High Altitude Pulmonary HypertensionNCT06489756
Highlanders With High Altitude Pulmonary Hypertension (HAPH), Pulmonary Arterial Pressure (PAP) Assessed at 3200m With and Without Supplemental Oxygen Therapy (SOT)
A study testing Echocardiography in people with High Altitude Pulmonary Hypertension, run by University of Zurich at 1 site in Kyrgyzstan.
Trial summary
The investigators aim to study the effect of SOT in highlanders with high altitude pulmonary hypertension (HAPH) who permanently live >2500m on pulmonary arterial pressure (PAP) assessed at 3200 m. Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- High Altitude Pulmonary Hypertension
- What is being tested?
- Echocardiography
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 48 participants
- Where
- 1 siteKyrgyzstan
- Study dates
- 1 Jul 2024to 31 Dec 2024
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Permanently living >2500 m
- HAPH diagnosed with a minimum RV/RA of 30 mmHg assessed by echocardiography at an altitude of 3200 m
- Written informed consent
Who cannot join
- Highlanders who cannot follow the study investigations,
- Patients with moderate to severe concomitant lung disease (FEV1<70% or forced vital capacity <70%), severe parenchymal lung disease, heavy smoking >20 cigarettes/day or >20 pack-years.
- Coexistent unstable systemic hypertension or coronary artery disease that required adjustment of medication within the last 2 months
- Regular use of medication that affects control of breathing (benzodiazepines, opioids, acetazolamide)
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Effect of Supplemental Oxygen Therapy (SOT) on Pulmonary Arterial Pressure in Highlanders With High Altitude Pulmonary Hypertension Permanently Living at >2500m
The investigators aim to study the effect of SOT in highlanders with high altitude pulmonary hypertension (HAPH) who permanently live >2500m on pulmonary arterial pressure (PAP) assessed at 3200 m.
Read the detailed description
Highlanders with HAPH diagnosed by echocardiography and defined by a RV/RA (Tricuspid Regurgitation Pressure Gradient) >30 mmHg will be recruited for this project. Highlanders permanently living at HA >2500 m will have echocardiografy to assess PAP near their living altitude in Aksay at 3200 m with and without 10L/min supplemental oxygen therapy (SOT) via face mask.
- Conditions
- High Altitude Pulmonary Hypertension
- Being tested
- Echocardiography
- Keywords
- Pulmonary Hypertension, Hypoxia, High Altitude, Supplemental Oxygen Therapy, Pulmonal Arterial Pressure
- Medical subject headings
- Pulmonary edema of mountaineers, Hypertension, Pulmonary, Hypoxia, Altitude Sickness
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
EchocardiographyOther
Echocardiography will be performed according to clinical standards
| Study group | Role | What they receive |
|---|---|---|
| Ambient air | Active comparator | Highlanders with HAPH will perform the echocardiography on ambient air at 3200m Receives: Other: Echocardiography |
| 10 L/min SOT through face mask | Experimental | Supplemental oxygen therapy (SOT) at 10 L/min will be provided via face mask from oxygen concentrators Receives: Other: Echocardiography |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Pulmonary Artery Pressure with SOT vs.ambient air at 3200m
Change in RV/RA in mmHg assessed by echocardiography with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Secondary outcomes (8)
Change in Cardiac Output with SOT vs. ambient air at 3200m
Change in cardiac output (l/min) assessed by echocardiography with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Change in right to left heart diameter ratio with SOT vs.ambient air at 3200m
Change in right to left heart diameter ratio assessed by echocardiography with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Change in tricuspid annular plane systolic excursion (TAPSE) with SOT vs.ambient air at 3200m
Change in tricuspid annular plane systolic excursion (TAPSE) with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Change in right atrial area with SOT vs. ambient air at 3200m
Change in right atrial area by echocardiography with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Change in right heart strain with SOT vs. ambient air at 3200m
Change in right heart strain by echocardiography with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Change in pH by arterial blood gases with SOT vs. ambient air at 3200m
Changes in pH by arterial blood gases with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Change in PaO2 by arterial blood gases with SOT vs. ambient air at 3200m
Changes in PaO2 by arterial blood gases with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Change in PaCO2 by arterial blood gases with SOT vs. ambient air at 3200m
Changes in PaCO2 by arterial blood gases with SOT compared to ambient air at 3200m
Measured: at 15 min of breathing ambient air or supplemental oxygen
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Jul 2024
- Study start1 Jul 2024
- Primary completion31 Dec 2024
- Study completion31 Dec 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for High Altitude Pulmonary HypertensionStudies of the same condition, open and under way.
- More trials run by University of ZurichThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Crossover
- Model description
- Each highlander with HAPH will perform a echocardiography with and without SOT according to a cross-over design
- Masking
- None (open label)
- Enrolment
- 48 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Zurich
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Talant MA Sooronbaev, Prof. Dr., Principal investigator, National Center of Cardiology and Internal Medicine named after academician M.MirrakhimovSilvia Ulrich, Prof. Dr., Principal investigator, University Hospital Zurich, Department of Pulmonology
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06489756
- Sponsor's protocol ID
- HAPH_SOT_PAP
- Status last verified
- Nov 2025
- First submitted
- 28 Jun 2024
- Last updated
- 4 Dec 2025
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Vella A, Muller J, Omuralieva A, Titz A, Mayer L, Mademilov M, Lichtblau M, Furian M, Sooronbaev T, Ulrich S. Effects of high-dose supplemental oxygen therapy on pulmonary haemodynamics at 3250 m in high-altitude residents at risk for pulmonary hypertension. BMJ Open Respir Res. 2026 Oct 1;13(1):e004376. doi: 10.1136/bmjresp-2026-004376.
