A rare form of atrioventricular septal defect with severe subaortic stenosis.

An unusual form of atrioventricular septal defect associated with severe subaortic obstruction is reported in a neonate who presented with intractable cardiac failure. The baby had a large defect in the atrioventricular septum allowing communication from the left ventricle to the right atrium, without interatrial or interventricular communication, and a cleft anterior mitral leaflet. The baby expired despite palliative surgery performed to bypass the subaortic stenosis.