Primary prevention of sudden cardiac death.

Sudden cardiac death (SCD) is the leading cause of death in the United States. Although SCD occurs most commonly in patients with established heart disease, SCD can also be the initial manifestation of cardiovascular disease. Efforts to reduce the incidence of SCD include aggressive treatment of heart disease and its risk factors with pharmacologic and nonpharmacologic strategies. Public health measures to improve the response to cardiac arrest, including dissemination of automated external defibrillators in the community, are extremely important. Implantation of implantable cardioverter defibrillators (ICDs) in patients at high risk of SCD improves survival in these patients. Clinical trials have identified patients with ischemic and nonischemic cardiomyopathy who may benefit from prophylactic ICD implantation.