Exaggerated hypoxia-induced pulmonary hypertension is a hallmark of high-altitude pulmonary edema (HAPE) and plays a major role in its pathogenesis. Many studies of HAPE have estimated systolic pulmonary arterial pressure (SPAP) with Doppler echocardiography. Whereas at low altitude, Doppler echocardiographic estimation of SPAP correlates closely with its invasive measurement, no such evidence ...