulated short-QT syndrome. Ivabradine demonstrated antiarrhythmic properties based on an increase of both ERP and PRR. |
20,478 | Reduced right ventricular diameter during cardiac arrest caused by tension pneumothorax - a porcine ultrasound study. | Advanced life support (ALS) guidelines recommend ultrasound to identify reversible causes of cardiac arrest. Right ventricular (RV) dilatation during cardiac arrest is commonly interpreted as a sign of pulmonary embolism. The RV is thus a focus of clinical ultrasound examination. Importantly, in animal studies ventricular fibrillation and hypoxia results in RV dilatation. Tension pneumothorax (tPTX) is another reversible cause of cardiac arrest, however, the impact on RV diameter remains unknown.</AbstractText>To investigate RV diameter evaluated by ultrasound in cardiac arrest caused by tPTX or hypoxia.</AbstractText>Pigs were randomized to cardiac arrest by either tPTX (n = 9) or hypoxia (n = 9) and subsequently resuscitated. Tension pneumothorax was induced by injection of air into the pleural cavity. Hypoxia was induced by reducing tidal volume. Ultrasound images of the RV were obtained throughout the study. Tension pneumothorax was decompressed after the seventh rhythm analysis. The primary endpoint was RV diameter after the third rhythm analysis.</AbstractText>At cardiac arrest the RV diameter was 17 mm (95% CI: 13; 21) in the tPTX group and 36 mm (95% CI: 33; 40) in the hypoxia group (P < 0.01, n = 9 for both). At third rhythm analysis RV diameter was smaller in the tPTX group: 12 mm (95% CI: 7; 16) vs. hypoxia group: 28 mm (25; 32) (P < 0.01). After decompression no difference existed between groups: tPTX 29 mm (95% CI: 23; 34) vs. hypoxia 29 mm (95% CI: 20; 38).</AbstractText>The RV diameter is smaller during cardiopulmonary resuscitation in cardiac arrest caused by tPTX when compared with hypoxia. The difference disappears after tPTX decompression.</AbstractText>© 2017 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.</CopyrightInformation> |
20,479 | Long-term treatment-related morbidity in differentiated thyroid cancer: a systematic review of the literature. | Differentiated thyroid cancer (DTC) occurs in relatively young patients and is associated with a good prognosis and long survival. The management of this disease involves thyroidectomy, radioiodine therapy, and long-term thyroid-stimulating hormone suppression therapy (THST). The long-term effects of the treatment and the interaction between subclinical hyperthyroidism and long-term hypoparathyroidism are poorly understood. This review sought to examine the available evidence.</AbstractText>A PubMed search was carried out using the search terms "Thyroid Neoplasms" AND ("Thyroxine" OR "Hypocalcemia" OR "Thyrotropin"). Original English language articles published in the last 30 years studying the morbidity from thyroid-stimulating hormone (TSH) suppression and hypoparathyroidism following a surgery for DTC were retrieved and reviewed by 2 authors.</AbstractText>Of the 3,000 results, 66 papers including 4,517 patients were selected for the present study. Studies reported on a range of skeletal (included in 34 studies, 1,647 patients), cardiovascular (17 studies, 957 patients), psychological (10 studies, 663 patients), and other outcomes (10 studies, 1,348 patients). Nine of 26 studies on patients who underwent THST showed a reduction in bone density, and 13 of 23 studies showed an increase in bone turnover markers. Skeletal effects were more marked in postmenopausal women. There was no evidence of increased fracture risk, and only little data were available on hypoparathyroidism. Four of five studies showed an increased left ventricular mass index on echocardiography, and one study showed a higher prevalence of atrial fibrillation (AF). There was little difference in basic physiological parameters and limited literature regarding symptoms or significant events. Six studies showed associations between long-term TSH suppression and impaired quality of life. Impaired glucose metabolism and prothrombotic states were also found in DTC patients.</AbstractText>There is limited literature regarding long-term DTC treatment-related morbidity, particularly regarding the effects of long-term hypocalcemia. Most studies have focused on surrogate markers and not on clinical outcomes. A large prospective study on defined clinical outcomes would help characterize the morbidity of treatment and stimulate research on tailoring treatment strategies.</AbstractText> |
20,480 | Ranolazine Facilitates Termination of Ventricular Tachyarrhythmia Associated With Acute Myocardial Ischemia Through Suppression of Late I<sub>Na</sub>-Mediated Focal Activity. | Ventricular tachycardia/fibrillation (VT/VF) associated with acute myocardial ischemia is the most common cause of sudden cardiac death, but its underlying mechanisms are incompletely understood. It is hypothesized that late Na+</sup>current (INa</sub>) contributes to arrhythmogenic activity in ischemic myocardium.Methods and Results:Langendorff-perfused rabbit hearts with regional ischemia in ventricles were optically mapped. Perfusion with ranolazine (10 μmol/L), a selective inhibitor of lateINa</sub>, significantly reduced excitation frequency and facilitated termination of VT/VF induced after occlusion of the left main coronary trunk. The activation pattern during ischemic VT/VF was characterized by breakthrough-type excitations (BEs) from multiple origins, predominantly in the ischemic border zone (BZ) and occasional short-lived rotors. Ranolazine perfusion significantly reduced the incidence of BEs in the BZ. Rotors tended to decrease with progression of ischemia and disappeared after ranolazine perfusion. During constant pacing, ranolazine attenuated ischemia-induced shortening of action potentials in the BZ without affecting conduction velocity, probably due toIKr</sub>inhibition. In intact hearts without coronary occlusion, ranolazine (10 μmol/L) terminated aconitine-induced VT by inhibiting focal arrhythmogenic activity in the injection site.</AbstractText>LateINa</sub>-mediated focal arrhythmogenic activity plays important roles in the maintenance of ischemic VT/VF in isolated rabbit hearts. Suppression of lateINa</sub>by ranolazine may be a promising therapeutic strategy to reduce arrhythmic death during the acute phase of myocardial infarction.</AbstractText> |
