Fetal severe aortic regurgitation due to absence of left coronary leaflet of aortic valve

Congenital absence of aortic valve cusps is a rare congenital heart malformation, which is commonly associated with other cardiac defects. Isolated absence of aortic valve or one leaflet is extremely rare and has not been described antenatally. We present the first case of a fetus with isolated congenital severe aortic regurgitation from absent aortic cusp and pathological specimen of this rare entity. On fetal echocardiography at 19 weeks of gestation, there were dilated aortic root and severe aortic regurgitation causing ‘to and fro’ colour flow signals across left ventricular outflow. This caused severe LV systolic dysfunction, significant ventricular dyssynchrony and cardiomegaly. On fetal autopsy, aortic root was dilated. Left coronary cusp was absent while other cusps showed mild thickening. Left ventricle was dilated and hypertrophied. Pulmonary valve leaflets were normal.