Mid-ventricular obstruction occurred in hypertrophic left ventricle of heterozygous Fabry's disease-Favorable effects of cibenzoline: A case report.

A 54-year-old woman visited our hospital because of palpitation and dizziness. Systolic ejection murmur, Levine IV/VI, was heard at the left sternal border and atrial gallop was auscultated at apex. Echocardiogram demonstrated diffuse hypertrophy of the left ventricular walls extending to the apex. The left ventricular walls increased symmetrically; the septal and the posterior wall measured approximately 26 mm and 30 mm in thickness, respectively. Apical two-chamber views revealed a narrow outflow of the left ventricular cavity at apex with a distinct convergence zone, where color flow Doppler imaging showed turbulent jet flow from mid to late systole. The leukocyte α-galactosidase A activity was lower than normal. Percutaneous endomyocardial biopsy showed specific change for Fabry's disease by electron microscopy. On cardiac catheterization, mid-ventricular resting pressure gradient of approximately 90 mmHg was shown. This pressure gradient dramatically disappeared after intravenous administration of 70 mg of cibenzoline. We describe a rare case of Fabry's disease that revealed diffuse hypertrophy having dynamic obstruction at mid-left ventricle, like mid-ventricular obstruction, and the administration of cibenzoline had beneficial effects on pressure gradient of mid-left ventricle.