An interventional study of Re-Ascent from sea level to 2850m 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 a re-ascent after a one-week stay at sea level (after prior descent from 2850m) to high altitude (Quito Ecuador: 2850m) 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 re-ascent (sea level for 7 days vs. re-ascent to 2850m) 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.
Assessment of pulmonary resistance (sPAP/CO) and other hemodynamic parameters after 7 days at sea level with re-ascent from sea level back to 2850m by bus (in one day) and assessment of the same outcomes
Behavioral: Re-Ascent from sea level to 2850m
After 7 days at sea level return/re-ascent to their usual living altitude at 2850m
Pulmonary resistance (sPAP/CO) after re-ascent to 2850m
Difference in sPAP/CO by echocardiography between sea level (after one-week stay) and day after re-ascent at 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 5-7 at sea level to day after re-ascent
Tricuspid regurgitation velocity TRV after re-ascent to 2850m
Difference/change in tricuspid regurgitation velocity TRV between sea level (after one-week stay) and day after re-ascent at 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 5-7 at sea level to day after re-ascent
Cardiac output CO after re-ascent to 2850m
Difference/change in cardiac output CO between sea level (after one-week stay) and Day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 5-7 at sea level to the day after re-ascent
Tricuspid annular plan systolic excursion TAPSE after re-ascent to 2850m
Difference/change in tricuspid annular plan systolic excursion TAPSE between sea level (after one-week stay) and Day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 5-7 at sea level to day after re-ascent
Right ventricular strain after re-ascent to 2850m
Difference/change in right ventricular strain between sea level (after one-week stay) and Day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 5-7 at sea level to day after re-ascent
Right atrial pressure RAP after re-ascent to 2850m
Difference/change in right atrial pressure RAP between sea level (after one-week stay) and Day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 5-7 at sea level to day after re-ascent
Fractional area change FAC after re-ascent to 2850m
Difference/change in fractional area change FAC between sea level (after one-week stay) and Day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 5-7 at sea level to day after re-ascent
PaO2 after re-ascent to 2850m
Difference/change in PaO2 (arterial blood gas analysis) between sea level (after one-week stay) and day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 7 at sea level to day after re-ascent (time frame of 3 days)
PaCO2 after re-ascent to 2850m
Difference/change in PaCO2 (arterial blood gas analysis) between sea level (after one-week stay) and day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 7 at sea level to day after re-ascent (time frame of 3 days)
Hemoglobin after re-ascent to 2850m
Difference/change in hemoglobin (arterial blood gas analysis) between sea level (after one-week stay) and day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 7 at sea level to day after re-ascent (time frame of 3 days)
pH after re-ascent to 2850m
Difference/change in pH (arterial blood gas analysis) between sea level (after one-week stay) and day after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Day 7 at sea level to day after re-ascent (time frame of 3 days)
Pulmonary resistance (sPAP/CO) pre-descent to after re-ascent
Difference/change in pulmonary resistance (sPAP/CO) at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Tricuspid regurgitation velocity TRV pre-descent to after re-ascent
Difference/change in tricuspid regurgitation velocity TRV at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Cardiac output CO pre-descent to after re-ascent
Difference/change in cardiac output CO at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Tricuspid annular plan systolic excursion TAPSE pre-descent to after re-ascent
Difference/change in tricuspid annular plan systolic excursion TAPSE at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Right ventricular strain pre-descent to after re-ascent
Difference/change in right ventricular strain at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Right atrial pressure RAP pre-descent to after re-ascent
Difference/change in right atrial pressure RAP at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Fractional area change FAC pre-descent to after re-ascent
Difference/change in fractional area change FAC at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
PaO2 pre-descent to after re-ascent
Difference/change in PaO2 (arterial blood gas analysis) at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
PaCO2 pre-descent to after re-ascent
Difference/change in PaCO2 (arterial blood gas analysis) at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Hemoglobin pre-descent to after re-ascent
Difference/change in hemoglobin (arterial blood gas analysis) at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
pH pre-descent to after re-ascent
Difference/change in pH (arterial blood gas analysis) at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in patients with pulmonary arterial hypertension
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
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.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Pulmonary Arterial Hypertension →
Silvia Ulrich Somaini