Systemic obstruction in univentricular hearts: surgical options for neonates

The surgical management for bridging patients with univentricular heart and systemic obstruction to a Fontan procedure remains controversial.

Twenty-seven of 96 patients with univentricular heart and unobstructed pulmonary blood flow referred for surgical palliation were seen with systemic obstruction. Twenty-six were neonates with coarctation of the aorta in 21 and subaortic stenosis in 5. In 8 other patients, subaortic stenosis developed after initial pulmonary artery banding. Four different palliative procedures were performed: coarctation repair with pulmonary artery banding (group I, n = 15); Norwood or Damus-Kaye-Stansel or arterial switch operation (group II, n = 9); coarctation repair with pulmonary artery banding and bulboventricular foramen enlargement (group III, n = 2); and orthotopic heart transplantation with coarctation repair (group IV, n = 1).

The mortality rate was 34.3% (n = 12) for all patients, 53.3% in group I, 33.3% in group II (p = 0.003 versus group I), and 50% in group III. Nine patients (8 in group I and 1 in group II) had development of subaortic stenosis and underwent a subsequent procedure: Damus-Kaye-Stansel operation in 5, arterial switch operation in 3, and bulboventricular foramen enlargement in 1. Three had a concomitant or subsequent Fontan procedure and 2, a bidirectional Glenn procedure. In group II, 1 patient underwent a subsequent Fontan procedure and another, a bidirectional Glenn anastomosis. Six of the 8 patients with subaortic stenosis after initial pulmonary artery banding underwent a second stage consisting of a Damus-Kaye-Stansel procedure (n = 3), bulboventricular foramen enlargement (n = 2), or creation of an aortopulmonary window (n = 1). Three had a concomitant Fontan procedure and 2, a bidirectional Glenn procedure. Actuarial 4-year survival was 65.5% +/- 8.4% (70% confidence limits) for all patients; it was 40% +/- 13.3% in group I and 66.6% +/- 16.3% in group II (p < 0.05).

Initial management of patients with univentricular heart and systemic obstruction by Norwood-like procedures provides a better outcome. Success of the Fontan operation relies on the ability to provide timely relief of subaortic stenosis.