Nitric oxide and prostacyclin treatment of an infant with primary pulmonary hypertension

Abstract

Primary pulmonary hypertension is a progressive disease with high mortality. The etiology of primary pulmonary hypertension in pediatric patients is unknown; some cases are thought to be familial, 1 but most are sporadic. Mortality is high if the disease is present in infants < 2 years of age 2,3 Younger children with primary pulmonary hypertension have a larger decrease in pulmonary vascular resistance (PVR) with vasodilators than older patients, suggesting vasoconstriction is more important than structural changes in the development of pediatric primary pulmonary hypertension. 4 Therefore, vasodilator therapy may be more successful in younger patients because of increased pulmonary vasoreactivity. Prostacyclin is often effective as an acute vasodilator in pediatric primary pulmonary hypertension. 4 Therapy with prostacyclin and other vasodilators is frequently limited because of systemic hypotension. Brief inhalation of nitric oxide selectively dilates the pulmonary vascular bed of adults with primary pulmonary hypertension 5 and children with primary pulmonary hypertension 6 and congenital heart disease, 7,8 but has not been used as prolonged therapy without assisted ventilation. We describe a case of primary pulmonary hypertension in which inhalation of nitric oxide successfully aided the transition to chronic prostacyclin infusion (therapy with oxygen and calcium antagonists was not effective and prostacyclin was not immediately available).