4 Cases of Midventricular Obstructive Hypertrophic Obstructive Cardiomyopathy

ABSTRACT

In hypertrophic cardiomyopathy, the distribution and extent of left ventricular hypertrophy is known to be variable. Among the subtypes of hypertrophic cardiomyopathy, midventricular obstruction is a rare variant of obstructive hypertrophic cardiomyopathy. This variant is at higher risk of apical wall motion abnormality and/or infarction. We report 4 patients with midventricular obstructive hypertrophic cardiomyopathy who presented with chest pain. Significant systolic pressure gradients between basal and apical chamber of left ventricle were documented by cardiac catheterization and Doppler echocardiography in all patients, and left ventricular apical infarction was noted in one of them. During mean follow-up period of 32 months(21 months to 5 years), one patient with apical infarction died of malignant ventricular arrhythmia.