Plasma endothelin concentrations in patients with pulmonary hypertension associated with congenital heart defects. Evidence for increased production of endothelin in pulmonary circulation.

Abstract

BACKGROUNDTo elucidate the pathophysiological significance of endothelin in pulmonary hypertension associated with congenital heart defects, we measured plasma endothelin-like immunoreactivity (ET-LI) concentrations by using radioimmunoassay in 18 patients with pulmonary hypertension (PH group; age, 6 months to 12 years) in comparison with 27 patients without pulmonary hypertension (non-PH group; age, 6 months to 12 years).METHODS AND RESULTSBlood samples were obtained from the vena cava, right atrium, right ventricle, left or right pulmonary artery, and pulmonary vein or the pulmonary arterial wedge position (pulmonary venous blood) during cardiac catheterization. Plasma ET-LI concentrations in the PH group were significantly higher than those in the non-PH group at all sampling sites. In the PH group, plasma ET-LI concentration showed a significant increase between the right ventricle and pulmonary artery and between the pulmonary artery and pulmonary vein. The increment of plasma ET-LI concentrations f...