Relevance of Asymptomatic Electrocardiographic Abnormalities at High Altitude.

Background Cardiovascular diseases, especially coronary artery disease, are epidemic in India. However there is paucity of data regarding coronary artery disease in high altitude. This study was conducted to determine the importance of asymptomatic ECG abnormalities in high altitude with relevance to coronary artery disease. Method A total of 54 subjects were included in the study. All of them underwent acclimatization before ascent to high altitude. Subjects were selected if they were detected to have ECG abnormality in high altitude. Various parameters such as height, weight, BMI, and multiple laboratory parameters were also recorded. Results Out of 54 subjects, mean age was 40.6 yrs. Mean BMI was 24.28 Kg/ m2. Most common ECG abnormality was T wave inversion in inferiorly directed frontal plane leads seen in 16 (29.6%) subjects followed by T wave inversion in both inferiorly directed frontal plane leads and precordial leads noted in 13 (24%) subjects. Next most common ECG abnormality was T wave inversion in the precordial leads seen in 10 (18.5%) subjects. Only three subjects turned out to be positive for inducible ischemia. Coronary angiography however showed normal coronaries in all the three subjects. Conclusions Our study suggests that majority of ECG abnormalities in high altitude are transient/ benign in nature and do not suggest an increased risk of cardiovascular disease whether evaluated by Framingham Risk Score or structural/ functional evaluation by 2D Echocardiography/ Treadmill Test.