Prospective controlled randomized trial of prophylactic antiarrhythmic therapy in postmyocardial infarction patients...

In order to assess the effect of prophylactic antiarrhythmic therapy in asymptomatic patients with persistent complex ventricular ectopic activity after myocardial infarction, a prospective controlled trial was started in 1981 and is still ongoing. Until August 1986, 965 consecutive patients less than or equal to 70 hospitalized for acute myocardial infarction were screened without antiarrhythmic drugs by 24-h ECG before discharge from the hospital. In this group, 238 patients (28%) had ventricular arrhythmias Lown class III-IVb during at least 2 of 24 hours; they were randomly assigned to three treatment groups: (1) individualized antiarrhythmic therapy based on efficacy in multiple 24-h ECGs and drug level determinations (starting with mexiletine or quinidine; n = 79), (2) treatment with low-dose amiodarone (200-400 mg/day after a loading phase; n = 73), and (3) no antiarrhythmic therapy (n = 86). The three groups were comparable regarding age, gender, previous infarction, Q-wave infarction, ejection fraction, as well as incidence and severity of ventricular ectopic activity. Follow-up, including 24-h ECGs, was performed after 3, 6, and 12 months. Based on the results of this study which will be completed by the end of June 1988, it should be possible to estimate the benefit--or harm--of antiarrhythmic drug therapy as well as its cost in postmyocardial infarction patients with asymptomatic ventricular ectopic activity and to decide whether such treatment may improve survival.