Abstract 19528: ICD in Hypertrophic Cardiomyopathy: Outcome and Complications
Background: The use of implantable cardioverter defibrillator (ICD) in selected patients (pts) with hypertrophic cardiomyopathy (HCM) at risk for sudden death (SCD) is accepted, but there may be a high risk for device complications and inappropriate therapies given the long duration of therapy, younger pts, and their higher activity.
Methods: Of 718 pts evaluated in our HCM Program from 1994 to 2010, 90 pts (12.5%) received an ICD at our institution for primary (n=86) or secondary (n=4) prevention. Outcomes and complications were analyzed during follow-up of 4.1±3.3 yrs. We excluded from analysis pts implanted before our initial evaluation.
Results: At time of implantation, the 90 pts were 47±16 yrs, 64% male, LVEF 67±8%, septal thickness 27±7 mm, LVOT gradient 37±49 mmHg, 36 (40%) with rest gradient ≥ 30 mm Hg, 24 (27%) history of afib. Primary prevention risk factors included family history of SCD in 31 (36%), unexplained syncope in 44 (51%), NSVT in 37 (43%), septum ≥ 30 mm in 24 (28%), and abnormal blood pressure response to exercise in 18 (21%); 32 (37%) pts had less than 2 risk factors. Medication included beta-blockers in 89%, calcium channel blockers in 22%, disopyramide in 19% and other antiarrhythmics in 23%. There were 2 deaths, 1 sudden and 1 non-cardiac (0.5% per year). Appropriate therapy or sudden death occurred in 12/90 pts (13.3%) - 11/86 for primary prevention and 1/4 for secondary prevention. Complications occurred in 29/90 (32%): procedure-related in 9 (10%), late lead malfunction in 10 (11%) and inappropriate therapy in 18 (20%) - shocks in 17 (19%).
Conclusions: In this large cohort of HCM pts, primary prevention treatment with ICD was associated with clinically relevant appropriate therapy rate. However, use of ICD was associated with relatively high rate of complications, most prominently inappropriate ICD shocks. Thus, for many pts, the decision of whether or not to implant for primary prevention should depend on physician judgment and patient choice.
- © 2010 by American Heart Association, Inc.