Clinical profile and relevance of asymptomatic electrocardiography changes in lowlanders in high-altitude area

Abstract

ABSTRACT Aim: The aim of this study was to study the significance of electrocardiography (ECG) changes in healthy lowlanders during ascent to high altitude (HA) and analyze the changes along with cardiac risk scores. Materials and Methods: An observational study was carried out in a tertiary center of North-East India over 9 months among individuals who were evacuated due to ECG abnormalities on ascent to higher altitudes. All subjects underwent a standardized cardiac evaluation to assess the significance of the changes. Results: Forty-six male subjects who were evacuated from HA were included and evaluated for cardiac disease in a phased manner. The subjects (n = 21), whose ECG reverted to normal on descent, had a normal cardiac evaluation. However, in subjects with persistent changes after descent (n = 25), four (16%) had an abnormal treadmill test, one (4%) had an abnormal echocardiography, and one (4%) had significant disease on angiography. Conclusions: ECG changes are common in individuals ascending to HA. While some ECG changes may be sinister and mandate investigations, most spontaneously revert to normal on descent and may not indicate clinically significant situations. It is important to note that risk scores are crucial for assessing the risk of heart disease. Analyzing ECG changes along with risk profiles may be useful in the interpretation of the ECG.