Pulmonary atresia, intact ventricular septum, and Ebstein anomaly of the tricuspid valve. Anatomic and surgical considerations.

Pulmonary atresia with intact ventricular septum is a disorder that involves the whole right ventricle. An associated Ebstein deformity of the tricuspid valve is found in 10% of the cases, further complicating the anatomy and the function of the right ventricle. From January 1966 to December 1990, pulmonary atresia, intact ventricular septum, and Ebstein deformity of the tricuspid valve were observed in 11 cases in our institution; four of them were necropsy findings and the remaining seven were patients treated surgically. Of the latter, two were boys and five were girls (age range 1 day to 18 days). Two patients were managed by pulmonary valvotomy, three by systemic-pulmonary artery shunt, and two had a combination of the two. Operative mortality was 57%. Eight hearts were available for morphologic study. All had viscero-atrial situs solitus, D-loop ventricular structure, and normally related great arteries. A correlation between the degree of tricuspid valve dysplasia and right ventricular cavity size was observed in all. Furthermore, in five cases the anterior leaflet of the tricuspid valve obstructed the right ventricle at the ostium infundibuli level. In two of our surgical patients, a protruding anterior tricuspid valve leaflet was identified and excised and both patients survived. Ebstein anomaly of the tricuspid valve further complicates surgical management and outcome of pulmonary atresia and intact ventricular septum. Potential obstruction at the ostium infundibuli level should always be considered during repair. Various degrees of right ventricular inlet dysplasia, always present in this complex, may contraindicate an anatomic correction. In these cases a modified Fontan-type procedure should be considered as a valid surgical option.