High Altitude Climbing Increases Risk of Cardiac Arrhythmia, reveals JAMA study

However, the incidence and characteristics of arrhythmias in individuals undertaking extreme altitude climbs like Mount Everest remain understudied. A recent study was published in the journal JAMA Cardiology. The study was conducted by Sherpa K. and colleagues. This prospective cohort study aimed to explore the incidence of tachyarrhythmias and bradyarrhythmias in healthy individuals during a high-altitude expedition to Mount Everest.

Healthy individuals participating in the expedition underwent baseline cardiac evaluations, including electrocardiogram and echocardiography, before ascending Mount Everest. Ambulatory rhythm recording was conducted both before and during the climb. The primary outcome was the incidence of a composite of supraventricular and ventricular tachyarrhythmias, as well as bradyarrhythmias.

The key findings of the study were:

• 41 male individuals, with a mean age of 33.6 years, participated in the study.

• 38.2% of participants experienced cardiac arrhythmias during the climb, with 45 primary endpoint-relevant events recorded.

• Bradyarrhythmic events were more common, with 43 events documented in 13 individuals, compared to 2 ventricular tachycardias in 2 individuals.

• Arrhythmias occurred more frequently at lower altitudes without supplemental oxygen, with 80% of events occurring in this setting.

• The proportion of individuals with arrhythmias remained stable across altitudes, while event rates numerically increased between 5300 m and 7300 m before decreasing again at higher altitudes.

The study confirms a significant association between high-altitude exposure and the incidence of cardiac arrhythmias, with over one-third of healthy climbers experiencing arrhythmias during the ascent of Mount Everest. These findings underscore the importance of further research to explore the implications and management of cardiac rhythm disturbances in extreme altitude environments.

Understanding the prevalence and characteristics of cardiac arrhythmias in high-altitude climbers can inform risk assessment and management strategies for individuals undertaking similar expeditions. Additionally, these findings emphasize the need for medical interventions and monitoring to mitigate the risks associated with cardiac arrhythmias during high-altitude climbs.

Reference:

Sherpa, K., Sherpa, P. P., Sherpa, T., Rothenbühler, M., Ryffel, C., Sherpa, D., Sherpa, D. R., Sherchand, O., Galuszka, O., Dernektsi, C., Reichlin, T., & Pilgrim, T. (2024). Risk of cardiac arrhythmias among climbers on Mount Everest. JAMA Cardiology. https://doi.org/10.1001/jamacardio.2024.0364