Comparison of propafenone and disopyramide in the treatment of ventricular premature complexes: a randomized double blind crossover placebo controlled trial.

To determine the efficacy of the newer antiarrhythmic drug propafenone and to compare it to disopyramide, sixteen patients--11 men and 5 women--participated in a randomized double-blind crossover placebo-controlled trial using 150 mg quid of propafenone or disopyramide. Twenty-four hour ECG's were performed at the end of the placebo period and each 2 weeks of drug therapy. Droupouts (2) because of adverse effects were not included in analysis. On placebo there were 485 +/- 535 (mean +/- SD) ventricular premature complexes (VPC's)/hour. Propafenone significantly (p = 0.010) reduced VPC's to a slightly smaller amount 182 +/- 298/hour. There was no significant difference between propafenone and disopyramide in suppressing VPC's, however, analysis of the circadian rhythm of VPC's showed a greater reduction in VPC's from 1600 to 2400 hour after propafenone compared to disopyramide using this dose regimen. Using a criterion of efficacy of greater than 80% reduction in VPC's, 8/14 patients had a good suppression with propafenone, 3 patients responded only to propafenone, 4 patients only to disopyramide, 5 patients to both and 2 patients to neither. Using a criterion of efficacy of greater than 65% reduction in VPC's 11/14 patients had good suppression with propafenone or disopyramide, 3 patients responded only to propafenone and 4 patients only to disopyramide. Side effects were more common with disopyramide. Two patients dropped out after disopyramide because of gastrointestinal symptoms. Side effects were found in 11/14 remaining patients on disopyramide, but in 6/14 on propafenone.(ABSTRACT TRUNCATED AT 250 WORDS)