AVID AND BEYOND - LESSONS LEARNED

The implantable cardioverter defibrillator (ICD) has been approved by the Food and Drug Administration (FDA) since 1985 and is widely used i n practice. Until recently, however, the efficacy of the ICD has depen ded on a large published series of retrospective studies analyzing ven tricular 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 mor e effective than drug therapy (amiodarone or sotalol) in patients who have survived an out-of-hospital cardiac arrest or have syncopal or he modynamically significant ventricular tachycardia. The survival advant ages probably hold true only for patients with an ejection fraction un der 35% who have either coronary disease or other forms of cardiomyopa thy. The survival advantage in this trial--which was halted prematurel y because of the results noted--was short-lived (2.8 months) and expen sive. The results of this trial will clearly define the role of the IC D in everyday clinical practice and will be of invaluable benefit to p atients, physicians, and insurers alike. The results of the AVID trial , as well as other postevent and pre-event trials, are summarized in t his article. A number of substudies have already resulted from the AVI D study and are also presented. (J Interven Cardiol 1998;11:217-226).