Neonatal aortic stenosis.

Perioperative conditions included congestive heart failure in 38 and mitral regurgitation in 16; left ventricular-aortic gradients ranged from 15 to 130 mm Hg, with a mean of 67 mm Hg. There were 30 open valvotomies and 10 transventricular dilatations. The hospital survival rate was 87.5% (35/40) with no significant difference between the methods of valvotomy (9/10 in the transventricular dilatation group, 90%; 26/30 in the open valvotomy group, 87%). Although multiple methods of perfusion and valvotomy were used, the single unifying factor of cardiopulmonary bypass stabilization was present in all 40 patients. No significant difference in survival was noted between institutions, methods of cardiopulmonary bypass, cardiopulmonary bypass times, crossclamp times, or method of valvotomy