Serial secretoneurin measurement and risk of ventricular arrhythmias and death in patients with left ventricular systolic dysfunction.

Background: Secretoneurin, a member of the granin protein family, is associated with the risk of mortality in patients with acute and chronic heart failure. Secretoneurin may play an important role in cardiomyocyte calcium handling, suggesting that it may influence cardiac arrhythmia risk. We hypothesized that baseline and serial measurements of circulating secretoneurin are associated with the risk of incident ventricular tachyarrhythmias (VA) and death, and that serial measurement would provide prognostic information beyond baseline values.

Dual vs Single Cardioversion of Atrial Fibrillation in Patients With Obesity: A Randomized Clinical Trial.

Importance: Atrial fibrillation and obesity are common, and both are increasing in prevalence. Obesity is associated with failure of cardioversion of atrial fibrillation using a standard single set of defibrillator pads, even at high output.

Objective: To compare the efficacy and safety of dual direct-current cardioversion (DCCV) using 2 sets of pads, with each pair simultaneously delivering 200 J, with traditional single 200-J DCCV using 1 set of pads in patients with obesity and atrial fibrillation.

Risk of ventricular arrhythmias following implantable cardioverter-defibrillator generator change in patients with recovered ejection fraction: Implications for shared decision-making.

Introduction: Guidelines indicate primary-prevention implantable cardioverter-defibrillators (ICDs) for most patients with left ventricular ejection fraction (LVEF) ≤ 35%. Some patients' LVEFs improve during the life of their first ICD. In patients with recovered LVEF who never received appropriate ICD therapy, the utility of generator replacement upon battery depletion remains unclear.

Sacubitril/valsartan: An antiarrhythmic drug?

Introduction: Heart failure (HF) is a major cause of morbidity and mortality, with nearly half of all HF-related deaths resulting from sudden cardiac death (SCD), most often from an arrhythmic event. The pathophysiologic changes that occur in response to the hemodynamic stress of HF may lead to increased arrhythmogenesis. Theoretically, medications that block these arrhythmogenic substrates would decrease the risk of SCD.

The role of atrial fibrillation catheter ablation in patients with heart failure.

Atrial Fibrillation (AF) and heart failure (HF) with reduced ejection fraction (HFrEF) frequently coexist, resulting in significant morbidity and mortality. Therapeutic options for patients with AF and HFrEF are limited due to few antiarrhythmic drug (AAD) choices and historically equivocal effects of procedural interventions on mortality. However, recent randomized trials examining catheter ablation (CA) in AF patients with HFrEF have shown a beneficial effect on arrhythmic burden and HF symptoms, as well as an improvement in mortality.

Epidemiology, evaluation, and management of conduction disturbances after transcatheter aortic valve replacement.

Aortic stenosis is the most common valvulopathy requiring replacement by means of the surgical or transcatheter approach. Transcatheter aortic valve replacement (TAVR) has quickly become a viable and often preferred treatment strategy compared to surgical aortic valve replacement. However, transcatheter heart valve system deployment not infrequently injures the specialized electrical system of the heart, leading to new conduction disorders including high-grade atrioventricular block and complete heart block (CHB) necessitating permanent pacemaker implantation (PPI), which may lead to deleterious effects on cardiac function and patient outcomes.

Utility of serial measurement of biomarkers of cardiovascular stress and inflammation in systolic dysfunction.

Aims: Evidence links markers of systemic inflammation and heart failure (HF) with ventricular arrhythmias (VA) and/or death. Biomarker levels, and the risk they indicate, may vary over time. We evaluated the utility of serial laboratory measurements of inflammatory biomarkers and HF, using time-dependent analysis.

Positron emission tomography absolute stress myocardial blood flow for risk stratification in nonischemic cardiomyopathy.

Introduction: Sudden cardiac death is a substantial cause of mortality in patients with cardiomyopathy, but evidence supporting implantable cardioverter-defibrillator (ICD) implantation is less robust in nonischemic cardiomyopathy (NICM) than in ischemic cardiomyopathy. Improved risk stratification is needed. We assessed whether absolute quantification of stress myocardial blood flow (sMBF) measured by positron emission tomography (PET) predicts ventricular arrhythmias (VA) and/or death in patients with NICM.

