Markers of cardiovascular risk and their reversibility with acute oxygen therapy in Kyrgyz highlanders with high altitude pulmonary hypertension

Background: High altitude pulmonary hypertension (HAPH), a chronic altitude related illness, is associated with hypoxemia, dyspnea and reduced exercise performance. We evaluated ECG and pulse wave-derived markers of cardiovascular risk in highlanders with HAPH (HAPH+) in comparison to healthy highlanders (HH) and lowlanders (LL) and the effects of hyperoxia. Methods: We studied 34 HAPH+ and 54 HH at Aksay (3250 m), and 34 LL at Bishkek (760 m), Kyrgyzstan. Mean pulmonary artery pressure by echocardiography was mean ± SD 34 ± 3, 22 ± 5, 16 ± 4 mmHg, respectively (p