Prospective, double-blind, placebo-controlled trial of low-dose amiodarone in patients with severe heart failure and asymptomatic frequent ventricular ectopy

Abstract

Sudden cardiac death is a common cause of mortality in patients with congestive heart failure. To determine if low-dose amiodarone could reduce sudden death among these patients, a prospective, placebo-controlled, double-blind pilot trial was conducted. One hundred one patients with ejection fractions p = 0.02) and remained low after 6 months, while there was no change in ventricular ectopy among the patients receiving placebo. Despite the reduction in ectopy, there was no improvement in mortality or decrease in the incidence of sudden death. One-year mortality by Kaplan-Meier analysis was 28% in the group receiving amiodarone and 19% in the group receiving placebo (p = NS). One-year mortality in patients with >75% reduction in ventricular ectopy after 1 month of treatment was 31% versus 17% in patients with p = NS). Although the size of the trial and its statistical power do not eliminate the possibility of a significant reduction in mortality with low-dose amiodarone, any effect is likely to be modest, i.e., <25%. Therefore low-dose amiodarone can be safely administered to patients with severely impaired myocardial function and will significantly suppress spontaneous ventricular ectopy. However, despite arrhythmia suppression, low-dose amiodarone may not reduce or may have only a modest effect on the incidence of sudden death in patients with heart failure and asymptomatic ventricular ectopy.