The Role of the Implantable Cardioverter-Defibrillator for Prevention of Sudden Cardiac Death

Sudden cardiac death, which accounts for approximately 350,000 deaths each year, is a major health care problem. Antiarrhythmic drugs have not been reliable in preventing sudden cardiac death. Although beta-blockers, angiotensin-converting enzyme inhibitors, and revascularization play a role in prevention of sudden cardiac death, the development and subsequent refinement of the implantable cardioverter-defibrillator has made the most important contribution to its management. Several randomized, controlled trials have demonstrated improved survival in patients resuscitated from cardiac arrest. Two recent trials also suggest a role for primary prevention in selected patients with coronary artery disease, ventricular dysfunction, and nonsustained ventricular tachycardia in whom sustained ventricular tachycardia is induced. Further technological refinements and development of new, more sensitive risk stratifiers with a higher positive predictive value for sudden cardiac death will expand the indications for this life-saving therapy.