Publication
Title
Pulmonary artery pressure limits exercise capacity at high altitude
Author
Abstract
Altitude exposure is associated with decreased exercise capacity and increased pulmonary vascular resistance (PVR). Echocardiographic measurements of pulmonary haemodynamics and a cardiopulmonary exercise test were performed in 13 healthy subjects at sea level, in normoxia and during acute hypoxic breathing (1 h, 12% oxygen in nitrogen), and in 22 healthy subjects after acclimatisation to an altitude of 5,050 m. The measurements were obtained after randomisation, double-blinded to the intake of placebo or the endothelin A receptor blocker sitaxsentan (100 mg.day(-1) for 7 days). Blood and urine were sampled for renal function measurements. Normobaric as well as hypobaric hypoxia increased PVR and decreased maximum workload and oxygen uptake (V'O(2),max). Sitaxsentan decreased PVR in acute and chronic hypoxia (both p<0.001), and partly restored V'O(2)max, by 30 % in acute hypoxia (p<0.001) and 10% in chronic hypoxia (p<0.05). Sitaxsentan-induced changes in PVR and V'O(2),max were correlated (p=0.01). Hypoxia decreased glomerular filtration rate and free water clearance, and increased fractional sodium excretion. These indices of renal function were unaffected by sitaxsentan intake. Selective endothelin A receptor blockade with sitaxsentan improves mild pulmonary hypertension and restores exercise capacity without adverse effects on renal function in hypoxic normal subjects.
Language
English
Source (journal)
The European respiratory journal. - Copenhagen
Publication
Copenhagen : 2010
ISSN
0903-1936
Volume/pages
36:5(2010), p. 1049-1055
ISI
000283669700014
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 06.01.2015
Last edited 19.06.2017