20,481 | The T<sub>peak</sub> - T<sub>end</sub> interval as an electrocardiographic risk marker of arrhythmic and mortality outcomes: A systematic review and meta-analysis. | The Tpeak</sub> - Tend</sub> interval (the interval from the peak to the end of the T wave), an electrocardiographic marker reflecting transmural dispersion of repolarization, has been used to predict ventricular tachycardia/fibrillation (VT/VF) and sudden cardiac death in different clinical settings.</AbstractText>This systematic review and meta-analysis evaluated the significance of the Tpeak</sub> - Tend</sub> interval in predicting arrhythmic and/or mortality end points.</AbstractText>PubMed, Embase, Cochrane Library, and CINAHL Plus databases were searched through November 30, 2016.</AbstractText>Of the 854 studies identified initially, 33 observational studies involving 155,856 patients were included in our meta-analysis. Tpeak</sub> - Tend</sub> interval prolongation (mean cutoff value 103.3 ± 17.4 ms) was a significant predictor of the arrhythmic or mortality outcomes (odds ratio [OR] 1.14; 95% confidence interval [CI] 1.11-1.17; P < .001). When different end points were analyzed, the ORs were as follows: VT/VF, 1.10 (95% CI 1.06-1.13; P < .0001); sudden cardiac death, 1.27 (95% CI 1.17-1.39; P < .0001); cardiovascular death, 1.40 (95% CI 1.19-1.64; P < .0001); and all-cause mortality, 4.56 (95% CI 0.62-33.68; P < .0001). Subgroup analysis for each disease revealed that the risk of VT/VF or death was highest for Brugada syndrome (OR 5.68; 95% CI 1.57-20.53; P < .01), followed by hypertension (OR 1.52; 95% CI 1.26-1.85; P < .0001), heart failure (OR 1.07; 95% CI 1.04-1.11; P < .0001), and ischemic heart disease (OR 1.06; 95% CI 1.02-1.10; P = 0.001).</AbstractText>The Tpeak</sub> - Tend</sub> interval is a useful risk stratification tool in different diseases and in the general population.</AbstractText>Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
20,482 | Cardiopulmonary Exercise Testing in Aortic Stenosis. | Patients with moderate to severe aortic stenosis (AVA <1.3 cm2</sup>) who were judged, by a referring cardiologist, as asymptomatic or equivocal symptomatic from the aortic stenosis were included in the study. Patients with left ventricular ejection fraction <50% were not included. Twenty-nine percent of the referred patients were judged asymptomatic and 71% equivocal symptomatic from their valve disease. The mean age was 72 years and 90% of the patients had an AVA-index <0.6 cm2</sup>/m2</sup>. By clinical evaluation in the outpatient clinic, 48% were judged as having functional limitation corresponding to NYHA≥II. The study participants had cardiopulmonary exercise testing (CPX) at inclusion, and, if relevant, pre- and nine months post-aortic valve replacement (AVR). CPX was feasible in 130 of 131 study participants recruited across 19 months. The coefficient of variability by test-retest was 5.4% and 4.6% for peak oxygen consumption (pVO2</sub>) and peak oxygen pulse (pO2pulse= pVO2</sub>/peak heart rate), respectively. The stroke volume generally increased with exercise, also in those with peak flow velocity across the aortic valve (Vmax) >5 m/s, >4 m/s, and <4 m/s but with high valvuloarterial impedance (Zva >5.5 mm Hg/(mL·m2</sup> )). This was found both when assessed by inert gas rebreathing and by the pO2pulse/hemoglobin index. Both resting and exercise stroke volume were lower for the latter group, with Vmax <4 m/s but high valvuloarterial impedance. A pVO2</sub> <83% of the predicted, which corresponds to the lower 95% percentile found in the healthy sedentary population, was predicted independently by lower stroke volume during exercise, lower heart rate during exercise, lower FEV1, and by higher ventilation/carbon dioxide exhaustion rate (VE/VCO2), but not by the severity of the aortic stenosis as determined by echocardiography. According to the CPX results, the patients were prospectively grouped into 3 groups, as follows: 1) normal pVO2</sub> (>83% of predicted) and pO2pulse (>95% of predicted); 2) subnormal pVO2</sub> or pO2pulse that according to CPX could be explained by causes other than hemodynamic compromise; 3) subnormal pVO2</sub> and pO2pulse. Groups 1 and 2 followed an initial conservative strategy, whereas Group 3 was referred for angiogram and Heart Team evaluation for AVR. The patients were followed for an average of 24 months and, in Groups 1 and 2, one patient (0.9%) suffered cardiac death and seven were hospitalized with heart failure (6.7%). The patient who died and another patient with heart failure had both previously, during the study, declined AVR. For Groups 1 and 2, the rate of the combined endpoint progression to cardiac death, hospitalization with heart failure, or AVR was 37.5%, which seems lower than what was reported in the literature by conventional assessment and strategy for younger asymptomatic patients with comparable echocardiographic severity of aortic stenosis. The endpoint progression to cardiac death, hospitalization with heart failure, or AVR with improvement in pVO2</sub> or in the Physical Component Score of the SF-36 health-related quality of life score was reached in 25.6% in Groups 1+2 and in 62.5% in Group 3 (p=0.003). A decreased pO2pulse, which expresses stroke volume at peak exercise, predicted this endpoint. In 73 operated patients without left ventricular dysfunction and no coronary stenosis, including 37 patients from the above-mentioned study, a CPX 9 months post-AVR showed that the pVO2</sub>, on average, was less than that predicted (mean 89% of the predicted ) and 35% of the patients had a subnormal pVO2</sub> (<83% of that predicted). A preoperative mean gradient <40 mm Hg across the aortic valve, the presence of atrial fibrillation, and a permanent pacemaker post-AVR all predicted a post-AVR pVO2</sub> <83% of that predicted. For the 37 patients with a pre-AVR CPX, a postoperative decrease >10% in the absolute pVO2</sub> was noted in 30% and an increase >10% in 24% of patients. A decrease >10% in pVO2</sub> was predicted by preoperative mean gradient <40 mm Hg and an increase in pVO2</sub> was predicted by preoperative AVAI <0.4 cm2</sup>/m2</sup> and preoperative pO2pulse <the median in the study population (<98% of that predicted).