Supine bicycle stress echocardiography at low altitude for identification of susceptibility to acute mountain sickness

Yi Wang; Qingfeng Zhang; Kai Wang; Sijia Wang; Yong Jing; Shiyin Chen; Lan Shang; Chunmei Li; Yan Deng; Yun Xu; Lixue Yin

doi:10.1016/j.echo.2024.12.007

Supine bicycle stress echocardiography at low altitude for identification of susceptibility to acute mountain sickness

J Am Soc Echocardiogr. 2024 Dec 15:S0894-7317(24)00637-0. doi: 10.1016/j.echo.2024.12.007. Online ahead of print.

Authors

Yi Wang¹, Qingfeng Zhang², Kai Wang³, Sijia Wang¹, Yong Jing¹, Shiyin Chen⁴, Lan Shang⁵, Chunmei Li¹, Yan Deng¹, Yun Xu¹, Lixue Yin⁶

Affiliations

¹ Key Laboratory of Ultrasound in Cardiac Electrophysiology and Biomechanics of Sichuan Province, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
² School of Medicine, University of Electronic Science and Technology of China, Chengdu, China; Key Laboratory of Ultrasound in Cardiac Electrophysiology and Biomechanics of Sichuan Province, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
³ Department of Acute Care Surgery, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
⁴ Department of Chinese medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China.
⁵ Department of Radiology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
⁶ Key Laboratory of Ultrasound in Cardiac Electrophysiology and Biomechanics of Sichuan Province, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China. Electronic address: yinlixue_cardiac@163.com.

PMID: 39689841
DOI: 10.1016/j.echo.2024.12.007

Abstract

Background: Exposure to high altitude may unpredictably lead to acute mountain sickness (AMS). The purpose of this study was to identify the predictors of AMS at low altitude by exercise stress echocardiography (ESE).

Methods: A total of 40 healthy adults were enrolled and underwent comprehensive supine bicycle ESE at low altitude, including pulmonary vascular resistance (PVR), right ventricular (RV) area index at the end of diastole (RVEDAi), B-lines, and inferior vena cava (IVC) diameter. All subjects ascended to 3600m within 24 hours. The risk factors for AMS were screened by least absolute shrinkage and selection operator (LASSO) regression analysis. A novel nomogram model was then established by multivariable logistic regression analysis and Clinical Impact Curve (CIC) was constructed.

Results: At the altitude of 3600 m, 20 of 40 subjects had AMS (AMS group). Through LASSO regression analyses, PVR, IVC and B-lines at peak exercise were all independent influencing factors for AMS. The nomogram built on the basis of these factors predicted AMS with sensitivity of 0.950, specificity of 0.804, which outperformed the individual predictive C-indexes of each indicator (nomogram: cutoff, 59.3, AUC, 0.90 (95% CI, 0.80-1.00), PVR-peak: cutoff, 1.55, AUC, 0.81 (95% CI, 0.70-0.91), B line-peak: cutoff, 1, AUC, 0.78 (95% CI, 0.69-0.92), IVC-peak: cutoff, 13.8, AUC, 0.74 (95% CI, 0.65-0.87)). The established model was validated by plotting the clinical decision curve analysis (DCA) and clinical impact curve (CIC).

Conclusions: Supine bicycle ESE is a useful technique to identify subjects susceptible to AMS. We established a nomogram to predict the development to AMS with high discrimination and accuracy.

Keywords: acute mountain sickness; pulmonary artery pressure; pulmonary vascular resistance; right ventricular function; stress echocardiography.