Cyanosis After Surgical Closure Under Direct Vision of Atrial Septa1 Defects

¹ Surgical Clinic of the University of Rome

Three patients with atrial septal defects are reported in whom postoperative cardiac catheterization revealed the elimination of left-to-right shunt and the first appearance of peripheral artery desaturation. This was already apparent at the pulmonary venous level and cyanosis was therefore not sustained by intracardiac right-to-left shunts. In two of these, pulmonary vascular thrombosis was invoked as a cause of pulmonary vein desaturation, the mechanism presumably being a postoperative discrepancy between expanded pulmonary bed and decreased blood flow, conducive to stasis and stagnant thrombosis. There was no apparent explanation in the third patient.

It is felt that detailed pre- and postoperative investigation of the respiratory function, in particular of the diffusing capacity of the lungs, might help in the understanding of the reported unusual behavior.