Propafenone versus amiodarone in field treatment of primary atrial tachydysrhythmias.

Thirty-nine patients with paroxysmal atrial fibrillation or supraventricular tachycardia randomly received amiodarone or propafenone intravenously at home. Fifteen patients received amiodarone and 24 received propafenone; 87.5% of the patients who received propafenone and 40% of the patients who received amiodarone were converted at home to sinus rhythm (P less than .005). The median time of conversion was 10 minutes (range 5 to 35) for propafenone and 60 minutes (range 20 to 130) for amiodarone (P less than 0.005). When either drug failed to terminate atrial tachydysrhythmias at home, the same drug always restored sinus rhythm with subsequent oral treatment during hospitalization. No major side effects were observed after the infusion of either drug. The incidence of minor side effects was not significantly different between the two drugs. Both the drugs are efficacious and safe in the acute management of primary supraventricular tachydysrhythmias. Propafenone showed a greater rapidity of action.