Survival after cardiac arrest or sustained ventricular tachycardia in patients with hypertrophic cardiomyopathy

OBJECTIVES The aim of this study was to evaluate the survival of patients w ith hypertrophic cardiomyopathy (HCM) after resuscitated ventricular fibril lation or syncopal sustained ventricular tachycardia (VT/VF) when treated w ith low dose amiodarone or implantable cardioverter defibrillators (ICDs). BACKGROUND Prospective data on clinical outcome in patients with HCM who su rvive a cardiac arrest are limited, but studies conducted before the widesp read use of amiodarone and/or ICD therapy suggest that over a third die wit hin seven years from sudden cardiac death or progressive heart failure. METHODS Sixteen HCM patients with a history of VT/VF (nine male, age at VT/ VF 19 +/- 8 years [range 10 to 36]) were studied. Syncopal sustained ventri cular tachycardia/ventricular fibrillation occurred during or immediately a fter exertion in eight patients and was the initial presentation in eight. One patient had disabling neurologic deficit after VT/VF. Before VT/VF, two patients had angina, four had syncope and six had a family history of prem ature sudden cardiac death. After VT/VF all patients were in New York Heart Association class I or II, three had nonsustained VT during ambulatory ele ctrocardiography and II had an abnormal exercise blood pressure response. A fter VT/VF eight patients were treated with low dose amiodarone and six rec eived an ICD. Prophylactic therapy was declined by two patients. RESULTS Mean follow-up was 6.1 +/- 4.0 years (range 0.5 to 14.5). Cumulativ e survival (death or ICD discharge) for the entire cohort was 59% at live y ears (95% confidence interval: 33% to 84%). Thirteen (81%) patients were al ive at last follow-up. Two patients died suddenly while taking low dose ami odatone, and one died due to neurologic complications of his initial cardia c arrest Three patients had one or more appropriate ICD discharges during f ollow-up; the times to first shock after ICD implantation were 23, 197 and 1,124 days. CONCLUSIONS This study shows that patients with HCM who survive an episode of VT/VF remain at risk for a recurrent event. Implantable cardioverter def ibrillator therapy appears to offer the best potential benefit regarding ou tcome. (C) 1999 by the American College of Cardiology.