Right ventricular pacing for right ventricular outflow tract obstruction in a man with biventricular hypertrophic cardiomyopathy.

A 40-year-old man with known hypertrophic cardiomyopathy presented with syncope after coughing. Physical examination revealed a systolic murmur that was accentuated by the Valsalva maneuver. An electrocardiogram suggested biventricular hypertrophy and biatrial enlargement (Fig. 1). Echocardiograms revealed asymmetric septal hypertrophy with a diastolic septal thickness of 2.3 cm, and evidence of flow acceleration across the right ventricular outflow tract (RVOT) and left ventricular outflow tract (LVOT) (Figs. 2 and 3). Cardiac magnetic resonance images confirmed noncontiguous hypertrophy involving the basal septal, basal anterior, and apical walls of the left ventricle, as well as the inferior and free walls of the right ventricle (RV). A prominent muscle band in the RVOT contributed to dynamic obstruction across the RVOT (Figs. 4 and 5). Patchy hyperenhancement in the septum, visible in delayed-enhancement sequences after Images in Cardiovascular Medicine