Management of neonatal critical pulmonic stenosis in the balloon valvotomy era.

We evaluated our recent experience with management of neonatal critical pulmonic stenosis and intact ventricular septum between 1982 and 1988. Thirty-nine patients (aged less than 3 months) were treated initially by operation (group A, n = 19) or with balloon pulmonary valvotomy (group B, n = 20). Patients in group A were younger (5 +/- 1.3 versus 18 +/- 4 days in group B) (mean +/- standard error of the mean) and had a greater degree of hypoxia (oxygen tension, 55 +/- 4 versus 80 +/- 6 mm Hg) (p less than 0.05 for all variables). Ten patients in group A and 8 patients in group B had right ventricular hypoplasia, based on an angiographically determined index. Balloon pulmonary valvotomy was attempted in 20 patients at the time of the initial catheterization but was unsuccessful in 9 owing to inability to catheterize the hypoplastic right ventricular outflow tract (n = 8) and to recurrent infundibular stenosis (n = 1). Patients with failed balloon valvotomy were subsequently operated on within 24 hours. The early operative mortality (less than 30 days) was 25% (7 of 28); one death (9%) occurred after successful balloon valvotomy owing to associated critical aortic stenosis. The early postoperative gradient was 20 +/- 2 mm Hg; the post-balloon valvotomy gradient was 18 +/- 3 mm Hg. We conclude that balloon pulmonary valvotomy yields good results in patients with critical pulmonary stenosis with essentially normal-sized right ventricle, whereas surgical pulmonary valvotomy is required for patients with right ventricular hypoplasia.