Association between high cardiac output at altitude and acute mountain sickness: preliminary study on Mt. Fuji

A preliminary study on Mt. Fuji reveals that individuals experiencing acute mountain sickness (AMS) exhibit significantly higher cardiac index (CI) and changes in CI compared to those without AMS at high altitudes. The research, involving 11 volunteers ascending from 2,380 m to the Mt. Fuji Research Station (MFRS) at 3,775 m, found that AMS subjects had a median CI of 4.9 mL/min/m² before sleeping and a ΔCI increase of 1.6 mL/min/m² compared to non-AMS subjects. Notably, ΔCI dropped significantly after sleeping in AMS individuals, suggesting an association between high cardiac output and the development of AMS. This study sheds light on the potential role of cardiovascular responses in altitude-related illness.

Ebihara, T., Shimizu, K., Mitsuyama, Y., Ogura, H., & Oda, J. (2023). Association between high cardiac output at altitude and acute mountain sickness: preliminary study on Mt. Fuji. Journal of Physiological Anthropology, 42(1). https://doi.org/10.1186/s40101-023-00322-7