Survival after systemic to pulmonary arterial shunts in infants less than 30 days old with obstructive lesions of the right heart chambers.

Ninety-seven infants less than 30 days old with obstructive lesions of the right heart chambers underwent palliative surgery from 1950 through 1972. The diagnosis was made at cardiac catheterization and confirmed at operation or subsequent autopsy. Because of unavailability of complete preoperative studies and sufficient blood gas data, 36 patients presenting between 1950 and 1965 (Group I) were analyzed for surgical risk only. In 61 patients who underwent palliative procedures between 1966 and 1972 (Group II) a more detailed analysis was done. In this group, 31 had a Potts shunt, 29 a Waterston shunt and 1 a Blalock-Taussig shunt. The most frequently encountered malformation was severe tetralogy of Fallot (30 percent) with or without pulmonary atresia, followed by pulmonary atresia with intact ventricular septum (25 percent). The overall surgical mortality rate in patients seen after 1965 (Group II) was 34 percent compared with the 78 percent mortality rate in patients seen earlier (Group I). The surgical mortality in infants operated on during the 1st week of life was double that of those operated on in the 2nd through 4th weeks. Survivors were compared with nonsurvivors for timing of surgery, age at presentation and clinical profile. Only two significant differences were found. Preoperative continuous murmurs were more common in those who survived operation (13 of 40 patients) than in those who died (2 of 21). Arterial pH during cardiac catheterization was the best predictor of subsequent survival, nonsurvivors having significantly greater metabolic acidosis. Palliation of these severe lesions still carries a high mortality rate to which must be added the risk of subsequent repair. Our data suggest that primary repair is to be preferred if it can be undertaken with a risk approximating that of palliative procedures.