An interventional study of Descent from 2850m to sea level in Pulmonary Arterial Hypertension (PAH), Pulmonary Vascular Disease and High Altitude, sponsored by Silvia Ulrich Somaini. Not yet recruiting at 1 site in Switzerland. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-09-04.
Sponsored by Silvia Ulrich Somaini · Not applicable, Interventional, and Supportive care
To study the effect of relocation from high altitude (Quito Ecuador: 2850m) to sea level on pulmonary resistance (sPAP/CO) and other hemodynamic outcomes in patients with pulmonary arterial hypertension PAH, who live permanently >2600m.
The aim of this research is to investigate the pulmonary resistance (sPAP/CO) by echocardiography and other hemodynamic outcomes before and after relocation (high altitude near their living altitude vs. sea level) in patients with diagnosed pulmonary arterial hypertension according to guidelines, who permanently live at high altitude over 2600m.
699 studies on the registry are indexed under Pulmonary Arterial Hypertension; 140 are open to participants now.
This study's planned enrollment of 20 is below the median of 40 across 477 interventional studies indexed under Pulmonary Arterial Hypertension.
Browse Pulmonary Arterial Hypertension studies →Silvia Ulrich Somaini is the lead sponsor of 17 studies on the registry; 16 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
FEV1
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurement of pulmonary resistance (sPAP/CO) by echocardiography and other hemodynamic parameters near their resident altitude at 2850m followed by a descent from 2850m to sea level by bus with a stay for 7 days and again measurements by echocardiography
Behavioral: Descent from 2850m to sea level
Descent from 2850m to sea level with a stay for 7 days
Pulmonary resistance (sPAP/CO) after 7 days at sea level
Difference in sPAP/CO by echocardiography between 2850m and Day 5-7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to day 5-7 at sea level
Tricuspid regurgitation velocity TRV after 7 days at sea level
Difference in tricuspid regurgitation velocity TRV between 2850m and Day 5-7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to day 5-7 at sea level
Cardiac output CO after 7 days at sea level
Difference/change in cardiac output CO between 2850m and Day 5-7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850) to day 5-7 at sea level
Tricuspid annular plan systolic excursion TAPSE after 7 days at sea level
Difference/change in tricuspid annular plan systolic excursion TAPSE between 2850m and Day 5-7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to day 5-7 at sea level
Right ventricular strain after 7 days at sea level
Difference/change in right ventricular strain between 2850m and day 5-7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to Day 5-7 at sea level
Right atrial pressure RAP after 7 days at sea level
Difference/change in right atrial pressure RAP between 2850m and day 5-7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to Day 5-7 at sea level
Fractional area change FAC after 7 days at sea level
Difference/change in fractional area change FAC between 2850m and day 5-7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to Day 5-7 at sea level
PaO2 after 7 days at sea level
Difference/change in PaO2 (arterial blood gas analysis) between 2850m and sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850) to day 5-7 at sea level
PaCO2 after 7 days at sea level
Difference/change in PaCO2 (arterial blood gas analysis) between 2850m and sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850) to day 5-7 at sea level
Hemoglobin after 7 days at sea level
Difference/change in hemoglobin (arterial blood gas analysis) between 2850m and sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850) to day 5-7 at sea level
pH after 7 days at sea level
Difference/change in pH(arterial blood gas analysis) between 2850m and sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850) to day 5-7 at sea level
Acclimatization-Effect of pulmonary resistance (sPAP/CO) at sea level
Difference/change in pulmonary resistance (sPAP/CO) within a stay at sea level of 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 5-7 at sea level
Acclimatization-Effect of tricuspid regurgitation velocity TRV at sea level
Difference/change in tricuspid regurgitation velocity TRV within a stay at sea level of 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 5-7 at sea level
Acclimatization-Effect of cardiac output CO at sea level
Difference/change in cardiac output CO within a stay at sea level of 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 5-7 at sea level
Acclimatization-Effect of tricuspid annular plan systolic excursion TAPSE at sea level
Difference/change in tricuspid annular plan systolic excursion TAPSE within a stay at sea level for 7 days (after relocation from high altitude)
Time frame: From Day 2 to day 5-7 at sea level
Acclimatization-Effect of right ventricular strain at sea level
Difference/change in right ventricular strain within a stay at sea level for 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 5-7 at sea level
Acclimatization-Effect of right atrial pressure RAP at sea level
Difference/change in right atrial pressure RAP within a stay at sea level for 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 5-7 at sea level
Acclimatization-Effect of fractional area change FAC at sea level
Difference/change in fractional area change FAC within a stay at sea level for 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 5-7 at sea level
Acclimatization-Effect of PaO2 at sea level
Difference/change in PaO2 (arterial blood gas analysis) within a stay at sea level for 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 7 at sea level
Acclimatization-Effect of PaCO2 at sea level
Difference/change in PaCO2 (arterial blood gas analysis) within a stay at sea level for 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 7 at sea level
Acclimatization-Effect of hemoglobin at sea level
Difference/change in hemoglobin (arterial blood gas analysis) within a stay at sea level for 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 7 at sea level
Acclimatization-Effect of pH at sea level
Difference/change in pH (arterial blood gas analysis) within a stay at sea level for 7 days (after relocation from high altitude)
Time frame: From Day 2 to Day 7 at sea level
Plan to share: Yes — Data will be provided upon request and based on a clear intention reviewed by an ethical review board.
No publications or documents are linked to this record.
Start is estimated for Sep 2026; primary completion for Oct 2026, 0 months later.
Of 60 non-industry interventional studies with no phase under Pulmonary Arterial Hypertension, half reached primary completion within 44 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 63. This study's planned 0 months is below that.
Counting every sponsor, half of 65 studies reached it within 42 months; a quarter within 18 and three quarters within 71.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Pulmonary Arterial Hypertension →
Silvia Ulrich Somaini