Patients who survive life-threatening ventricular arrhythmias are at risk for recurrent arrhythmias. They can be treated with either an ICD or anti-arrhythmic drugs.
	We did a randomized comparison of these 2 treatments in patients who had been resuscitated from near-fatal ventricular fibrillation or who had cardioversion from sustained ventricular tachycardia. Patients with ventricular tachycardia also had either fainting or other serious cardiac symptoms, along with an EF of 40% or less. 
	One group of patients had an ICD implanted and the other group got class 3 anti-arrhythmic drugs, primarily amiodarone. Fifty-six medical centers screened all patients for ventricular tachycardia or ventricular fibrillation fro 4 years. Of 1016 patients, 507 were randomly assigned to get an ICD and 509 to antiarrhythmic-drug therapy. 45% had ventricular fibrillation and 55% had ventricular tachycardia. The primary end point was overall mortality.
	Follow-up was complete for 1013 patients (99.7%). Overall survival was higher with ICD vs drug therapy: 

89% vs 82% at 1 year
82% vs 75% at 2 years
75% vs 64% at 3 years

	Among survivors of ventricular fibrillation or sustained ventricular tachycardia causing severe symptoms, the ICD is superior to anti-arrhythmic drugs for increasing overall survival.

From: N Engl J Med 1997 Nov 27;337(22):1576-83
Authors; The Antiarrhythmics versus Implantable Defibrillators (AVID) Investigators
PMID: 9411221, UI: 98026791 

Comment in: N Engl J Med 1997 Nov 27;337(22):1621-3 
Comment in: ACP J Club 1998 May-Jun;128(3):60-1