OBJECTIVE: Pregnancy at high altitude has been associated with increased prevalence of pre-eclampsia and reduced maternal oestrogen levels, factors that have been associated with endothelial dysfunction. The aim of this study was to examine the effect of high altitude (4370 m above sea level) on endothelial function during pregnancy as assessed by a non-invasive method. DESIGN: Cross-sectional study. SETTING: Two maternity units providing routine antenatal care: one at high altitude (District General Hospital--IPSS in Cerro de Pasco, Peru) and one at sea level (Instituto Materno-Perinatal in Lima, Peru). POPULATION: Sixty pregnant women at 6-42 weeks of gestation resident at high altitude (Cerro de Pasco, Peru, 4370 m above sea level) and 54 at sea level (Lima, Peru). Comparisons were performed also in 11 and 14 non-pregnant women at each altitude, respectively. METHODS: Endothelial function was assessed by flow-mediated dilatation of the brachial artery using high-resolution ultrasound. MAIN OUTCOME MEASURES: Differences in flow mediated dilatation of the brachial artery in two groups of pregnant women, one at high altitude and one at sea level. RESULTS: Both at high altitude and sea level flow-mediated dilatation of the brachial artery increased in the first two trimesters to levels 32% higher than non-pregnant controls. However, in the third trimester, flow-mediated dilatation of the brachial artery was lower than non-pregnant levels. Resting vessel size increased during pregnancy by 15% compared with non-pregnant controls at term, with no difference between the two populations at high and low altitude. Pregnancy at high altitude, compared with sea level, was associated with 59% lower baseline blood flow and 76% higher reactive hyperaemia. Similarly, non-pregnant controls at high altitude compared with sea level demonstrated similar flow-mediated dilatation of the brachial artery and 40% lower resting blood flow of the brachial artery. However, the difference in reactive hyperaemia did not reach statistical significance. CONCLUSION: These data suggest that, during pregnancy at high altitude, endothelial function, as assessed by flow-mediated dilatation of the brachial artery, is not impaired.
OBJECTIVE: Pregnancy at high altitude has been associated with increased prevalence of pre-eclampsia and reduced maternal oestrogen levels, factors that have been associated with endothelial dysfunction. The aim of this study was to examine the effect of high altitude (4370 m above sea level) on endothelial function during pregnancy as assessed by a non-invasive method. DESIGN: Cross-sectional study. SETTING: Two maternity units providing routine antenatal care: one at high altitude (District General Hospital--IPSS in Cerro de Pasco, Peru) and one at sea level (Instituto Materno-Perinatal in Lima, Peru). POPULATION: Sixty pregnant women at 6-42 weeks of gestation resident at high altitude (Cerro de Pasco, Peru, 4370 m above sea level) and 54 at sea level (Lima, Peru). Comparisons were performed also in 11 and 14 non-pregnant women at each altitude, respectively. METHODS: Endothelial function was assessed by flow-mediated dilatation of the brachial artery using high-resolution ultrasound. MAIN OUTCOME MEASURES: Differences in flow mediated dilatation of the brachial artery in two groups of pregnant women, one at high altitude and one at sea level. RESULTS: Both at high altitude and sea level flow-mediated dilatation of the brachial artery increased in the first two trimesters to levels 32% higher than non-pregnant controls. However, in the third trimester, flow-mediated dilatation of the brachial artery was lower than non-pregnant levels. Resting vessel size increased during pregnancy by 15% compared with non-pregnant controls at term, with no difference between the two populations at high and low altitude. Pregnancy at high altitude, compared with sea level, was associated with 59% lower baseline blood flow and 76% higher reactive hyperaemia. Similarly, non-pregnant controls at high altitude compared with sea level demonstrated similar flow-mediated dilatation of the brachial artery and 40% lower resting blood flow of the brachial artery. However, the difference in reactive hyperaemia did not reach statistical significance. CONCLUSION: These data suggest that, during pregnancy at high altitude, endothelial function, as assessed by flow-mediated dilatation of the brachial artery, is not impaired.
Authors: Patrick F McArdle; Brian W Whitcomb; Keith Tanner; Braxton D Mitchell; Alan R Shuldiner; Afshin Parsa Journal: BMC Cardiovasc Disord Date: 2012-03-14 Impact factor: 2.298
Authors: E G Mulder; S de Haas; Z Mohseni; N Schartmann; F Abo Hasson; F Alsadah; Smj van Kuijk; J van Drongelen; Mea Spaanderman; C Ghossein-Doha Journal: BJOG Date: 2021-04-06 Impact factor: 7.331