[Comparison of echocardiographic parameters in healthy Chinese children born and living at high altitude or at sea-level].

Objective: Chronic hypoxia at high altitude might result in cardiopulmonary adaptations including pulmonary arterial hypertension and cardiac remodeling. But little is known about the adaptive changes in healthy children born and living at high altitude. We compared the echocardiographic measurements between the healthy children living at 16 m (Shanghai, n = 220) and 3 700 m (Qinghai, total 257, Han children 117, Tibetan children 140).

Methods: Children's age ranged from 15 d to 14 years. Echocardiography measurements were performed, values of the left and right ventricular dimensions and wall thickness, systolic and diastolic function including cardiac output index (CI), as well as mean pulmonary arterial pressure (mPAP) were obtained.

Results: mPAP and right heart dimension, CI, right ventricular anterior wall thickness were significantly higher while ventricular systolic and diastolic function were significantly lower in 3 700 m group than in 16 m group (all P < 0.05). Left ventricular dimension was similar between the two groups. There were no differences on above measured parameters between the Han and Tibetan children from 3 700 m group (all P > 0.05).

Conclusions: Children born and living at high altitude in China have significantly higher mPAP, dilated right heart and lower systolic and diastolic function of both ventricles and higher CI compared to children born and living at see-level. Above parameters were similar between the Han and the Tibetan childen born and living at high altitude. Present study provides reference values for the healthy children living at high altitude.