Prognostic factors in valvotomy for critical aortic stenosis in infancy.

ABSTRACT

Aortic valvotomy for critical aortic stenosis in infancy has had a high mortality. To determine the factors that influence survival, we reviewed the cases of 24 infants who underwent aortic valvotomy in the first 6 months of life (mean 4 1/2 weeks) for aortic stenosis from 1978 to 1984. Cardiopulmonary bypass was used in all patients. Operative mortality was 21% (5/24), four of the five deaths occurring from low cardiac output. Analysis of preoperative factors affecting survival versus nonsurvival revealed that low ejection fraction (60% +/- 17% in survivors versus 36% +/- 2% in nonsurvivors), high left ventricular end-diastolic pressure (16 +/- 7 mm Hg in survivors versus 30 +/- 14 mm Hg in nonsurvivors), and presence of endocardial fibroelastosis (25% in survivors versus 100% in nonsurvivors) all were predictive of a poor outcome, although the small sample size indicated caution in interpreting results. Factors that did not appear to influence survival included peak systolic gradient (79 +/- 30 mm Hg in survivors versus 60 +/- 15 mm Hg in nonsurvivors) and left ventricular end-diastolic volume (37 +/- 17 cm3/m2 in survivors versus 36 +/- 7 cm3/m2 in nonsurvivors). Four patients with a left ventricular end-diastolic volume below 26 cm3/m2 survived. Postoperative gradients averaged 25 +/- 21 mm Hg at 3.4 +/- 2 years' follow-up in nine recatheterized patients. Ejection fraction of these patients increased from 45% +/- 10% to 70% +/- 11% and left ventricular end-diastolic volume increased from 37 +/- 17 to 58 +/- 5 cm3/m2. Two of 17 patients have required apical-aortic conduits; all other patients are asymptomatic. We conclude that infants with critical aortic stenosis benefit from valvotomy even with impaired left ventricular function and severely reduced left ventricular dimensions and many have nearly normal hemodynamics on late follow-up.