Implantable Cardioverter-Defibrillator Therapy for Primary Prevention of Sudden Cardiac Death: An Argument for Restraint

Although it is estimated that a total of 220,000 patients undergo implantable cardioverter-defibrillator (ICD) implantation per year, only 10% to 20% of these patients experience life-saving therapy; this leaves up to 90% of the targeted population as "nonresponders," who do not derive clinical benefit but incur all of the risks from ICD implantation. This article reviews the landmark primary prevention trials to assess the incidence of sudden death and the absolute magnitude of benefit derived from ICD therapy. The discrepancy between trial patients and real-world implementation of ICD therapy is examined, and the potential for risks incurred from ICD implantation is presented. The natural history of patients who receive appropriate ICD therapy and the durability of ICD benefit with respect to cost-effective analyses are discussed, to support the authors' position that ICD therapy should not be routinely used for the primary prevention of sudden cardiac death.