Ebstein's anomaly: a report of 3 cases in the dog.

Three young unrelated dogs were diagnosed as having the canine counterpart of Ebstein's anomaly, an eponymic term for a cardiac malformation in man. All of the dogs had systolic murmurs in the tricuspid area, and all had radiographic evidence of cardiac enlargement, particularly of the right atrium. Electrocardiography indicated atrial disease or right atrial enlargement and right ventricular conduction defects. The defect was confirmed by means of cardiac catheterization in all 3 dogs. Open heart surgery was performed on 2 of the dogs--plastic reconstruction of the tricuspid annulus and placement of a prosthetic valve in 1 and closure of an atrial septal defect in the other; both of these dogs died (1 day and 1 month after surgery).