[Evaluation of the anti-arrhythmia effect of intravenous flecainide in supraventricular tachyarrhythmias].

We studied the effects of intravenous flecainide acetate, given as a single dose of 2 mg/kg in no less than 15 minutes, on 31 patients with supraventricular tachyarrhythmias. Fourteen (87%) of the 16 patients with paroxysmal atrial fibrillation converted to sinus node rhythm. All 7 (100%) of the patients with paroxysmal supraventricular tachycardia converted to sinus node rhythm. Five (60%) of the 8 patients with paroxysmal atrial flutter converted to sinus node rhythm. The average time of conversion, after completion of drug administration, was 15 +/- 20 minutes. The QRS was prolonged an average of 82 to 91 milliseconds; in those cases who converted, the PR interval duration was 180 milliseconds average; QT was prolonged an average of 425-450 milliseconds. There were no changes in the JT interval, and we observed no hemodynamic untoward effects.