Right-heart response to short-term low oxygen in people with past HAPE

Effect of Acute Hypoxia on RIght VEntRicular Function. A Single-Center, Double-Blind, Randomized Controlled Cross-Over Trial.

Not applicable Interventional University of Zurich · NCT07431554

This trial tests whether brief exposure to simulated high altitude (low oxygen) changes right-heart function in adults who previously had high-altitude pulmonary edema (HAPE).

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment18 (estimated)
Ages18 Years to 80 Years
SexAll
SponsorUniversity of Zurich Academic / other
Locations1 site (Zurich)
Trial IDNCT07431554 on ClinicalTrials.gov

What this trial studies

Adults with past HAPE will be exposed, in random order, to three simulated oxygen levels corresponding roughly to 490 m, 2,500 m and 4,000 m both at rest and during light cycling exercise using a controlled gas mixture. The trial uses a randomized, double-blind, cross-over design so each participant experiences all conditions without knowing which is being simulated. Right ventricular function will be measured noninvasively with speckle-tracking echocardiography, and investigators will also record heart rate, blood pressure, blood gases, tissue oxygenation and symptoms such as shortness of breath. The study is single-center and focuses on acute (short-term) physiologic responses rather than long-term outcomes.

Who should consider this trial

Good fit: Adults aged 18–80 with confirmed or suspected past HAPE who live below 800 m and have not had recent exposure above 2,500 m within the prior three weeks are ideal candidates.

Not a fit: People with other diagnosed cardiopulmonary disease, pregnancy or lactation, permanent residence above 800 m, recent high-altitude exposure, or inability to complete study procedures are not eligible and are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, the results could help identify who with past HAPE is at risk for right-heart strain at altitude and inform safer guidance for mountain activities.

How similar studies have performed: Previous research has shown acute right-ventricular changes during simulated hypoxia and used speckle-tracking echocardiography, but applying these methods specifically to people with past HAPE is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Signed informed consent
* Diagnosed or suspicion of past HAPE
* 18-80 years (age group young: 18-39.99 years / age group older: 40-80 years)
* All sex and genders
* Living \<800m and without altitude exposure \> 2500 m and \> 24h within the last three weeks

Exclusion Criteria:

* \<18, \>80 years old
* Any other diagnosed cardiopulmonary condition
* Other clinically significant severe concomitant disease states (e.g. renal, hepatic dysfunction, etc.)
* Inability to follow the procedures of the study due to language problems, psychological neurological disorders or orthopaedic disorders
* Participants permanently living \>800m and altitude exposure \> 2500 m and \>24h within the last three weeks
* Pregnancy: Participants will be asked if pregnant or not, no screening for undetected pregnancy
* Lactating women
* Participation in other study with active treatment

Where this trial is running

Zurich

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Altitude HypoxiaHypoxiaNormobaric HypoxiaRight Ventricular Functionright ventricular free wall strainRVFWSright ventricular functiontissue oxygenation
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.