Implantable cardioverter defibrillators: do women fare worse than men? Gender comparison in the INTRINSIC RV trial.

Introduction: Due to limited enrollment of women in previous trials, there is a paucity of data comparing outcome and arrhythmic events in men versus women with implantable cardioverter defibrillators (ICDs).

Methods And Results: We analyzed outcome of patients in the INTRINSIC RV (Inhibition of Unnecessary RV Pacing with AV Search Hysteresis in ICDs) trial based on gender. Women comprised 19% (293/1530) of the INTRINSIC RV population.

Correlation of noninvasive electrocardiography with invasive electrophysiology in syncope of unknown origin: implications from a large syncope database.

Background: The evaluation of syncope can be expensive, unfocussed, and unrevealing yet, failure to diagnose an arrhythmic cause of syncope is a major problem. We investigate the utility of noninvasive electrocardiographic evaluation (12-lead ECG and 24-hour ambulatory electrocardiographic recordings) to predict electrophysiology study results in patients with undiagnosed syncope.

Methods: We evaluated 421 patients with undiagnosed syncope who had an electrocardiogram (ECG), an electrophysiology study, and 24-hour ambulatory monitoring.

Influence of left ventricular lead location on outcomes in the COMPANION study.

Introduction: There are no randomized controlled trial data that evaluate mortality and hospitalization rates in cardiac resynchronization therapy (CRT) recipients based on left ventricular (LV) lead location. We analyzed the event-driven outcomes of mortality and hospitalization as well as functional outcomes including Functional Class, Quality-of-Life, and 6-minute walk distance in 1,520 patients enrolled in the COMPANION study of CRT versus optimal medical therapy.

Methods And Results: Over a mean follow-up after implantation of 16.

Advances in the management of atrial fibrillation in congestive heart failure.

Atrial fibrillation, a common problem in patients with heart failure, is associated with increased mortality and morbidity. Pharmacological as well as invasive management and the endpoints of such management are complex. Recent randomized trials indicate that a rate-control strategy, along with anticoagulation treatment with warfarin, when appropriate, has a similar outcome in terms of mortality and morbidity as rhythm control, and could, therefore, be considered as the primary management strategy for atrial fibrillation in patients with heart failure.

Newly detected atrial fibrillation in patients with an implantable cardioverter-defibrillator is a strong risk marker of increased mortality.

Background: Atrial fibrillation (AF) has been associated with higher rates of all-cause mortality in patients with heart failure (HF). The risk of newly detected AF in patients receiving implantable cardioverter-defibrillator (ICD) therapy is unknown.

Methods: Newly detected AF was evaluated in all patients enrolled in the Inhibition of Unnecessary RV Pacing with AV Search Hysteresis in ICDs (INTRINSIC RV) study.

Differential pharmacological effects of antimuscarinic drugs on heart rate: a randomized, placebo-controlled, double-blind, crossover study with tolterodine and darifenacin in healthy participants > or = 50 years.

Antimuscarinics, used commonly to treat overactive bladder, may differ in their potential to increase heart rate via effects on cardiac muscarinic M2 receptors. This prospective, 3-way crossover, randomized, double-blind study assessed the heart rate effects of 7 days' exposure to a nonselective M2/M3 receptor blocker (tolterodine; 4 mg/d), a highly selective M3 receptor blocker (darifenacin; 15 mg/d), and placebo in 162 healthy participants > or = 50 years. Heart rate was measured by 24-hour Holter monitoring.

Antiarrhythmic effects of statins in heart failure.

In vitro heart failure models indicate that statins may be antiarrhythmic, but the mechanisms by which statins are antiarrhythmic are not completely understood. Several retrospective and post hoc analysis studies also indicate that statins can be antiarrhythmic in heart failure populations, but this was not confirmed by a recent large prospective randomized controlled clinical trial. Ongoing and future clinical trials will likely resolve the discrepancies between studies and further the understanding of how pleiotropic properties of statins can be antiarrhythmic in patients who have heart failure.

Syncope predicts the outcome of cardiomyopathy patients: analysis of the SCD-HeFT study.

Objectives: The outcome of congestive heart failure (CHF) patients with syncope is understood incompletely.

Background: We analyzed data from patients enrolled in the SCD-HeFT (Sudden Cardiac Death Heart Failure Trial) to determine whether syncope predicted outcomes in patients with CHF.

