Neonatal aortic stenosis.

Abstract

Aortic stenosis in the neonate has been associated in the past with a high operative mortality. As a result, in the current era of percutaneous balloon dilatation, the optimal mode of therapy remains controversial. An approach of stabilization with cardiopulmonary bypass, followed by relief of left ventricular outflow tract obstruction, was used at three institutions, and the results are presented. During the period 1983 to 1989, 40 neonates with isolated aortic stenosis and patent ductus arteriosus or coarctation of the aorta, or both, underwent operative therapy. Ages ranged from 1 to 30 days, median of 12 days, including 17 patients in the first week of life. There were 30 boys and 10 girls; weights ranged from 2.5 to 5.5 kg with a mean of 3.6 kg. 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. There have been five reoperations, with one late death in a patient requiring mitral valve replacement and an apical-aortic conduit. One sudden death occurred; autopsy revealed endocardial fibroelastosis. Results demonstrate that in the three institutions using the methods described, a high operative and late survival rate is possible. The results of this technique, against which percutaneous dilatation should be compared, are standard in the current era.