Our review would suggest that patient with tricuspid atresia and transposition of great vessels frequently have a systemic-to-pulmonary blood flow ratio that is compatible with a relatively good prognosis. A few long-term survivors with this combination of defects have been reported in the literature. Jordan and Sanders in 1966 reviewed the world literature and found 19. They added two: one, age 33, with transposition and a ventricular septal defect, the other, age 57, with ventricular septal defect and subpulmonary stenosis. The longest survivor in our group is a 28-years-old man who has led a moderately active life.
Ventricular septal defect was present in the subgroup with transposition of the great vessels. It was of a moderate-to-large size in the majority of patients. It was the presence of this defect which allowed for a near-normal pulmonary blood flow. It appears that although the patients in this group were more anatomically deranged, the combination of these defects allowed for better hemodynamics.
Our clinical results confirm the anatomic findings of Tendon and Edwards. In a postmortem study, they found that when the great vessels were normally related, obstruction to pulmonary flow was common. When they were transposed, obstruction to pulmonary flow was less common.