Prospective, randomized, placebo-controlled, double-blind. Patients were randomized to 4 grams per day of a PUFA fish oil supplement versus an olive oil placebo. The number of therapeutic discharges were recorded from the ICDs and then confirmed from the recorded electrocardiogram strips with the kinds of arrhythmias which had induced the ICD response. The primary end point, time to first ICD event for ventricular tachycardia or fibrillation (VT or VF) confirmed by stored electrograms or death from any cause, was analyzed by intention to treat.