Risk of Cardiac Arrhythmias Among Climbers on Mount Everest.
Options
BORIS DOI
Publisher DOI
PubMed ID
38568602
Description
IMPORTANCE
Arterial hypoxemia, electrolyte imbalances, and periodic breathing increase the vulnerability to cardiac arrhythmia at altitude.
OBJECTIVE
To explore the incidence of tachyarrhythmias and bradyarrhythmias in healthy individuals at high altitudes.
DESIGN, SETTING, AND PARTICIPANTS
This prospective cohort study involved healthy individuals at altitude (8849 m) on Mount Everest, Nepal. Recruitment occurred from January 25 to May 9, 2023, and data analysis took place from June to July 2023.
EXPOSURE
All study participants underwent 12-lead electrocardiogram, transthoracic echocardiography, and exercise stress testing before and ambulatory rhythm recording both before and during the expedition.
MAIN OUTCOME
The incidence of a composite of supraventricular (>30 seconds) and ventricular (>3 beats) tachyarrhythmia and bradyarrhythmia (sinoatrial arrest, second- or third-degree atrioventricular block).
RESULTS
Of the 41 individuals recruited, 100% were male, and the mean (SD) age was 33.6 (8.9) years. On baseline investigations, there were no signs of exertional ischemia, wall motion abnormality, or cardiac arrhythmia in any of the participants. Among 34 individuals reaching basecamp at 5300 m, 32 participants climbed to 7900 m or higher, and 14 reached the summit of Mount Everest. A total of 45 primary end point-relevant events were recorded in 13 individuals (38.2%). Forty-three bradyarrhythmic events were documented in 13 individuals (38.2%) and 2 ventricular tachycardias in 2 individuals (5.9%). Nine arrhythmias (20%) in 5 participants occurred when climbers were using supplemental bottled oxygen, whereas 36 events (80%) in 11 participants occurred at lower altitudes when no supplemental bottled oxygen was used. The proportion of individuals with arrhythmia remained stable across levels of increasing altitude, while event rates per 24 hours numerically increased between 5300 m (0.16 per 24 hours) and 7300 m (0.37 per 24 hours) before decreasing again at higher altitudes, where supplemental oxygen was used. None of the study participants reported dizziness or syncope.
CONCLUSION AND RELEVANCE
In this study, more than 1 in 3 healthy individuals experienced cardiac arrhythmia during the climb of Mount Everest, thereby confirming the association between exposure to high altitude and incidence of cardiac arrhythmia. Future studies should explore the potential implications of these rhythm disturbances.
Arterial hypoxemia, electrolyte imbalances, and periodic breathing increase the vulnerability to cardiac arrhythmia at altitude.
OBJECTIVE
To explore the incidence of tachyarrhythmias and bradyarrhythmias in healthy individuals at high altitudes.
DESIGN, SETTING, AND PARTICIPANTS
This prospective cohort study involved healthy individuals at altitude (8849 m) on Mount Everest, Nepal. Recruitment occurred from January 25 to May 9, 2023, and data analysis took place from June to July 2023.
EXPOSURE
All study participants underwent 12-lead electrocardiogram, transthoracic echocardiography, and exercise stress testing before and ambulatory rhythm recording both before and during the expedition.
MAIN OUTCOME
The incidence of a composite of supraventricular (>30 seconds) and ventricular (>3 beats) tachyarrhythmia and bradyarrhythmia (sinoatrial arrest, second- or third-degree atrioventricular block).
RESULTS
Of the 41 individuals recruited, 100% were male, and the mean (SD) age was 33.6 (8.9) years. On baseline investigations, there were no signs of exertional ischemia, wall motion abnormality, or cardiac arrhythmia in any of the participants. Among 34 individuals reaching basecamp at 5300 m, 32 participants climbed to 7900 m or higher, and 14 reached the summit of Mount Everest. A total of 45 primary end point-relevant events were recorded in 13 individuals (38.2%). Forty-three bradyarrhythmic events were documented in 13 individuals (38.2%) and 2 ventricular tachycardias in 2 individuals (5.9%). Nine arrhythmias (20%) in 5 participants occurred when climbers were using supplemental bottled oxygen, whereas 36 events (80%) in 11 participants occurred at lower altitudes when no supplemental bottled oxygen was used. The proportion of individuals with arrhythmia remained stable across levels of increasing altitude, while event rates per 24 hours numerically increased between 5300 m (0.16 per 24 hours) and 7300 m (0.37 per 24 hours) before decreasing again at higher altitudes, where supplemental oxygen was used. None of the study participants reported dizziness or syncope.
CONCLUSION AND RELEVANCE
In this study, more than 1 in 3 healthy individuals experienced cardiac arrhythmia during the climb of Mount Everest, thereby confirming the association between exposure to high altitude and incidence of cardiac arrhythmia. Future studies should explore the potential implications of these rhythm disturbances.
Date of Publication
2024-05-01
Publication Type
Article
Subject(s)
Language(s)
en
Contributor(s)
Sherpa, Kunjang | |
Sherpa, Pasang Phurba | |
Sherpa, Tendi | |
Sherpa, Dhukpa | |
Sherpa, Dawa Renji | |
Sherchand, Ojaswee |
Additional Credits
Series
JAMA cardiology
Publisher
American Medical Association
ISSN
2380-6583
Access(Rights)
restricted