[Efficacy of propafenone in the treatment of ventricular hyperkinetic arrhythmias in subjects with a history of myocardial infarction].

A placebo-controlled single-blind study was performed to evaluate the efficacy of oral propafenone on stable potentially malignant ventricular tachyarrhythmias in 13 patients who had suffered a myocardial infarction two months or longer before the trial. All patients exhibited at a 24 hour Holter monitoring a minimum mean frequency of 10 ventricular premature depolarizations (VPDs) per hour and repetitive VPDs. Ventricular tachyarrhythmias characterization was obtained by means of multiple Holter monitorings and exercise stress testings. Propafenone was considered as effective when a well-defined quantitative and qualitative reduction of ventricular tachyarrhythmias was reached. After an initial placebo phase, patients received propafenone 450 mg or 900 mg daily. Acute effectiveness of propafenone was proved in 8 on 13 patients (62%) who showed a significative reduction of VPDs (89%, p less than 0.02) and a suppression of the most complex forms of ventricular tachyarrhythmic events. The efficacy of propafenone was confirmed, three months later, in each patient, side effects were infrequent, minimal and of no clinical consequence. Oral propafenone can be considered as an effective drug for reducing the level of potentially malignant ventricular tachyarrhythmias in patients with previous myocardial infarction.