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Surgery for critical aortic stenosis in newborns is still good therapy after 25 years.

Because of the high operative mortality in newborn infants with critical aortic stenosis, new therapeutic modalities have emerged. The authors reviewed their results of surgery for this condition in newborn infants between January 1964 and December 1990. Thirty-seven infants were operated on for critical aortic stenosis, which was diagnosed at a mean patient age of 14.5 days. The surgical procedure was done at a mean patient age of 37 days. Five infants died intraoperatively of ventricular fibrillation at the time of incision. Transventricular valvotomy was attempted in 4 infants, and the remaining 28 infants underwent transaortic valvuloplasty. Overall survival improved markedly in the last 5 years of the study, from 31% to 75%. All patients who had transventricular valvotomy died, as did the only infant with previous percutaneous aortic valvuloplasty. Of the infants who died, 38% weighed less than 3000 g at the time of operation compared with 13% of the survivors (p < 0.05). The duration of cardiopulmonary bypass was also identified as a risk factor (p = 0.001). Of the surviving infants, 93% were followed up at a mean of 66 months. All but one were in New York Heart functional class I or II. The following risk factors were identified for operative mortality: year of surgery, preoperative hemodynamic condition, associated anomalies of the left ventricle, surgical weight less than 3000 g, transventricular valvotomy, year of surgery and prolonged cardiopulmonary bypass. Because of the much improved survival recently, surgery remains a good therapeutic choice for critical aortic stenosis in the newborn infant.