</AbstractText>In this group of patients, where clinical assessment is difficult and conventional exercise testing is regarded as less useful, CPX showed high feasibility and reproducibility. CPX therefore has potential as a useful tool for serial monitoring. In general, the stroke volume increased during exercise, including in patients with severe aortic stenosis or decreased resting stroke volume. CPX gives information on hemodynamics and the physiologic components that determine decreased pVO2</sub>. CPX seems useful to identify 1) patients with a low risk of cardiac death and low risk of progression to symptoms from the aortic stenosis, and 2) patients with hemodynamic compromise who improve in functional capacity after AVR. Patients with a preoperative mean gradient <40 mm Hg across the aortic valve, with the presence of atrial fibrillation or who have a permanent pacemaker, postoperatively seem to benefit less from AVR, whereas the benefit seems larger in those with more severe aortic stenosis and a decreased pO2pulse. These findings may be of importance for decisions and information of patients before AVR.</AbstractText>Articles published in the Danish Medical Journal are “open access”. This means that the articles are distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits any non-commercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.</CopyrightInformation> |
20,483 | Left ventricular longitudinal strain impairment predicts cardiovascular events in asymptomatic type 1 myotonic dystrophy. | Type 1 myotonic dystrophy (DM1) patients' prognosis is very poor. Up until now, only a few prognostic factors for cardiovascular events have been identified, and they are predictive of end-stage disease. The aim was to assess the prognostic value of global longitudinal strain (GLS) for cardiovascular events in asymptomatic DM1 patients.</AbstractText>DM1 patients were included between 2011 and 2015 and followed up until January 2016. Patients underwent a transthoracic echocardiography at inclusion. The primary endpoint was a composite of all-cause mortality, type 2 Mobitz 2 and type 3 atrioventricular block, symptomatic sino-atrial block, HV interval≥70ms at invasive electrophysiology exploration, left ventricular ejection fraction (LVEF) ≤45% and newly developed atrial fibrillation.</AbstractText>Forty-six patients (25 males, mean age 40years old) were included. The primary outcome was reached in 14 patients with a mean follow-up of 38months. GLS of patients who reached the primary endpoint was significantly impaired as compared to those who did not (-15.1 [-16.7; -12.7] vs. -18.2 [-19.2; -16.7] respectively; P=0.001). According to ROC curve analysis, probability of primary outcome occurrence was significantly greater in patients with GLS values≥-17.2% (P=0.001). On multivariate analysis, PR electrocardiogram interval and GLS remained significantly and independently associated with the primary endpoint [hazard ratio (HR) 1.03, 95% confidence interval (CI) 1.01-1.04, P=0.006 for PR interval; HR 1.4, 95% CI 1.1-1.7, P=0.002 for GLS] while LVEF alone was not.</AbstractText>Left ventricular GLS is a powerful marker to predict cardiovascular events in asymptomatic DM1 patients, independently of LVEF.</AbstractText>Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
20,484 | Atrial myofibroblast activation and connective tissue formation in a porcine model of atrial fibrillation and reduced left ventricular function. | Atrial fibrillation (AF) is associated with fibrosis that slows electrical conduction and causes perpetuation of the arrhythmia. The molecular characterization of AF pathophysiology may provide novel therapeutic options. This study was designed to elucidate profibrotic signaling and myofibroblast activation in a porcine model of atrial tachypacing-induced AF and reduced left ventricular function.</AbstractText>Ten domestic pigs were randomized to sinus rhythm (SR) or AF groups. Prior to AF induction and on day 14 the animals underwent echocardiographic examinations. Profibrotic pathways were analyzed in right atrial tissue obtained from AF animals compared to SR controls using histology, immunofluorescence microscopy, Western blot, and real-time PCR.</AbstractText>AF was associated with atrial dilation, increased atrial fibrosis, and enhanced expression of collagens I and V in right atrial tissue after 14days follow-up. The fraction of α-smooth muscle actin (SMA)-producing activated myofibroblasts was elevated in AF, whereas the abundance of vimentin-expressing inactive fibroblasts was not affected. Profibrotic signaling involved upregulation of TGF-β1</sub>, Smad2/3, and CTGF.</AbstractText>The transformation of atrial fibroblasts into myofibroblasts through activation of TGF-β1</sub> and CTGF emerged as potential cellular trigger of fibrogenesis. Prevention of fibroblast-to-myofibroblast switching may serve as target for remodeling-based antiarrhythmic AF therapy.</AbstractText>Copyright © 2017 Elsevier Inc. All rights reserved.</CopyrightInformation> |
