Congestive heart failure after acute myocardial infarction in patients receiving antiarrhythmic agents for ventricular premature complexes (Cardiac Arrhythmia Pilot Study)

Although patients with severely impaired ejection fraction were excluded, new or worsened congestive heart failure was common in follow-up during CAPS, and sixty-one of 502 patients required hospitalization for CHF in the 1-year follow- up.

Abstract

The Cardiac Arrhythmia Pilot Study (CAPS) was a randomized, double-blind trial of antiarrhythmic drugs (encainide, flecainide, moricizine, imipramine and placebo) in 502 patients with an ejection fraction greater than 0.20 and at least 10 ventricular premature complexes/hour, 6 to 60 days after acute myocardial infarction. Patients were followed for 1 year and the incidence of new or worsened congestive heart failure (CHF) was evaluated. Heart failure in the 1-year follow-up was gauged by the development (in order of increasing severity) of new symptoms (grade 1), the need for a change in therapy, including addition of digitalis, addition or increase of dose of diuretics or afterload reduction agents or discontinuation of beta-blocking agents (grade 2), or by hospitalization (grade 3). Sixty-one of 502 patients (12%) required hospitalization for CHF in the 1-year follow-up. One hundred five of 403 patients (26%) in the active treatment group and 18 of 99 patients (18%) in the placebo group (difference not significant) developed CHF requiring hospitalization or a change in therapy or both. Although patients with severely impaired ejection fraction were excluded, new or worsened CHF was common in follow-up during CAPS.