Volume 19: Issue 3

The current understanding of high-altitude pulmonary hypertension (HAPH) is largely attributable to the work of a small cadre of international scientists. The present article discusses the discovery and early investigations into HAPH that now serve as the foundation of our modern understanding of the disease. Further, though HAPH is clearly a distinct entity, we highlight how this early work led to a broader understanding of pulmonary vascular disease—including pulmonary arterial hypertension (PAH)—through the development of translational clinical models of disease, elucidation of hypoxic signaling, and therapeutics applicable to PAH.

Conveniences of modern travel allow for an increasing number of people to sojourn to mountainous, high-altitude locations for work and/or pleasure. Travel to these types of locations places unique stressors on the human body and, more specifically, the cardiovascular and pulmonary systems since ambient oxygen content declines at altitude. The physiologic response to hypoxia is a highly dynamic process that begins immediately and continues to evolve from acute (hours to days) to chronic (days to weeks) time periods. Furthermore, sojourns to hypoxic locations frequently involve exercise, which places additional strain on the heart and lungs. The aim of this review is to emphasize clinically relevant physiologic responses that occur, both acutely and chronically, after travel to high-altitude locations.

WHAT HAPPENS AT HIGH ALTITUDE?

High altitude is defined in the literature^1,2 as locations higher than 2500 m (8000 feet) above sea level. Increased altitude leads to lower barometric pressures, lower partial pressure, and lower inspired oxygen levels, leading to hypoxia. The body's attempt at homeostasis triggers increased ventilation, vasoconstriction of the pulmonary vasculature, systemic vasodilation, as well as increased heart rate, blood pressure, cardiac output, and hemoglobin. Importantly, pulmonary arterial pressures increase along with pulmonary vascular resistance at high altitudes. These effects are profound in patients with baseline pulmonary hypertension, as exposure to high altitudes

Full Issue PDF

From the Andes to the Rocky Mountains: A Historical View of High-Altitude Pulmonary Hypertension

Impact of Altitude on Cardiopulmonary and Right Ventricular Hemodynamics During Exercise

PH Professional Network: Up, Up, and Away: Clinical Considerations for Altitude-Related Travel and Pulmonary Hypertension

WHAT HAPPENS AT HIGH ALTITUDE?

A Life at High Altitude: A Conversation With Todd Bull and Peter Hackett

Editor’s Memo

Guest Editor’s Memo

Conference Abstracts

Guest Editor’s Memo

A Roundtable Discussion Addressing Patient-Centered Care and Quality of Life in Patients With Pulmonary Arterial Hypertension

Editor’s Memo

Pulmonary Hypertension Associated With Parenchymal Lung Disease