TRICUSPID-VALVE CLOSURE IN PULMONARY ATRESIA AND IMPORTANT RV-TO-CORONARY ARTERY CONNECTIONS

Mortality is high for children with pulmonary atresia, intact ventricu lar septum, and important connections between the right ventricle and the coronary arteries because of myocardial ischemia: in systole, supr asystemic right ventricular pressure delivers deoxygenated blood to th e coronary artery (or arteries) and in diastole, the right ventricle p rovides a lower resistance alternative to coronary perfusion of the my ocardium. Tricuspid valve closure was performed in 10 such children. N one had stenosis of native coronary arteries. A trial of tricuspid val ve closure (by balloon) was performed in the cardiac catheterization l aboratory in 5 of 10 patients. Seven of 10 children survived surgical closure of the tricuspid valve plus concurrent procedures; none had he art block. Two of the 3 nonsurvivors were probably in inoperable condi tion due to preoperative myocardial ischemia. Before operation, 4 pati ents had ischemic changes on elechrocardiograms; these changes were ab olished after operation. Three of 10 patients have had a Fontan operat ion with 2 survivors. We conclude that children with pulmonary atresia , intact ventricular septum, important connections between the right v entricle and the coronary arteries, and normal native coronary arterie s should have surgical closure of the tricuspid valve within the first year of life and treated thereafter as patients with ''tricuspid atre sia.''