RESUMO
Midventricular obstructive hypertrophic cardiomyopathy (MOHCM) is a rare variant of hypertrophic cardiomyopathy. Apical dilatation and myocardial infarction can be complicated without significant coronary artery disease. We report a case of apical dilatation in a patient with MOHCM without atherosclerotic coronary artery disease. A 76-year-old woman was admitted for recent cerebral infarction and consulted to cardiologist for abnormal electrocardiographic findings. She had been suffering from exertional dyspnea (NYHA II) for about four years. Two dimentional-echocardiography revealed midventricular obstructive hypertrophy with an apical dilatation and paradoxical jet flow from the apical aneurysm to the left ventricular outflow tract during early diastole. Cardiac catheterization demonstrated dyskinesia in the apical wall with midventricular obstruction and a peak-to-peak intraventricular pressure gradient of 110 mmHg during pull-back from the apical high-pressure chamber to the subaortic low-pressure chamber in the left ventricle. Coronary angiograms showed no significant stenotic lesion of the coronary arteries. She was prescribed oral beta-adrenergic antagonist to decrease the intraventricular pressure gradient.