TRICUSPID atresia constitutes approximately 3 per cent of autopsied cases of cyanotic congenital heart disease and 3 per cent of clinically diagnosed congenital heart lesions in patients under 14 years of age.123 A persistent left superior vena cava (LSVC) draining into the coronary sinus is frequently associated with this and other congenital cardiac malformations. The following case illustrates a problem that may be encountered in the surgical management of tricuspid atresia with an associated LSVC. Case Report A 7-year-old girl was first seen at 7 weeks of age for cyanosis. The abnormal findings included 1+ cyanosis at rest, increasing to. © 1972, Massachusetts Medical Society. All rights reserved.