PubMed 42823120
Study at a glance
From the registry record, last updated by the sponsor on 4 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of Supplemental Oxygen Therapy (SOT) on Pulmonary Arterial Pressure in Highlanders With High Altitude Pulmonary Hypertension Permanently Living at >2500m
- ClinicalTrials.gov ID
- NCT06489756
- Acronym / sponsor ID
- HAPH_SOT_PAP
- Conditions
- High Altitude Pulmonary Hypertension
- Keywords
- Pulmonary Hypertension, Hypoxia, High Altitude, Supplemental Oxygen Therapy, Pulmonal Arterial Pressure
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 48 participants (actual)
- Lead sponsor
- University of ZurichUniversity, hospital or other
- Study start
- 1 Jul 2024 (actual)
- Primary completion
- 31 Dec 2024 (actual)
- Study completion
- 31 Dec 2024 (actual)
- First posted
- 8 Jul 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The investigators aim to study the effect of SOT in highlanders with high altitude pulmonary hypertension (HAPH) who permanently live >2500m on pulmonary arterial pressure (PAP) assessed at 3200 m.
Detailed description
Highlanders with HAPH diagnosed by echocardiography and defined by a RV/RA (Tricuspid Regurgitation Pressure Gradient) >30 mmHg will be recruited for this project. Highlanders permanently living at HA >2500 m will have echocardiografy to assess PAP near their living altitude in Aksay at 3200 m with and without 10L/min supplemental oxygen therapy (SOT) via face mask.
Study design
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Each highlander with HAPH will perform a echocardiography with and without SOT according to a cross-over design
| Arm | Type | Receives |
|---|---|---|
| Ambient air | Active comparator | Other: EchocardiographyHighlanders with HAPH will perform the echocardiography on ambient air at 3200m |
| 10 L/min SOT through face mask | Experimental | Other: EchocardiographySupplemental oxygen therapy (SOT) at 10 L/min will be provided via face mask from oxygen concentrators |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Permanently living >2500 m
- HAPH diagnosed with a minimum RV/RA of 30 mmHg assessed by echocardiography at an altitude of 3200 m
- Written informed consent
Key exclusion criteria (4 listed)
- Highlanders who cannot follow the study investigations,
- Patients with moderate to severe concomitant lung disease (FEV1<70% or forced vital capacity <70%), severe parenchymal lung disease, heavy smoking >20 cigarettes/day or >20 pack-years.
- Coexistent unstable systemic hypertension or coronary artery disease that required adjustment of medication within the last 2 months
- Regular use of medication that affects control of breathing (benzodiazepines, opioids, acetazolamide)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| EchocardiographyEchocardiography will be performed according to clinical standards | Other | 10 L/min SOT through face mask, Ambient air |
Primary outcome
Change in Pulmonary Artery Pressure with SOT vs.ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Change in RV/RA in mmHg assessed by echocardiography with SOT compared to ambient air at 3200m
8 secondary outcomes
Change in Cardiac Output with SOT vs. ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Change in right to left heart diameter ratio with SOT vs.ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Change in tricuspid annular plane systolic excursion (TAPSE) with SOT vs.ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Change in right atrial area with SOT vs. ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Change in right heart strain with SOT vs. ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Change in pH by arterial blood gases with SOT vs. ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Change in PaO2 by arterial blood gases with SOT vs. ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Change in PaCO2 by arterial blood gases with SOT vs. ambient air at 3200m
Time frame: at 15 min of breathing ambient air or supplemental oxygen
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Dec 2025.
- Derived from this study: PubMed 42823120Vella A, Muller J, Omuralieva A, Titz A, Mayer L, Mademilov M, Lichtblau M, Furian M, Sooronbaev T, Ulrich S. Effects of high-dose supplemental oxygen therapy on pulmonary haemodynamics at 3250 m in high-altitude residents at risk for pulmonary hypertension. BMJ Open Respir Res. 2026 Oct 1;13(1):e004376. doi: 10.1136/bmjresp-2026-004376.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Talant MA Sooronbaev, Prof. Dr. principal investigator
National Center of Cardiology and Internal Medicine named after academician M.Mirrakhimov
Silvia Ulrich, Prof. Dr. principal investigator
University Hospital Zurich, Department of Pulmonology
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Echocardiography in people with High Altitude Pulmonary Hypertension, run by University of Zurich at 1 site in Kyrgyzstan.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 4 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Kyrgyzstan. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Pulmonary Artery Pressure with SOT vs.ambient air at 3200m (time frame: at 15 min of breathing ambient air or supplemental oxygen). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06489756, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Dec 2025.