How the Right Side of the Heart Reacts to Short-Term Low Oxygen Levels at Rest and During Light Exercise in Adults with Past HAPE

What this Trial Is About

Researchers are investigating how the heart, especially the right ventricle, reacts to low oxygen levels during short-term exposure to simulated altitudes of 2,500 m and 4,000 m. This study focuses on adults with a history of high-altitude pulmonary edema HAPE and aims to understand how right ventricular function changes under these conditions, both at rest and during light exercise. The study uses a randomized, double-blind, cross-over design to explore these effects and improve future support for affected patients. Participants will experience three different simulated altitude conditions near sea level 490 m, 2,500 m, and 4,000 m above sea level. Each participant breathes a special gas mixture that mimics these altitudes while resting and during low-intensity cycling exercise. The order of these conditions is randomized, with at least a two-hour break between exposures to allow recovery. The study measures heart function using ultrasound and other vital signs throughout each condition. During each study visit, participants undergo a one-hour resting period followed by a 10-minute cycling exercise at low intensity. Researchers measure heart rate, blood pressure, oxygen saturation, lung and brain oxygen levels, and symptoms such as breathlessness and leg fatigue. Blood samples are taken to analyze various markers. The main outcome is how the right ventricle functions during rest and exercise under low oxygen. Participation may last two to three days, scheduled flexibly for each individual.

Effect of Acute Hypoxia on RIght VEntRicular Function in HAPE.