20,485 | A systematic review of left ventricular cardio-endoscopic surgery. | Better visualisation, accurate resection and avoidance of ventriculotomy associated with use of endoscopic devices during intracardiac surgery has led to increasing interest in their use. The possibility of combining a cardio-endoscopic technique with either minimally invasive or totally endoscopic cardiac surgery provides an incentive for its further development. Several devices have been used, however their uptake has been limited due to uncertainty around their impact on patient outcomes. A systematic review of the literature identified 34 studies, incorporating 54 subjects undergoing treatment of left ventricular tumours, thrombus or hypertrophic myocardium using a cardio-endoscopic technique. There were no mortalities (0%; 0/47). In 12 studies, the follow-up period was longer than 30 days. There were no post-operative complications apart from one case of atrial fibrillation (2.2%; 1/46). Complete resection of left ventricular lesion was achieved in all cases (100%; 50/50). These successful results demonstrate that the cardio-endoscopic technique is a useful adjunct in resection of left ventricular tumours, thrombus and hypertrophic myocardium. This approach facilitates accurate resection of pathological tissue from left ventricle whilst avoiding exposure related valvular damage and adverse effects associated with ventriculotomy. Future research should focus on designing adequately powered comparative randomised trials focusing on major cardiac and cerebrovascular morbidity outcomes in both the short and long-term. In this way, we may have a more comprehensive picture of both the safety and efficacy of this technique and determine whether such devices could be safely adopted for routine use in minimal access or robotic intra-cardiac surgery. |
20,486 | [Impacts of early metoprolol intervention on connexin 43 and phosphorylated connexin 43 expression in rabbits with experimental myocardial infarction]. | <b>Objective:</b> To investigate the early intervention effects of metoprolol on connexin 43(Cx43) and phosphorylated Cx43 (p-Cx43) expression in rabbits with post myocardial infarction. <b>Methods:</b> A total of 24 adult male New Zealand white rabbits were divided into sham group (<i>n</i>=6), early treatment group(<i>n</i>=6), routine treatment group(<i>n</i>=6), and myocardial infarction group(<i>n</i>=6) with a randomized block design blocked by weight. Myocardial infarction was induced by left anterior descending coronary artery (LAD) ligation. Rabbits in sham group received similar surgical procedure without LAD ligation. Metoprolol (12.5 mg/kg dissolved in 2 ml distilled water) was applied to rabbits in early treatment group and routine treatment group per gavage immediately after recovery from anesthesia and at 24 hours after myocardial infarction, respectively, then treated daily for 40 days. Rabbits in sham group and myocardial infarction group received 2 ml distilled water per gavage daily for 40 days. Plasma lactate dehydrogenase (LDH) and creatine kinase (CK) level were detected by automatic biochemistry analyzer after 6 hours in all rabbits. Ventricular fibrillation threshold (VFT) was measured in vivo by bipolar pacing electrodes at 40 days. Cx43 and p-Cx43 distribution in ventricular tissue was detected by immunofluorescence analyses. Cx43 and p-Cx43 protein level in ventricular tissue was determined by Western blot. <b>Results:</b> (1) Plasma LDH ((851.7±85.9)U/L vs. (332.3±39.6)U/L, <i>P</i><0.01) and CK ((1 192.7±105.3)U/L vs. (462.3±65.6)U/L, <i>P</i><0.01) were significantly higher in myocardial infarction group than in sham group (both <i>P</i><0.01). (2) VFT was significantly lower in myocardial infarction group than that in sham group ((470.0±91.0) beats per minute vs. (683.3±60.9) beats per minute, <i>P</i><0.05), and VFT was significantly higher in early treatment group ((633.3±43.2) beats per minute) and routine treatment group ((645.0±30.8) beats per minute) than in the myocardial infarction group (both <i>P</i><0.05). (3) Immunofluorescence analyses showed that Cx43 was mainly localized in the intercalated disk, which was perpendicular to the cell long axis with linear arrangement, and less lateral distribution in sham group, early treatment group and routine treatment group, which was significantly different as the case in the myocardial infarction group. The expression of p-Cx43 in myocardial infarction group was less than in sham group, which was significantly upregulated in in early treatment group and routine treatment group when compared with myocardial infarction group, and expression of p-Cx43 was significantly higher in early treatment group than in routine treatment group. (4)The p-Cx43/Cx43 ratio of protein was significantly lower in myocardial infarction group than in sham group (0.165±0.011 vs. 0.363±0.046, <i>P</i><0.05), and significantly higher in early treatment group (0.720±0.063) and routine treatment group (0.364±0.030) than in myocardial infarction group (both <i>P</i><0.05), and this ratio was significantly higher in early treatment group than in routine treatment group (<i>P</i><0.05). <b>Conclusion:</b> Metoprolol treatment, especially the early metoprolol treatment (within 24 hours after LAD ligation), could significantly improve VFT by ameliorating the distribution and dephosphorylation of myocardial Cx43 in rabbits with experimental myocardial infarction.</Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Zhou</LastName><ForeName>M</ForeName><Initials>M</Initials><AffiliationInfo><Affiliation>Graduate School of Southern Medical University, Wuhan 430070, China.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Lu</LastName><ForeName>Q</ForeName><Initials>Q</Initials></Author><Author ValidYN="Y"><LastName>Jiang</LastName><ForeName>J Q</ForeName><Initials>JQ</Initials></Author><Author ValidYN="Y"><LastName>Chen</LastName><ForeName>Z N</ForeName><Initials>ZN</Initials></Author><Author ValidYN="Y"><LastName>Gong</LastName><ForeName>Z G</ForeName><Initials>ZG</Initials></Author><Author ValidYN="Y"><LastName>Li</LastName><ForeName>Z G</ForeName><Initials>ZG</Initials></Author><Author ValidYN="Y"><LastName>Fu</LastName><ForeName>W W</ForeName><Initials>WW</Initials></Author><Author ValidYN="Y"><LastName>Ding</LastName><ForeName>S F</ForeName><Initials>SF</Initials></Author></AuthorList><Language>chi</Language><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType></PublicationTypeList></Article><MedlineJournalInfo><Country>China</Country><MedlineTA>Zhonghua Xin Xue Guan Bing Za Zhi</MedlineTA><NlmUniqueID>7910682</NlmUniqueID><ISSNLinking>0253-3758</ISSNLinking></MedlineJournalInfo><ChemicalList><Chemical><RegistryNumber>0</RegistryNumber><NameOfSubstance UI="D018031">Connexin 43</NameOfSubstance></Chemical><Chemical><RegistryNumber>0</RegistryNumber><NameOfSubstance UI="D013565">Sympatholytics</NameOfSubstance></Chemical><Chemical><RegistryNumber>GEB06NHM23</RegistryNumber><NameOfSubstance