Hemodynamics of aortic valve atresia.

Hemodynamic data on 12 infants with aortic valve atresia, ranging from 1 to 3 mo of age, are presented. Peripheral arterial oxygen saturations ranged from 19 to 93%. The lowest saturations were found in patients with closed foramen ovales. Increasing age, increasing pulmonary vascular resistance, and a decrease in the pulmonary-to-systemic blood flow ratio all correlated with decreasing systemic arterial oxygen saturation. In seven of the nine infants under 1 mo of age, systemic arterial saturations ranged from 81 to 93%. Thus, we feel that the classification of this lesion as a form of cyanotic congenital heart disease is misleading and prefer to classify aortic valve atresia as an obligatory admixture lesion. Criteria for selection of patients for surgery are discussed and the minimum amount of hemodynamic data needed for stuch selection is outlined.