Staged Norwood operation for patients with hypoplastic left heart syndrome and cor triatriatum: a report of two cases.

Two patients with hypoplastic left heart syndrome (HLHS) concomitant with cor triatriatum underwent the staged Norwood procedure following hybrid palliation. Cor triatriatum was diagnosed after birth in both cases. Case 1 with aortic stenosis and mitral atresia underwent bilateral pulmonary artery banding at 2 days of age. Subsequently, balloon atrial septostomy was conducted at 21 days of age due to hypoxia and increased intra-atrial pressure gradient. At 2 months of age, concomitant Norwood operation, cor triatriatum repair, and tricuspid valve repair were successfully performed. She has suffered from branch pulmonary artery hypoplasia since then; thus, Fontan operation was out of indication. Case 2 with aortic stenosis and mitral stenosis underwent bilateral pulmonary artery banding at 6 days of age. After that, the patient's hemodynamic condition remained stable. The Norwood operation concomitant with cor triatriatum repair was performed at 2 months of age. However, during the procedure, massive pulmonary edema and hemorrhage occurred right after the initiation of cardiopulmonary bypass. She could not be weaned from cardiopulmonary bypass.