UI="D008790">Metoprolol</NameOfSubstance></Chemical></ChemicalList><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D000818" MajorTopicYN="N">Animals</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D018031" MajorTopicYN="Y">Connexin 43</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D003331" MajorTopicYN="N">Coronary Vessels</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D006352" MajorTopicYN="N">Heart Ventricles</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008297" MajorTopicYN="N">Male</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008790" MajorTopicYN="N">Metoprolol</DescriptorName><QualifierName UI="Q000627" MajorTopicYN="Y">therapeutic use</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D009203" MajorTopicYN="Y">Myocardial Infarction</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D009206" MajorTopicYN="N">Myocardium</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D010766" MajorTopicYN="N">Phosphorylation</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D011817" MajorTopicYN="N">Rabbits</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D013565" MajorTopicYN="N">Sympatholytics</DescriptorName><QualifierName UI="Q000627" MajorTopicYN="Y">therapeutic use</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D014693" MajorTopicYN="N">Ventricular Fibrillation</DescriptorName></MeshHeading></MeshHeadingList><OtherAbstract Type="Publisher" Language="chi"><b>目的：</b> 探讨琥珀酸美托洛尔早期干预对陈旧性心肌梗死兔心脏组织缝隙连接蛋白43(Cx43)及其磷酸化(p-Cx43)水平的影响。 <b>方法：</b> 采用随机区组设计，以体重作为区组标志，将24只成年雄性新西兰大白兔分为假手术组(<i>n</i>＝6)、早期干预组(<i>n</i>＝6)、常规干预组(<i>n</i>＝6)和心肌梗死组(<i>n</i>＝6)。早期干预组、常规干预组和心肌梗死组通过结扎左前降支建立心肌梗死模型，假手术组不结扎冠状动脉，其余操作相同。早期干预组和常规干预组分别于麻醉清醒后和心肌梗死24 h后以琥珀酸美托洛尔(12.5 mg/kg，溶于2 ml蒸馏水中)灌胃，假手术组和心肌梗死组以等量蒸馏水灌胃，每天1次。术后6 h，以生物化学法检测血清心肌坏死标志物(血清乳酸脱氢酶和肌酸激酶)水平。术后40 d开胸暴露心脏，通过双极起搏电极测定心室颤动阈值。以免疫荧光法观察Cx43和p-Cx43在心室肌组织的分布情况。以Western blot检测心室肌组织Cx43及其磷酸化的蛋白表达水平。 <b>结果：</b> (1)心肌梗死组的血清乳酸脱氢酶[(851.7±85.9)U/L比(332.3±39.6)U/L，<i>P</i><0.01]和肌酸激酶[(1 192.7±105.3)U/L比(462.3±65.6)U/L，<i>P</i><0.01]水平均高于假手术组。(2)心肌梗死组的心室颤动阈值低于假手术组[(470.0±91.0)次/min比(683.3±60.9)次/min，<i>P</i><0.05]；早期干预组[(633.3±43.2)次/min]和常规干预组[(645.0±30.8)次/min]的心室颤动阈值均高于心肌梗死组(<i>P</i>均<0.05)。(3)免疫荧光法检测显示，假手术组、早期干预组和常规干预组的Cx43主要位于闰盘内，与细胞长轴垂直，呈线状排列，侧向分布的Cx43较少；心肌梗死组则相反。与假手术组比较，心肌梗死组p-Cx43表达较少；与心肌梗死组比较，早期干预组和常规干预组p-Cx43表达较多；早期干预组p-Cx43的表达多于常规干预组。(4)心肌梗死组的p-Cx43蛋白/Cx43蛋白低于假手术组(0.165±0.011比0.363±0.046，<i>P</i><0.05)；早期干预组(0.720±0.063)和常规干预组(0.364±0.030)的p-Cx43蛋白/Cx43蛋白均高于心肌梗死组(<i>P</i>均<0.05)；早期干预组的p-Cx43蛋白/Cx43蛋白高于常规干预组(<i>P</i><0.05)。 <b>结论：</b> 琥珀酸美托洛尔通过改善陈旧性心肌梗死兔心脏组织Cx43的空间分布和磷酸化水平，提高心室颤动阈值，而且心肌梗死后早期(24 h内)给药效果更明显。. |
20,487 | Isolated Right Ventricular Apical Trabecular Hypoplasia: A Case Report. | Right ventricular (RV) hypoplasia with isolated myocardial disease and complete absence of RV trabeculae is a rare congenital heart disease, the current treatment of which is ineffective. Here, a rare case is presented of a middle-aged female patient with RV hypoplasia complicated by tricuspid regurgitation, right atrial thrombus, and atrial fibrillation. The patient was treated with a one-and-a-half ventricular repair, and showed significant improvements in cardiac function and physical activity tolerance. The study results suggest that this surgical approach can significantly improve the prognosis of an adult patient with isolated RV hypoplasia. |
20,488 | Permanent nonselective His bundle pacing in an adult with L-transposition of the great arteries and complete AV block. | We report the placement of a permanent transvenous nonselective His bundle pacing lead in conjunction with a transvenous pacemaker/implantable cardioverter-defibrillator in an adult with Levo-Transposition of the Great Arteries (L-TGA) and a stenotic coronary sinus (CS) ostium, which would not accommodate a transvenous left ventricular (LV) pacing lead. Nonselective His bundle pacing provided a nearly identical ventricular activation pattern in this previously unpaced patient. Many L-TGA patients will have an eventual need for permanent pacing and, given the challenges of CS cannulation, His bundle pacing may represent a preferred modality rather than pure morphologic LV pacing or surgical systemic ventricular lead placement to achieve optimal electrical synchrony. |
20,489 | Right ventricular pacemaker lead position is associated with differences in long-term outcomes and complications. | Cardiac pacing from the right ventricular apex is associated with detrimental long-term effects and nonapical pacing locations may be associated with improved outcomes. There is little data regarding complications with nonapical lead positions. The aim of this study was to assess long-term outcomes and lead-related complications associated with differing ventricular lead tip position.</AbstractText>All adult patients who underwent dual-chamber pacemaker implantation from 2004 to 2014 were included if they had postprocedure chest radiographs amenable to lead position determination. Long-term outcomes and lead-related complication rates were recorded. These were compared at 5 years between: (1) apical and septal leads, (2) apical and nonseptal nonapical (NSNA), and (3) apical and septal with >40% ventricular pacing. We retrospectively evaluated 3,450 patients, which included 238 with a septal position and 733 with NSNA lead positions. Septal lead position was associated with a lower mortality compared to apical leads (24% vs. 31%, P = 0.02). In patients with greater than 40% pacing, septal leads were associated with significantly higher rates of incident atrial fibrillation compared to apical leads (49% vs. 34%, P = 0.04). NSNA positions were associated with a significantly higher rate of lead dislodgement (4% vs. 2%, P = 0.005) and need for revision (8% vs. 5%, P = 0.005).</AbstractText>Septal pacemaker lead position is associated with a lower mortality compared to apically placed leads, but a higher incidence of atrial fibrillation with higher percentage ventricular pacing. NSNA lead locations are associated with more complications and should be avoided.</AbstractText>© 2017 Wiley Periodicals, Inc.</CopyrightInformation> |
