Acute Excposure of High Altitude on ECG and Non-invasive Blood Pressure.

Study Purpose

Randomized crossover trial in patients with Pulmonary Hypertension (PAH, CTEPH) to assess the acute response of High Altitude (Säntis, 2500m above sea level) on ECG repolarizations and non-invasive blood pressure measurements by Finapres® NOVA Technology.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

Searching Both is inclusive of interventional and observational studies.

Eligible Ages 18 Years and Over
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - Informed consent - PH diagnosed according to internation Guidelines: mPAP ≥ 25 mmHg along with a PAWP ≤15 mmHg during right heart catheterization at the time of Initial diagnosis - PH class 1 (PAH) or 4 (CTEPH) - Stable condition, on the same medication for > 4 weeks - Patient live permanently at an altitude < 1000m asl.

Exclusion Criteria:

  • - Resting PaO2 ≤7.3 kPA corresponding to the requirement of long-term oxygen therapy > 16hour daily (nocturnal oxygen therapy alone is allowed) - Severe daytime hypercapnia (pCO2 > 6.5 kPa) - Susceptibility to high altitude related diseases (AMS, HAPE, etc.) based on previous experienced discomfort at altitudes.
- Exposure to an altitude >1500m for ≥3 nights during the last 4 weeks before the study participation - Residence > 1000m above sea level - Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, neurological or orthopedic problems with Walking disability - Women who are pregnant or breast feeding

Trial Details

Trial ID:

This trial id was obtained from, a service of the U.S. National Institutes of Health, providing information on publicly and privately supported clinical studies of human participants with locations in all 50 States and in 196 countries.


Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans.

Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use.

Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

University of Zurich
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

Silvia Ulrich, Prof.
Principal Investigator Affiliation University of Zurich
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Overall Status Enrolling by invitation
Countries Switzerland

The disease, disorder, syndrome, illness, or injury that is being studied.

Pulmonary Hypertension
Additional Details

Low altitude baseline measurements will be performed in Zurich (460m asl) including Echocardiography, Right heart catheterization, 6MWT, pulmonary function test, clinical assessment and blood gas Analysis. Randomly assigned to the order of testing, the participants will be tested in Low Altitude (Zurich, 470m) and at High Altitude (2500m). During the exposure High Alitude (2500m above sea level) and low alitude (Zurich) up to 5 hours, the participants' ECG and non-invasively assessed blood pressure by Finapres at rest and under exercise will be collected.

Arms & Interventions


Experimental: Order A

The participants will be tested in Zurich (Low altitude: 470m above sea level) and consecutively at High Altitude(Säntis; 2500m above sea Level)

Experimental: Order B

The participants will be tested at High Altitude (Säntis; 2500m above sea level) and consecutively in Zurich (Low altitude; 470m above sea level).


Other: - Low altitude: 470m above sea level

Assessment at Low Altitude (in Zurich; 470m above sea level) in order to compare this data with High altitude exposure

Other: - Säntis; 2500m above sea Level

Exposure to High Altitude (Säntis; 2500m above sea level) for approximately 5 hours

Contact a Trial Team

If you are interested in learning more about this trial, find the trial site nearest to your location and contact the site coordinator via email or phone. We also strongly recommend that you consult with your healthcare provider about the trials that may interest you and refer to our terms of service below.

International Sites

Zurich, Switzerland



Respiratory Clinic, University Hospital of Zurich

Zurich, , 8091

For more information, please contact PHA at and refer to the terms of service below.

Submit Feedback

The content provided on clinical trials is for informational purposes only and is not a substitute for medical consultation with your healthcare provider. We do not recommend or endorse any specific study and you are advised to discuss the information shown with your healthcare provider. While we believe the information presented on this website to be accurate at the time of writing, we do not guarantee that its contents are correct, complete, or applicable to any particular individual situation. We strongly encourage individuals to seek out appropriate medical advice and treatment from their physicians. We cannot guarantee the availability of any clinical trial listed and will not be responsible if you are considered ineligible to participate in a given clinical trial. We are also not liable for any injury arising as a result of participation in a clinical trial or study.