Electrocardiographic Evidence for Right Heart Strain in Asymptomatic Children Living in Tibet—A Comparative Study Between Han Chinese and Ethnic Tibetans

ObjectiveTo compare ethnic Tibetan children with Han Chinese migrants for signs of right ventricular strain using electrocardiography (ECG) that would suggest chronic hypoxia at altitudes of 3500 to 4500 m above sea level.MethodsOne hundred thirty-five asymptomatic school children aged 7 to 12 years were assessed for height, weight, and blood pressure and underwent a single ECG at 2 centers at 3500 and 4500 m. A questionnaire was given to parents to provide demographic data with relevant medical history.ResultsThere was a high prevalence of right ventricular strain on ECG for both Tibetan and Han children (33%) with no significant difference between the 2 ethnic groups or sexes.ConclusionsOther studies showing higher observed rates of symptomatic chronic altitude sickness in Han Chinese children suggest that other extracardiologic factors play a role in the pathogenesis of the disease. To compare ethnic Tibetan children with Han Chinese migrants for signs of right ventricular strain using electrocardiography (ECG) that would suggest chronic hypoxia at altitudes of 3500 to 4500 m above sea level. One hundred thirty-five asymptomatic school children aged 7 to 12 years were assessed for height, weight, and blood pressure and underwent a single ECG at 2 centers at 3500 and 4500 m. A questionnaire was given to parents to provide demographic data with relevant medical history. There was a high prevalence of right ventricular strain on ECG for both Tibetan and Han children (33%) with no significant difference between the 2 ethnic groups or sexes. Other studies showing higher observed rates of symptomatic chronic altitude sickness in Han Chinese children suggest that other extracardiologic factors play a role in the pathogenesis of the disease.