20,490 | Baroreceptor stimulation in a patient with preexisting subcutaneous implantable cardioverter defibrillator. | Many patients with severe heart failure (HF) have an indication for baroreflex activation therapy (BAT) and an implantable cardioverter-defibrillator (ICD). Concerns about device-device interactions were addressed in a study with small sample size that concluded combined BAT and ICD therapy is safe. There are no published data, however, concerning device-device interactions between BAT and a subcutaneous ICD (S-ICD). Since BAT frequently interferes with surface electrocardiogram recordings, there are doubts about compatibility of BAT and S-ICD devices.</AbstractText>A 54-year-old male patient with dilated cardiomyopathy and severely reduced left ventricular ejection fraction received an S-ICD after recurrent systemic infections due to a diabetic foot syndrome, ultimately associated with infective endocarditis. Since medical HF therapy could not be further optimized and the patient presented with persistent cardiac decompensations, he was evaluated for BAT. Preoperatively, the barostim was epicutaneously placed on the patient's thorax with conductive gel in order to evaluate a possible interference with the S-ICD. Positioning of the barostim in loco typico did not affect the S-ICD's sensing in any vector. Only positioning of the carotis sinus lead directly upon the S-ICD lead, which is beyond clinical relevance, lead to missensing. Subsequently, BAT was implanted with successful perioperative testing of the S-ICD: there was accurate detection of ventricular fibrillation and immediate termination via first shock delivery under maximum barostim output.</AbstractText>To our knowledge, there are no other reports in which a barostim was safely implanted in a patient with a preexisting S-ICD. Until data with large patient numbers are available, individual perioperative testing is highly recommended.</AbstractText>© 2017 Wiley Periodicals, Inc.</CopyrightInformation> |
20,491 | Stricter criteria for left bundle branch block diagnosis do not improve response to CRT. | Cardiac resynchronization therapy (CRT) has proved to be effective in patients with heart failure and left bundle branch block (LBBB). Recently, new electrocardiography criteria have been proposed for the diagnosis of LBBB. These criteria are stricter than the current American Heart Association (AHA) criteria. We assessed the rate of echocardiographic response to CRT in patients with traditional LBBB versus patients who met the new criteria (strict LBBB).</AbstractText>Consecutive patients undergoing CRT were enrolled in the CRT MORE registry. Patients with no-LBBB QRS morphology according to AHA criteria, atrial fibrillation, right bundle branch block, and right ventricular pacing were excluded. Strict LBBB was defined as: QRS ≥ 140 ms for men and ≥130 ms for women, QS or rS in V1-V2, mid-QRS notching or slurring in ≥2 contiguous leads. Patients showing a relative decrease of ≥15% in left ventricular end-systolic volume (LVESV) at 12 months were defined as responders.</AbstractText>Among 335 patients with LBBB, 131 (39%) had strict LBBB. Patients with and without strict LBBB showed comparable baseline characteristics, except for QRS duration (166 ± 20 ms vs 152 ± 25 ms, P < 0.001). On 12-month evaluation, 205 patients (61%) were responders; 85 of 131 (65%) had strict LBBB and 120 of 204 (59%) had traditional LBBB (P = 0.267). On multivariate analysis, a history of atrial fibrillation, larger LVESV, and the presence of mid-QRS notching in ≥1 lead (odds ratio 2.099; 95% confidence interval 1.061-4.152, P = 0.033) were independently associated with echocardiographic response.</AbstractText>Stricter definition of LBBB did not improve response to CRT in comparison to the current AHA definition.</AbstractText>© 2017 Wiley Periodicals, Inc.</CopyrightInformation> |
20,492 | "Real life" longevity of implantable cardioverter-defibrillator devices. | Manufacturers of implantable cardioverter-defibrillators (ICDs) promise a 5- to 9-year projected longevity; however, real-life data indicate otherwise. The aim of the present study was to assess ICD longevity among 685 consecutive patients over the last 20 years.</AbstractText>Real-life longevity of ICDs may differ from that stated by the manufacturers.</AbstractText>The study included 601 men and 84 women (mean age, 63.1 ± 13.3 years). The underlying disease was coronary (n = 396) or valvular (n = 15) disease, cardiomyopathy (n = 220), or electrical disease (n = 54). The mean ejection fraction was 35%. Devices were implanted for secondary (n = 562) or primary (n = 123) prevention. Single- (n = 292) or dual-chamber (n = 269) or cardiac resynchronization therapy (CRT) devices (n = 124) were implanted in the abdomen (n = 17) or chest (n = 668).</AbstractText>Over 20 years, ICD pulse generator replacements were performed in 238 patients (209 men; age 63.7 ± 13.9 years; ejection fraction, 37.7% ± 14.0%) who had an ICD for secondary (n = 210) or primary (n = 28) prevention. The mean ICD longevity was 58.3 ± 18.7 months. In 20 (8.4%) patients, devices exhibited premature battery depletion within 36 months. Most (94%) patients had none, minor, or modest use of ICD therapy. Longevity was longest for single-chamber devices and shortest for CRT devices. Latest-generation devices replaced over the second decade lasted longer compared with devices replaced during the first decade. When analyzed by manufacturer, Medtronic devices appeared to have longer longevity by 13 to 18 months.</AbstractText>ICDs continue to have limited longevity of 4.9 ± 1.6 years, and 8% demonstrate premature battery depletion by 3 years. CRT devices have the shortest longevity (mean, 3.8 years) by 13 to 17 months, compared with other ICD devices. These findings have important implications, particularly in view of the high expense involved with this type of electrical therapy.</AbstractText>© 2017 Wiley Periodicals, Inc.</CopyrightInformation> |
