Bilateral Ebstein's Malformation Associated with Multiple Orifices in the Atrioventricular Valves.

Ebstein's malformation involving both atrioventricular valves is a very rare entity. We report two cases in which the atrioventricular valves were also associated with multiple orifices. The first was an adult with known congenital heart disease. The true nature of the valvar malformation, associated with atrioventricular septal defect, was only discovered at autopsy. The second case was a neonatal heart specimen associated with hypoplastic left ventricle and aortic atresia. A review of the literature showed that Ebstein's malformation was rarely associated with atrioventricular septal defect. While accessory orifices were common in the left atrioventricular valve, they were rarely found in the right atrioventricular valve. Our cases, therefore, showed a very rare combination of seemingly disparate defects at the level of the atrioventricular junction.