Preventing sudden cardiac death.

The syndrome of sudden cardiac death, which claims the lives of hundreds of thousands of Americans each year, is usually caused by ventricular tachycardia or fibrillation. Electrophysiologic testing is now being used to prevent recurrence of this syndrome in successfully resuscitated persons. With this procedure, antiarrhythmic drugs are assessed in terms of their ability to prevent induction of sustained ventricular tachyarrhythmias, rather than their ability to merely suppress ventricular premature beats. In medically unresponsive patients, an automatic cardioverter-defibrillator can be implanted to provide maximal protection from sudden cardiac death caused by ventricular tachyarrhythmias.