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Updated: Aug 8, 2026
08:19
Electrophysiological Assessment of Murine Atria with High-Resolution Optical Mapping
Published on: February 22, 2018
Age, altitude, and arrhythmia
1Department of Veterans Affairs Medical Center, Houston, Texas 77030, USA.
Texas Heart Institute Journal
|January 1, 1995
Summary
High altitude climbing triggered significant heart rhythm changes, including ventricular bigeminy, in an older man. These arrhythmias resolved with reduced exertion, highlighting exercise and hypoxia effects on cardiac electrophysiology.
Area of Science:
- Cardiology
- Altitude Physiology
- Exercise Science
Background:
- Assessing cardiac electrophysiological responses to extreme altitude and exercise in older adults.
- Investigating the impact of hypoxia on cardiac rhythm in individuals without pre-existing heart conditions.
Observation:
- Continuous Holter monitoring during a 5,895m ascent in a 65-year-old male.
- Documenting significant ventricular ectopy and left ventricular bigeminy during ascent.
- Noting increased P-wave amplitude in lead V2 with an unchanged QT interval.
Findings:
- Development of marked ventricular ectopy and left ventricular bigeminy during ascent.
- Resolution of bigeminy upon descent, with persistent increased premature ventricular complexes.
- Correlation of arrhythmias with increased aerobic stress under hypoxic conditions.
Implications:
- Hypoxia and prolonged exercise can activate arrhythmogenic mechanisms, particularly in older individuals.
- Age-related susceptibility to exercise- and hypoxia-induced arrhythmias warrants further investigation.
- Understanding these mechanisms is crucial for managing cardiac health during high-altitude activities.
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