Can a week at sea level ease strain on High-Altitude hearts?

NCT ID NCT07804693

What the study statuses mean

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Recruitment status, easiest to join first

Recruiting now
This trial is taking on new participants right now.
Not yet recruiting This study
Registered, but not yet taking participants.
By invitation only
Not open to general applications. Only people the study team invites can take part.
Paused
Paused for now. It may or may not start again.
Ongoing
Running, but no longer taking on new participants.
Completed
The trial has finished. Results may not be published yet.
Stopped early
Stopped early, before it reached the end. That can be for many reasons, including safety.
Cancelled
Cancelled before anyone took part.

Expanded access (not trials)

Expanded access
Not a trial. This treatment can be requested outside a study, case by case, for people who qualify.
Expanded access (paused)
Not a trial. The treatment can normally be requested outside a study, but is unavailable right now.
Expanded access (ended)
Not a trial. The treatment could once be requested outside a study, but no longer can.
Approved
The treatment has been approved, so it is available normally rather than through this programme.

When the status isn't known

Details not published
The full record has not been published yet, so there is little to show here.
Status unknown
This status has not been confirmed recently, so it may be out of date.

First seen Sep 04, 2026 · Last updated Sep 04, 2026

Summary

This trial studies people with pulmonary arterial hypertension (PAH) who live permanently above 2600 meters. Researchers want to see if spending one week at sea level and then returning to high altitude changes pressure in the lung's blood vessels. They will measure heart and lung function, exercise ability, blood oxygen, and sleep quality in patients and healthy controls. The goal is to understand whether a temporary descent could offer any benefit or risk for this group.

What this could mean

Our plain-language read of the trial. This is informational only, not medical advice or a prediction.

Active substance
A one-week stay at sea level followed by return to high altitude (2850m)
What this could lead to
If the descent eases strain on the heart and lungs, it could point toward periodic low-altitude stays as a supportive strategy for people with pulmonary arterial hypertension living at high altitude.
What could go wrong
This is a small, early study with 20 participants, so results may not apply to everyone. Re-ascending to high altitude could worsen symptoms or blood oxygen levels in some patients.

This is an AI summary of the original study and may miss details. Read our disclaimer.

Study facts

What this study's own registry entry says, in plain language.

Phase

Not a phased trial

Phase numbers describe drug development. The registry uses this when they do not apply, as it does for trials of devices, procedures or behaviour changes, and for observational studies.

Participants

About 20 people

The number the study aims to enrol. It can still change while the study runs.

Expected to start

Sep 2026

An estimate. Start dates often move.

Expected to finish

Dec 2026

An estimate. End dates often move.

Lead sponsor

Other sponsor

The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.

Who can take part

This study's own entry requirements. Only the study team can say for certain whether you qualify.

Ages

18 to 80 years

Sex

Anyone

Healthy volunteers

Not accepted

This study is not open to healthy volunteers. The entry requirements below say who it is open to.

Show the full entry requirements

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Adult patients aged 18-80 years and of all genders * Permanent residence \> 2600 m * Diagnosis of pulmonary arterial hypertension PAH (PAHHA-Group) according to guidelines * Patients are stable on therapy * NYHA (new york heart association) functional class I-III. * written informed consent to participate in the study. Exclusion Criteria: * Age \<18 years or \>80 years * unstable condition * Patients who cannot follow the study investigations * Patient permanently living \< 2600m. * Patients who traveled and stayed overnight at altitudes \<2000 m in the past 4 weeks. * Patients with moderate to severe concomitant lung disease (FEV1\<70% or forced vital capacity \<70%), severe parenchymal lung disease, severe smokers (\>20 cigarettes/day) * Severely hypoxemic patients at Quito permanently having persistent SpO2 (oxygen saturation by pulseoximetry) \<80% on ambient air. * Patient with a non-corrected ventricular septum defect * Relevant concomitant other disease of the heart, kidney, liver, blood (anemia hemoglobin\<11 g/dl)

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Conditions

The condition(s) this trial relates to.

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

How to take part

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  1. The places running it

    1 site. The list below names each one and where it is.

  2. The official record

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Contacts and locations

Locations

  • University Hospital of Zurich

    Zurich, 8091, Switzerland

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