Cor triatriatum (subdivided left atrium).

Twenty-one patients (age 1 day to 156 months) with cor triatriatum sinister (subdivided left atrium) were treated over a 23 year period at two institutions. Anatomic classification of the hearts revealed 20 (95%) with classical cor triatriatum and normal pulmonary venous connections. One other patient had partial anomalous pulmonary venous connection. Three of these patients (14%) had other severe associated cardiac anomalies. Surgical correction of isolated cor triatriatum was performed in 13 patients of whom eight (62%) survived. Long-term results were excellent in seven (88%) patients; one late death occurred. A right atrial approach for infants and small children is recommended, while the left atrial approach appears satisfactory for larger children.