Regional cardiac sympathetic denervation and systolic compression of a septal perforator branch in a sudden death survivor with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy is a heterogeneous primary cardiac disease with a broad clinical spectrum, including a high risk for sudden death in a certain subgroup of patients. However, the precise criteria for identifying the subgroup at high risk have not been established. The authors describe a 41-year-old man with hypertrophic cardiomyopathy who was examined after an episode of aborted sudden death. Extensive invasive and noninvasive investigations did not reveal a cardiac abnormality other than severe sympathetic denervation in the midbasal septal wall on iodine-123 MIBG SPECT imaging and concentric left ventricular hypertrophy on echocardiography. A retrospective review of the cardiac catheterization findings, however, revealed systolic compression of a septal perforator artery. The aborted sudden death of the patient was most likely associated with systolic compression of a septal branch or sympathetic denervation, which may have precipitated a ventricular arrhythmia in this patient.