Stuber Thomas, Sartori Claudio, Salmòn Carlos Salinas, Hutter Damian, Thalmann Sébastien, Turini Pierre, Jayet Pierre-Yves, Schwab Marcos, Sartori-Cucchia Céline, Villena Mercedes, Scherrer Urs, Allemann Yves
Swiss Cardiovascular Center Bern, University Hospital, Bern, Switzerland.
Department of Internal Medicine and Botnar Center for Extreme Medicine, University Hospital, Lausanne, Switzerland.
Chest. 2008 Nov;134(5):996-1000. doi: 10.1378/chest.08-0854. Epub 2008 Jul 18.
Invasive studies suggest that healthy children living at high altitude display pulmonary hypertension, but the data to support this assumption are sparse. Nitric oxide (NO) synthesized by the respiratory epithelium regulates pulmonary artery pressure, and its synthesis was reported to be increased in Aymara high-altitude dwellers. We hypothesized that pulmonary artery pressure will be lower in Aymara children than in children of European ancestry at high altitude, and that this will be related to increased respiratory NO. We therefore compared pulmonary artery pressure and exhaled NO (a marker of respiratory epithelial NO synthesis) between large groups of healthy children of Aymara (n = 200; mean +/- SD age, 9.5 +/- 3.6 years) and European ancestry (n = 77) living at high altitude (3,600 to 4,000 m). We also studied a group of European children (n = 29) living at low altitude. The systolic right ventricular to right atrial pressure gradient in the Aymara children was normal, even though significantly higher than the gradient measured in European children at low altitude (22.5 +/- 6.1 mm Hg vs 17.7 +/- 3.1 mm Hg, p < 0.001). In children of European ancestry studied at high altitude, the pressure gradient was 33% higher than in the Aymara children (30.0 +/- 5.3 mm Hg vs 22.5 +/- 6.1 mm Hg, p < 0.0001). In contrast to what was expected, exhaled NO tended to be lower in Aymara children than in European children living at the same altitude (12.4 +/- 8.8 parts per billion [ppb] vs 16.1 +/- 11.1 ppb, p = 0.06) and was not related to pulmonary artery pressure in either group. Aymara children are protected from hypoxic pulmonary hypertension at high altitude. This protection does not appear to be related to increased respiratory NO synthesis.
侵入性研究表明，生活在高海拔地区的健康儿童会出现肺动脉高压，但支持这一假设的数据很少。呼吸道上皮合成的一氧化氮（NO）可调节肺动脉压力，据报道，艾马拉族高海拔居民体内的NO合成增加。我们假设，在高海拔地区，艾马拉族儿童的肺动脉压力会低于欧洲血统儿童，且这与呼吸道NO增加有关。因此，我们比较了一大群生活在高海拔地区（3600至4000米）的健康艾马拉族儿童（n = 200；平均±标准差年龄，9.5±3.6岁）和欧洲血统儿童（n = 77）的肺动脉压力和呼出NO（呼吸道上皮NO合成的标志物）。我们还研究了一组生活在低海拔地区的欧洲儿童（n = 29）。艾马拉族儿童的收缩期右心室与右心房压力梯度正常，尽管明显高于低海拔地区欧洲儿童测得的梯度（22.5±6.1毫米汞柱对17.7±3.1毫米汞柱，p < 0.001）。在高海拔地区研究的欧洲血统儿童中，压力梯度比艾马拉族儿童高33%（30.0±5.3毫米汞柱对22.5±6.1毫米汞柱，p < 0.0001）。与预期相反，艾马拉族儿童呼出的NO往往低于生活在同一海拔的欧洲儿童（12.4±8.8十亿分之一[ppb]对16.1±11.1 ppb，p = 0.06），且在两组中均与肺动脉压力无关。艾马拉族儿童在高海拔地区可免受缺氧性肺动脉高压的影响。这种保护作用似乎与呼吸道NO合成增加无关。
