A controlled trial of propafenone for treatment of frequent and repetitive ventricular premature complexes

Abstract

The effectiveness of oral propafenone was evaluated for the treatment of ventricular premature complexes (VPCs) in 12 patients, using a singleblind, dose-ranging trial followed by a double-blind comparison with placebo, and then an open-label, long-term protocol. During dose ranging, 8 of 12 patients achieved ≥ 80 % suppression of total VPCs (mean 83%) (p < 0.01 vs single-blind placebo). Paired VPCs were suppressed ≥ 90 % and ventricular tachycardia was eliminated in 11 of the 12 patients (p < 0.01). The effectiveness of propafenone for treatment of VPCs was confirmed during the double-blind trial (p < 0.05 vs double-blind placebo) and during treatment for 6 months (p < 0.05 vs initial single-blind placebo). Propafenone prolonged the PR interval by 16% (p < 0.01 vs single-blind placebo) and the QRS interval by 18 % (p < 0.001). Left ventricular systolic performance decreased as assessed by 2-dimensional echocardiography (p < 0.01 vs single-blind placebo). Propafenone increased serum digoxin levels in 5 of 5 patients (mean increase of 83 %). Side effects included exacerbation of congestive heart failure (1 patient) and conduction abnormalities (2 patients). Thus, propafenone is effective for treatment of total and repetitive VPCs. Although generally well tolerated, the drug reduces left ventricular systolic function and atrioventricular conduction and increases serum digoxin levels.