Patent ductus arteriosus with partial reversal of the shunt: A study of two cases

Two cases of patent ductus arteriosus with intermittent reversal of the shunt are described. The bidirectional flow was demonstrated during life by cardiac catheterization, simultaneous right brachial artery and femoral artery blood oxygen analyses, oximetric and dye dilution studies, and by angiocardiography. The clinical picture and laboratory findings to be expected in cases of ductus arteriosus with intermittent reversal of the shunt are presented and the extremely high operative mortality in such cases is stressed. Finally, the possible pathogenesis of the marked pulmonary hypertension is discussed briefly.