Use of ATP-MgCl2 in the evaluation and treatment of children with pulmonary hypertension secondary to congenital heart defects

Abstract

Background. Pulmonary hypertension results in increased morbidity and mortality in children after surgical repair of congenital heart defects. Various vasodilators have been unsuccessful in providing preferential pulmonary vasodilation in these patients. Identification of a more preferential pulmonary vasodilator would improve the assessment, management, and outcome of these children. To determine whether ATP-MgCl2 is a preferential pulmonary vasodilator in children with pulmonary hypertension secondary to congenital heart defects, ATP-MgCl2 was administered during routine cardiac catheterization, and the effects were compared with tolazoline. In addition, ATP-MgCl2 was infused intravenously during episodes of postoperative pulmonary hypertension. Methods and Results. During cardiac catheterization in 28 children, the effect of ATP-MgCl2 on the pulmonary artery pressure (PAP) and pulmonary vascular resistance index (R(p)) was compared with tolazoline. ATP-MgCl2 (0.1 mg of ATP per kilogram per minute) decreased mean PAP by 24% (P