Interim mortality in pulmonary atresia with intact ventricular septum.

Background: Recent work has focused attention on interim mortality (death after hospital discharge and before second-stage surgery) in hypoplastic left heart syndrome. This study investigates interim mortality in infants undergoing systemic-to-pulmonary artery shunts for pulmonary atresia with intact ventricular septum.
Methods: At two centers in 11 years (January 1991 through December 2001), 35 infants underwent placement of shunts for palliation of pulmonary atresia with intact septum. Patients were identified from the cardiology database at each institution, and data were collected retrospectively. The infants were classified into two groups, with and without severe right ventricular hypoplasia, based on the initial surgical plan (Fontan or two-ventricle repair).
Results: The mean age and weight of the infants were 9 days and 3.1 kg. The right ventricle was severely hypoplastic in 22 of 35 infants. Hospital death occurred in 2 patients (9.1%), 1 with severe right ventricular hypoplasia. The remaining 33 patients form the study population. There were a total of 5 deaths (15%) after discharge and before second-stage operation, all in patients with severe right ventricular hypoplasia. Two patients, 1 with hypoplastic right ventricle, died after second-stage operation.
Conclusions: These data confirm a significant incidence of interim death in infants with pulmonary atresia and hypoplastic right ventricle. The interim mortality rate in the current two-institution study of infants with pulmonary atresia with intact ventricular septum is similar to that in hypoplastic left heart syndrome if all patients are considered (15%), and is somewhat higher (24%) than that for hypoplastic left heart syndrome if only patients with severe right ventricular hypoplasia are considered. This rate of interim death must be considered when different treatment options (such as shunt or transplant) are contemplated.