Clinical Implications for Exercise at Altitude Among Individuals With Cardiovascular Disease

Abstract

An increasing number of individuals travel to mountainous environments for work and pleasure. However, oxygen availability declines at altitude, and hypoxic environments place unique stressors on the cardiovascular system. These stressors may be exacerbated by exercise at altitude, because exercise increases oxygen demand in an environment that is already relatively oxygen deplete compared with sea‐level conditions. Furthermore, the prevalence of cardiovascular disease, as well as diseases such as hypertension, heart failure, and lung disease, is high among individuals living in the United States. As such, patients who are at risk of or who have established cardiovascular disease may be at an increased risk of adverse events when sojourning to these mountainous locations. However, these risks may be minimized by appropriate pretravel assessments and planning through shared decision‐making between patients and their managing clinicians. This American Heart Association scientific statement provides a concise, yet comprehensive overview of the physiologic responses to exercise in hypoxic locations, as well as important considerations for minimizing the risk of adverse cardiovascular events during mountainous excursions.

Right Ventricular Response to Acute Hypoxia among Healthy Humans

“…Pulmonary arterial (PA) pressures and right ventricular (RV) afterload increase in response to hypoxia ( 1 ). Limited data are available that describe RV adaptations to acute hypoxia and the associated increases in afterload, occurring in response to clinical scenarios such as infections, pulmonary embolism, and hypoxia associated with high-altitude exposure ( 2 ).…”

“…Healthy adults free of cardiovascular, hematologic, and pulmonary disease underwent hemodynamic assessment. Individuals residing at ⩾2,500 m (8,000 ft) for three or more consecutive nights within 30 days of testing were excluded ( 2 ). Written informed consent was obtained.…”

Coronary Syndromes and High-Altitude Exposure—A Comprehensive Review

“…The Scientific Statement from the American Heart Association recommends a pretravel assessment for all patients with CAD. Further, pretravel exercise testing may be necessary [ 38 ]. If positive, further imaging testing is recommended.…”

Electrocardiographic Changes During Sustained Normobaric Hypoxia in Patients After Myocardial Infarction

“…Patients post myocardial infarction may be prone to ventricular arrhythmias depending on revascularization (2), concomitant pharmacotherapy, left ventricular impairment, and myocardial scaring. Normobaric hypoxia, which simulates high altitude, reproduces high-altitude PH (1,3).…”