Morphology of Pulmonary Stenosis in Four Calves

Abstract

Pulmonary stenosis with intact ventricular septum was observed in 4 (0.6%) of 670 bovine hearts showing congenital cardiovascular anomalies. In cases 1 to 3 the hearts showed valvular pulmonary stenosis. In these hearts the annulus of the valve was narrowed by hypoplasia of the right semilunar valve and right sinus of pulmonary trunk. Case 3 showed fusion of the commissura between right and intermediate semilunar valves. Case 4 showed valvular, supravalvular and infundibular pulmonary stenosis. In this heart the annulus of the valve was narrowed, and hypoplasia of the pulmonary trunk and infundibulum was recognized.