Amiodarone in long term management of refractory cardiac tachyarrhythmias.

Amiodarone was used in 30 patients with tachyarrhythmias refractory to treatment with several antiarrhythmic agents. In 18 patients with supraventricular arrhythmias (recurrent atrial tachycardia in seven; atrial fibrillation, recurrent in four and persistent in five; Wolff-Parkinson-White syndrome in two), complete control was obtained in eight and marked improvement in eight patients. Conversion of persistent atrial fibrillation to sinus rhythm was documented in three patients. Congestive heart failure improved markedly in three patients who had persistent atrial fibrillation during amiodarone therapy. In 12 patients with tachycardia of ventricular origin effective control was obtained in nine. The incidence of side effects was low. Amiodarone is effective in maintaining sinus rhythm in many patients with both supraventricular and ventricular tachyarrhythmias when standard antiarrhythmic agents have failed.