Effects of Infusion of Acetylcholine on Pulmonary Vascular Resistance in Patients with Pulmonary Hypertension and Congenital Heart Disease

Abstract

Survival following surgical correction of congenital cardiovascular defects is unlikely if pulmonary hypertension cannot be decreased significantly. Infusions of acetylcholine decreased pulmonary vascular resistance in 6 of 11 patients having pulmonary hypertension associated with atrial or ventricular septal defects. When the acetylcholine was combined with the breathing of oxygen, resistance decreased further. These findings are consistent with the theory that, at some stage, the pulmonary hypertension in cases of congenital heart disease is maintained at least in part by vasoconstriction and therefore is potentially reversible.