Indications for implantable cardioverter defibrillator use for primary prevention of sudden cardiac death.

The implantable cardioverter defibrillator (ICD) is used for primary and secondary prophylaxis of sudden cardiac death in high-risk patients. Although several trials have demonstrated the superiority of ICD over standard medical therapy or antiarrhythmic medication in this population, a few trials have not shown survival benefit. This review examines the major ICD trials that provide the basis for current therapy in this rapidly changing and very important area of cardiology.