20,493 | The inward rectifier current inhibitor PA-6 terminates atrial fibrillation and does not cause ventricular arrhythmias in goat and dog models. | The density of the inward rectifier current (IK1</sub> ) increases in atrial fibrillation (AF), shortening effective refractory period and thus promoting atrial re-entry. The synthetic compound pentamidine analogue 6 (PA-6) is a selective and potent IK1</sub> inhibitor. We tested PA-6 for anti-AF efficacy and potential proarrhythmia, using established models in large animals.</AbstractText>PA-6 was applied i.v. in anaesthetized goats with rapid pacing-induced AF and anaesthetized dogs with chronic atrio-ventricular (AV) block. Electrophysiological and pharmacological parameters were determined.</AbstractText>PA-6 (2.5 mg·kg-1</sup> ·10 min-1</sup> ) induced cardioversion to sinus rhythm (SR) in 5/6 goats and prolonged AF cycle length. AF complexity decreased significantly before cardioversion. PA-6 accumulated in cardiac tissue with ratios between skeletal muscle : atrial muscle : ventricular muscle of approximately 1:8:21. In SR dogs, PA-6 peak plasma levels 10 min post infusion were 5.5 ± 0.9 μM, PA-6 did not induce significant prolongation of QTc and did not affect heart rate, PQ or QRS duration. In dogs with chronic AV block, PA-6 did not affect QRS but lengthened QTc during the experiment, but not chronically. PA-6 did not induce TdP arrhythmias in nine animals (0/9) in contrast to dofetilide (5/9). PA-6 (200 nM) inhibited IK1</sub> , but not IK,ACh</sub> , in human isolated atrial cardiomyocytes.</AbstractText>PA-6 restored SR in goats with persistent AF and, in dogs with chronic AV block, prolonged QT intervals, without inducing TdP arrhythmias. Our results demonstrate cardiac safety and good anti-AF properties for PA-6.</AbstractText>© 2017 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.</CopyrightInformation> |
20,494 | The IK1/Kir2.1 channel agonist zacopride prevents and cures acute ischemic arrhythmias in the rat. | Arrhythmogenesis in acute myocardial infarction (MI) is associated with depolarization of resting membraine potential (RMP) and decrease of inward rectifier potassium current (IK1) in cardiomyocytes. However, clinical anti-arrhythmic agents that primarily act on RMP by enhancing the IK1 channel are not currently available. We hypothesized that zacopride, a selective and moderate agonist of the IK1/Kir2.1 channels, prevents and cures acute ischemic arrhythmias. To test this viewpoint, adult Sprague-Dawley (SD) rats were subjected to MI by ligating the left main coronary artery. The antiarrhythmic effects of zacopride (i.v. infusion) were observed in the settings of pre-treatment (zacopride given 3 min prior to coronary occlusion), post-treatment (zacopride given 3 min after coronary occlusion) and therapeutic treatment (zacopride given 30 s after the onset of the first sustained ventricular tachycardia (VT)/ventricular fibrillation (VF) post MI). In all the three treatment modes, zacopride (15 μg/kg) inhibited MI-induced ventricular tachyarrhythmias, as shown by significant decreases in the premature ventricular contraction (PVC) and the duration and incidence of VT or VF. In Langendorff perfused rat hearts, the antiarrhythmic effect of 1 μmol/L zacopride were reversed by 1 μmol/L BaCl2, a blocker of IK1 channel. Patch clamp results in freshly isolated rat ventricular myocytes indicated that zacopride activated the IK1 channel and thereby reversed hypoxia-induced RMP depolarization and action potential duration (APD) prolongation. In addition, zacopride (1 μmol/L) suppressed hypoxia- or isoproterenol- induced delayed afterdepolarizations (DADs). In Kir2.x transfected Chinese hamster ovary (CHO) cells, zacopride activated the Kir2.1 homomeric channel but not the Kir2.2 or Kir2.3 channels. These results support our hypothesis that moderately enhancing IK1/Kir2.1 currents as by zacopride rescues ischemia- and hypoxia- induced RMP depolarization, and thereby prevents and cures acute ischemic arrhythmias. This study brings a new viewpoint to antiarrhythmic theories and provides a promising target for the treatment of acute ischemic arrhythmias. |
20,495 | Improvement of left ventricular diastolic function and left heart morphology in young women with morbid obesity six months after bariatric surgery. | Obesity contributes to left ventricular (LV) diastolic dysfunction (LVDD) and may lead to diastolic heart failure. Weight loss (WL) after bariatric surgery (BS) may influence LV morphology and function. Using echocardiography, this study assessed the effect of WL on LV diastolic function (LVDF) and LV and left atrium (LA) morphology 6 months after BS in young women with morbid obesity.</AbstractText>Echocardiography was performed in 60 women with body mass index ≥ 40 kg/m², aged 37.1 ± ± 9.6 years prior to and 6 months after BS. In 38 patients, well-controlled arterial hypertension was present. Heart failure, coronary artery disease, atrial fibrillation and mitral stenosis were exclusion criteria. Parameters of LV and LA morphology were obtained. To evaluate LVDF, mitral peak early (E) and atrial (A) velocities, E-deceleration time (DcT), pulmonary vein S, D and A reversal velocities were measured. Peak early diastolic mitral annular velocities (E') and E/E' were assessed.</AbstractText>Mean WL post BS was 35.7 kg (27%). A postoperative decrease in LV wall thickness, LV mass (mean 183.7 to 171.5 g, p = 0.001) and LA parameters (area, volume) were observed. LVDD was diagnosed in 3 patients prior to and in 2 of them subsequent to the procedure. An improvement in LVDF Doppler indices were noted: increased E/A, D and E' lateral, and decreased S/D and lateral E/E'. None of the patients showed increased LV filling pressure. No significant correlations between hypertension and echo-parameters were demonstrated.</AbstractText>Six months after BS weight loss resulted in the improvement of LVDF and left heart morphology in morbidly obese women. (Cardiol J 2018; 25, 1: 97-105).</AbstractText> |
