AVID and beyond: Lessons learned

Abstract

The implantable cardioverter defibrillator (ICD) has been approved by the Food and Drug Administration since 1985 and is widely used in practice. Until very recently, however, the efficacy of the ICD has depended on large published series of retrospective studies analyzing ventricular tachycardia and fibrillation patients. The recently published antiarrhythmics versus implantable defibrillator (AVID) trial is the first prospective randomized trial to show clearly that the ICD is more effective than drug therapy (amiodarone or sotalol) in patients who have survived an out-of-hospital cardiac arrest or have syncopal or hemodynamically significant ventricular tachycardia. The survival advantages probably holds true only for patients with an ejection fraction under 35% who have either coronary disease or other forms of cardiomyopathy. The survival advantage in this trial – which was halted prematurely because of the results noted – was short-lived (2.6 months) and expensive. The results of this trial will clearly define the role of the ICD in everyday clinical practice and will be of invaluable benefit to patients, physicians, and insurers alike. The results of the AVID trial as well as other post-event and pre-event trials are summarized in the manuscript. A number of substudies have already resulted from the AVID study and are also presented.