Tricuspid valve closure in pulmonary atresia and important RV-to-coronary artery connections.
Mortality is high for children with pulmonary atresia, intact ventricular septum, and important connections between the right ventricle and the coronary arteries because of myocardial ischemia: in systole, suprasystemic right ventricular pressure delivers deoxygenated blood to the coronary artery (or arteries) and in diastole, the right ventricle provides a lower resistance alternative to coronary perfusion of the myocardium. Tricuspid valve closure was performed in 10 such children. None had stenosis of native coronary arteries. A trial of tricuspid valve closure (by balloon) was performed in the cardiac catheterization laboratory in 5 of 10 patients. Seven of 10 children survived surgical closure of the tricuspid valve plus concurrent procedures; none had heart block. Two of the 3 nonsurvivors were probably in inoperable condition due to preoperative myocardial ischemia. Before operation, 4 patients had ischemic changes on electrocardiograms; these changes were abolished after operation. Three of 10 patients have had a Fontan operation with 2 survivors. We conclude that children with pulmonary atresia, intact ventricular septum, important connections between the right ventricle and the coronary arteries, and normal native coronary arteries should have surgical closure of the tricuspid valve within the first year of life and treated thereafter as patients with "tricuspid atresia."