Class 1C antiarrhythmic drugs in atrial fibrillation and coronary artery disease.

Background: Class 1C antiarrhythmic drugs (AADs) are effective first-line agents for atrial fibrillation (AF) treatment. However, these agents commonly are avoided in patients with known coronary artery disease (CAD), due to known increased risk in the postmyocardial infarction population. Whether 1C AADs are safe in patients with CAD but without clinical ischemia or infarct is unknown.

Optimal method of measuring the T-peak to T-end interval for risk stratification in primary prevention.

Aims: Several published investigations demonstrated that a longer T-peak to T-end interval (Tpe) implies increased risk for ventricular tachyarrhythmia (VT/VF) and mortality. Tpe has been measured using diverse methods. We aimed to determine the optimal Tpe measurement method for screening purposes.

Natural History and Implantable Cardioverter-Defibrillator Implantation After Revascularization for Stable Coronary Artery Disease With Depressed Ejection Fraction.

Background: Following revascularization, most payors require 3 months of medical therapy, followed by left ventricular ejection fraction (LVEF) reassessment, before implantable cardioverter-defibrillator (ICD) implantation possibly contributing to incomplete follow-up and suboptimal utilization of ICD therapy. The natural history of these patients, and their fate regarding ICD implantation, is unknown.

Hypothesis: We hypothesized that a waiting period after revascularization for stable CAD results in missed opportunities to provide care with regard to ICD implantation.

T-peak to T-end interval for prediction of ventricular tachyarrhythmia and mortality in a primary prevention population with systolic cardiomyopathy.

Background: The electrocardiographic T-wave peak to T-wave end interval (Tpe) correlates with dispersion of ventricular repolarization (DVR). Increased DVR increases propensity toward electrical reentry that can cause ventricular tachyarrhythmia. The baseline rate-corrected Tpe (Tpec) has been shown to predict ventricular tachyarrhythmia and death in multiple patient populations but not among cardiomyopathic patients undergoing insertion of an implantable cardioverter-defibrillator (ICD) for primary prevention.

Endocardial unipolar voltage mapping to identify epicardial substrate in arrhythmogenic right ventricular cardiomyopathy/dysplasia.

Background: The risk and success of epicardial substrate ablation for ventricular tachycardia (VT) support the value of techniques identifying the epicardial substrate with endocardial mapping.

Objective: The purpose of this study was to test the hypothesis that endocardial unipolar voltage mapping in patients with right ventricular (RV) VT and preserved endocardial bipolar voltage abnormalities might identify the extent of epicardial bipolar voltage abnormality.

Methods: Using a cutoff of < 5.

Outcome of percutaneous coronary intervention in unstable angina pectoris versus stable angina pectoris in two different time periods.

Percutaneous coronary intervention (PCI) for unstable angina pectoris (UAP) has traditionally been associated with a higher risk of ischemic complications than that for stable angina pectoris (SAP). However, PCI procedures have evolved, so this study was designed to determine whether PCI for UAP is still associated with less favorable outcomes. In-hospital and 1-year outcomes in Dynamic Registry patients who presented for PCI with UAP (n = 2,994) or SAP (n = 1,457) between 1997 and 2002 were compared.

Proper management of pericardial tamponade as a late complication of implantable cardiac device placement.

Cardiac tamponade as a late complication of device placement is exceedingly rare, with only several case reports previously published. We sought to characterize our institution's experience with cardiac tamponade occurring >30 days after permanent pacemaker or implantable cardioverter-defibrillator placement. From January 2000 to June 2003, 2,535 patients received an implantable cardiac device at our institution.

An integrated approach to measuring tumor oxygen status using human melanoma xenografts as a model.

Tumor oxygen status is a reliable prognostic marker that impacts malignant progression and outcome of tumor therapy. However, tumor oxygenation is heterogeneous and cannot be sufficiently described by a single parameter. It is influenced by several factors including microvessel density (MVD), blood flow (BF), blood volume (BV), blood oxygen saturation, tissue pO(2), oxygen consumption rate, and hypoxic fraction.