Aldosterone blockade attenuates development of an electrophysiological substrate associated with ventricular tachyarrhythmias in heart failure.

Background: Aldosterone blockade reduces sudden cardiac death in heart failure, but the underlying mechanism is unclear.

Objective: This study's aim was to determine whether chronic eplerenone treatment protects against detrimental ventricular electrical remodeling and development of an arrhythmogenic substrate in a rapid ventricular pacing (RVP)-induced heart failure model.

Methods: Dogs were assigned randomly to oral placebo or eplerenone treatment and divided into 4 groups: 2 sham-operated (no RVP) and 2 RVP groups.

Selective aldosterone blockade suppresses atrial tachyarrhythmias in heart failure.

Introduction: Renin-angiotensin-aldosterone system activation may be involved in the pathogenesis of atrial arrhythmias in congestive heart failure (CHF). The effects of aldosterone blockade on atrial tachyarrhythmias have not been evaluated. This study's aim was to determine whether selective aldosterone blockade suppresses atrial tachyarrhythmia inducibility and modifies atrial electrical and/or structural remodeling in a canine model of rapid ventricular pacing (RVP)-induced CHF.

Mapping of atrial activation during sustained atrial fibrillation in dogs with rapid ventricular pacing induced heart failure: evidence for a role of driver regions.

Introduction: Dogs with rapid ventricular pacing (RVP)-induced congestive heart failure (CHF) have inducible atrial tachycardia, flutter, and fibrillation (AF). We tested the hypothesis that rapid atrial activation in multiple regions and at different rates is responsible for sustained AF in this CHF model.

Methods And Results: We studied 12 episodes of sustained (>10 minutes) AF induced in 12 dogs with CHF produced by 3-6 weeks of RVP at 230 beats/minute.