Methods: We compared outcomes (and associated clinical characteristics) in patients with and without syncope enrolled in SCD-HeFT.

High defibrillation energy requirements are encountered rarely with modern dual-chamber implantable cardioverter-defibrillator systems.

Aims: Defibrillation conversion testing to assure a 10 J safety margin is a standard practice during implantable cardioverter-defibrillator (ICD) implantation. Little data are available on the number of patients who do not have a 10 J margin initially and therefore require system revisions, further testing, or a higher energy output device.

Methods And Results: The INTRINSIC RV study enrolled 1530 new ICD recipients who were not in permanent atrial fibrillation who received a VITALITY AVT (Guidant, St Paul, MN, USA) standard energy (31 J maximum) ICD and underwent defibrillation conversion testing at the time of implantation from 108 centres.

Sport and arrhythmias: summary of an international symposium.

This article is the report of an International Symposium endorsed by the European Society of Cardiology, held within the Venice Arrhythmias 2007: 10 International Workshop on Cardiac Arrhythmias (Venice, October 2007). The topics of the Symposium are the following: how to stratify the risk of sudden death in athletes; the role of different diagnostic examinations in the risk stratification of sudden death in athletes; controversies on arrhythmias and sport; and exercise prescription in patients with arrhythmias.

Treating patients with overactive bladder syndrome with antimuscarinics: heart rate considerations.

In this excellent mini-review, the authors present an extensive and relevant paper on the effect of antimuscarinic agents on the heart. This is without doubt the most detailed and the most reader-friendly paper on this subject, and I am sure that it will help urologists to assist in further educating their patients when prescribing these compounds.

A practical guide for clinicians who treat patients with amiodarone: 2007.

Amiodarone is commonly used to treat supraventricular and ventricular arrhythmias in various inpatient and outpatient settings. Over- and under-use of amiodarone is common, and data regarding patterns of use are sparse and largely anecdotal. Because of adverse drug reactions, proper use is essential to deriving optimal benefits from the drug with the least risk.

Sex differences in the relationship between amiodarone use and the need for permanent pacing in patients with atrial fibrillation.

Background: Amiodarone use was associated with an increased need for pacemaker insertion in a retrospective study of patients with atrial fibrillation (AF) and prior myocardial infarction. The aims of this study were to determine prospectively whether amiodarone increases the need for pacemakers in a general population of patients with AF and whether this effect is modified by sex.

Methods: The study included 1005 patients with new-onset AF who were enrolled in the Fibrillation Registry Assessing Costs, Therapies, Adverse events, and Lifestyle (FRACTAL).

Eliminating right ventricular pacing may not be best for patients requiring implantable cardioverter-defibrillators.

Background: Excessive right ventricular (RV) pacing has been associated with adverse clinical outcomes in patients receiving pacemakers or implantable cardioverter-defibrillators (ICDs). It remains uncertain how much RV pacing is clinically deleterious.

Objective: This retrospective analysis assessed the relationship between the amount of RV pacing and the composite of all-cause mortality and heart failure hospitalization in all patients programmed DDDR in the Inhibition of Unnecessary RV Pacing with AV Search Hysteresis in ICDs (INTRINSIC RV) study.

Where patients with mild to moderate heart failure die: results from the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT).

Background: Common locations of death in patients with congestive heart failure (CHF) are unknown. In the SCD-HeFT, mortality of patients with CHF was assessed after randomization to an implantable cardioverter/defibrillator (ICD), amiodarone, or placebo. The aim of this study was to evaluate the location of deaths in SCD-HeFT.

Statin use was associated with reduced mortality in both ischemic and nonischemic cardiomyopathy and in patients with implantable defibrillators: mortality data and mechanistic insights from the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT).

Background: Recent observations suggest statin treatment may be associated with lower mortality in heart failure (HF). The SCD-HeFT was a study of 2521 functional class II and III HF patients with left ventricular ejection fractions < or = 35% and ischemic and nonischemic cardiomyopathy followed up for a median of 45.5 months.

Placebo and nocebo in cardiovascular health: implications for healthcare, research, and the doctor-patient relationship.

Despite treatments proven effective by sound study designs and robust end points, placebos remain integral to elicit effective medical care. The authenticity of the placebo response has been questioned, but placebos likely affect pain, functionality, symptoms, and quality of life. In cardiology, placebos influence disability, syncope, heart failure, atrial fibrillation, angina, and survival.