Low Cardiac Output Augmentation during Exercise Stress Echocardiography at Low Altitude Predicts High Risk of Acute Mountain Sickness.

Objective: Stress-induced changes in echocardiographic parameters reflect cardiac reserve function. This study aimed to identify predictors of acute mountain sickness (AMS) using exercise stress echocardiography (ESE) before ascent. Methods: In this prospective cohort study, 104 healthy adults were enrolled and treated using ESE using a mechanically braked bicycle ergometer at a low altitude (LA) (500 m). Physiological data and echocardiographic parameters were collected before and during exercise. An ascent from 500 m to 4,100 m was completed by the bus within two days. AMS was identified using the Lake Louise Questionnaire. Participants with the lowest CO change rate after ESE presented the highest AMS risk. Conclusion: ESE could serve as an effective screening tool for AMS susceptibility, and blunted CO augmentation during exercise is an independent predictive marker for AMS risk.