HYPERTROPHIC CARDIOMYOPATHY - ROLE OF THE IMPLANTABLE CARDIOVERTER-DEFIBRILLATOR

Objectives. We report the occurrence of cardiac events during long-ter m follow-up in patients with hypertrophic cardiomyopathy (HCM) after c ardioverter-defibrillator implantation. Background. The identification of patients at high risk for sudden death and the prevention of recur rence of sudden death in HCM represents a difficult problem. Methods. We retrospectively analyzed the occurrence of cardiac events during fo llow-up of 13 patients with HCM who received an implantable cardiovert er-defibrillator (ICD) because of aborted sudden death (n = 10) or sus tained ventricular tachycardia (n = 3) (group I). Findings were compar ed with those in 215 patients with an ICD and other structural heart d isease or idiopathic ventricular fibrillation (group II). Results. Aft er a mean (+/-SD) follow-up period of 26 +/- 18 months, 2 of 13 patien ts in group I received appropriate shocks. The calculated cumulative i ncidence of shocks was 21% in group I and 66% in group II after 10 mon ths (p < 0.05). We observed a low incidence of recurrence of ventricul ar tachycardia/fibrillation during follow-up in patients with HCM. No deaths occurred. Conclusions. Our data suggest that ventricular tachya rrhythmias may not always be the primary mechanism of syncope and sudd en death in patients with HCM. The ICD seems to have a less important impact on prognosis in patients with HCM than in patients with other e tiologies of aborted sudden death. (C)1998 by the American College of Cardiology.