20,496 | Hypertension and cardiac arrhythmias: executive summary of a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE). | Hypertension (HTN) is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease (CAD), stroke, peripheral artery disease and chronic renal failure. Hypertensive heart disease can manifest as many types of cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both supraventricular and ventricular arrhythmias may occur in HTN patients, especially in those with left ventricular hypertrophy (LVH), CAD, or HF. In addition, high doses of thiazide diuretics commonly used to treat HTN, may result in electrolyte abnormalities (e.g. hypokalaemia, hypomagnesaemia), contributing further to arrhythmias, while effective blood pressure control may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between HTN and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit of comprehensively reviewing the available evidence and publishing a joint consensus document on HTN and cardiac arrhythmias, and providing up-to-date consensus recommendations for use in clinical practice. The ultimate judgment on the care of a specific patient must be made by the healthcare provider and the patient in light of all individual factors presented. This is an executive summary of the full document co-published by EHRA in EP-Europace. |
20,497 | Progressive increase of the Tpeak-Tend interval is associated with ischaemia-induced ventricular fibrillation in a porcine myocardial infarction model. | Repolarization indices of ECG have been widely assessed as predictors of ventricular arrhythmias. However, little is known of the dynamic changes of these parameters during continuous monitoring in acute ischaemic episodes. The objective of the study was to evaluate repolarization-related predictors of ventricular fibrillation (VF) during progression of experimental myocardial infarction.</AbstractText>Myocardial infarction was induced in 27 pigs by 40-min balloon inflation in the left anterior descending coronary artery, and 12-lead ECG was continuously recorded. Rate-corrected durations of the total Tpeak-Tend intervals measured from the earliest T-wave peak to the latest T-wave end in any lead were determined at baseline and at minute 1, 2, 5, and then every 5th minute of occlusion. There were 7 early (1-3 min) and 10 delayed (15-30 min) VFs in 16 pigs. Baseline Tpeak-Tend did not differ between animals with and without VF. Tpeak-Tend interval rapidly increased immediately after balloon inflation and was greater in VF-susceptible animals at 2-15 min compared with the animals that never developed VF (P < 0.05). Tpeak-Tend was tested as a predictor of delayed VFs. Median Tpeak-Tend at 10th min of occlusion was higher in delayed VF group (n = 10) than in animals without VF (n = 11): 138 [IQR 121-148] ms vs. 111 [IQR 106-127] ms, P = 0.02. Tpeak-Tend  ≥123 ms (10th min) predicted delayed VF episodes with HR = 4.5 95% CI 1.1-17.8, P = 0.031.</AbstractText>Tpeak-Tend prolongation during ischaemia progression predicts VF in the experimental porcine myocardial infarction model and warrants further testing in clinical settings of acute coronary syndromes.</AbstractText> |
20,498 | Systemic Inflammation and Arrhythmogenesis: A Review of Mechanistic and Clinical Perspectives. | In the recent decades, systemic inflammation, as a clinical phenomenon, has been the focus of extensive research particularly with regard to its potential association with a variety of cardiovascular diseases including atherogenesis and acute coronary syndromes. Within this context, there also exists a potential link between systemic inflammation and cardiac arrhythmogenesis in various aspects. Accordingly, systemic inflammation response as measured with inflammation markers (cytokines, etc) has been investigated in the setting of well-known cardiac arrhythmias including atrial fibrillation and ventricular tachycardia. Based on current literature, clinical utility of these markers might potentially yield important prognostic implications in the setting of certain arrhythmogenic conditions. On the other hand, there exists limited data regarding therapeutic implications including clinical benefit of primary anti-inflammatory agents (corticosteroids, colchicine, etc) in the setting of arrhythmia management. The present review primarily aims to discuss potential triggers and fundamental mechanisms of inflammation-related arrhythmias along with a particular emphasis on clinical implications of systemic inflammation in the setting of cardiac arrhythmogenesis. |
20,499 | Actual management and prognosis of severe isolated tricuspid regurgitation associated with atrial fibrillation without structural heart disease. | Patients with atrial fibrillation (AF) without structural heart diseases can show severe tricuspid regurgitation (TR), especially among aged people. The aim of this study was to clarify the actual management, prognosis, and prognostic factors for severe isolated TR associated with AF without structural heart diseases.</AbstractText>We retrospectively investigated actual management in 178 consecutive patients with severe isolated TR associated with AF between 1999 and 2011 in our institution. Prognosis and its predictors were also investigated in 115 patients (68 persistent TR and 47 transient TR) who were followed-up for >1year. During the follow-up period (mean: 5.9years), event free rate from death due to right-sided heart failure (RHF) was 97% at 5years. Persistent TR was associated with higher risk of hospitalization due to RHF than transient TR (log-rank P=0.048) and death due to RHF were all seen in patients with persistent TR who experienced hospitalization due to RHF. Among patients with persistent TR, right ventricular outflow tract dimension >35.3mm, right atrial area >40.3cm2</sup>, and tenting height >2.1mm were associated with higher risk of hospitalization due to RHF (adjusted hazard ratio: 3.32, 3.83, and 2.89, respectively; P=0.003, 0.002, and 0.009, respectively).</AbstractText>The prognosis of severe isolated TR associated with AF was good with a focus on cardiac death. However, the incidence of cardiac death increased among patients who experienced hospitalization due to RHF. Larger right ventricular outflow tract dimension, right atrial area and tenting height were predictors of hospitalization due to RHF.</AbstractText>Copyright © 2017 Elsevier B.V. All rights reserved.</CopyrightInformation> |
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