Amiodarone in refractory life-threatening ventricular arrhythmias.

Ninety-six patients with life-threatening ventricular arrhythmias refractory to two or more conventional agents were treated with amiodarone and followed for 6 to 40 months (mean, 15 months). Currently, 75 are alive and well. Seven patients died from nonarrhythmic and five from arrhythmic causes. Nonfatal arrhythmias recurred in four patients, one with early and three with late onset. Intolerable side effects occurred in five patients but heart failure was not aggravated by the drug. On 24-hour Holter recordings done before and serially during therapy in 72 patients, amiodarone eliminated episodes of ventricular tachycardia and complex ectopy and reduced total ectopic beat counts by 90% or more in all but 4 patients. In contrast, ventricular tachycardia inducible by programmed electrical stimulation was suppressed in only 50% of patients, but failure of such suppression did not compromise an excellent clinical outcome. Thus, amiodarone is highly effective in the prophylaxis of recurrent refractory life-threatening ventricular arrhythmias.