Bosentan decreases pulmonary vascular resistance and improves exercise capacity in acute hypoxia.

Background: Altitude exposure is associated with mild pulmonary hypertension and decreased exercise capacity. We tested the hypothesis that pulmonary vascular resistance (PVR) contributes to decreased exercise capacity in hypoxic healthy subjects.

Methods: An incremental cycle ergometer cardiopulmonary exercise test and echocardiographic estimation of pulmonary artery pressure (Ppa) and cardiac output to calculate total PVR were performed in 11 healthy volunteers in normoxia and after 1 h of hypoxic breathing (12% O(2)).