Hypertrophic cardiomyopathy complicated by complete heart block. Case report and review of the literature.

A 48-year-old man with symptoms of presyncope and congestive cardiac failure had hypertrophic cardiomyopathy (HCM) without obstruction. Complete heart block (CHB), a rare complication of this disease, was preceded by complete left bundle-branch block. Right ventricular (RV) heart failure was a dominant clinical feature but improved dramatically after temporary transvenous RV pacing prompting the insertion of a permanent RV inhibited pacemaker. Repeated ventricular fibrillation was successfully controlled by amiodarone. This is the seventh case of HCM complicated by CHB reported in the literature, and the first in which RV endomyocardial biopsies were undertaken. Two other patients reported in the literature had RV inhibited permanent pacemakers implanted, and a further 2 had atrioventricular sequential pacemakers.