Hypertension, Pulmonary
Conditions
Keywords
hypoxia, exercise, hemodynamics
Brief summary
To study hemodynamic effects of acute normobaric hypoxia during exercise in patients with pulmonary hypertension in a single-center randomized controlled trial.
Interventions
Inhalation of deoxygenated air through an altitude simulator (Altitrainer), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.
Inhalation of room air through an altitude simulator (Altitrainer), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.
Sponsors
University of Zurich
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Informed consent as documented by signature (Appendix Informed Consent Form) * PH class I (PAH) or IV (CTEPH) diagnosed according to guidelines: mean pulmonary artery pressure \>20 mmHg, pulmonary vascular resistance ≥3 wood units, pulmonary arterial wedge pressure ≤15 mmHg during baseline measures at the diagnostic right-heart catheterization
Exclusion criteria
* resting partial pressure of oxygen \<8 kilopascal at Zürich altitude on ambient air * exposure to an altitude \>1000 m for ≥3 nights during the last 2 weeks before the study * inability to follow the procedures of the study * patients who take nitrates * other clinically significant concomitant end-stage disease (e.g., renal failure, hepatic dysfunction)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| mean pulmonary artery pressure (mPAP) / cardiac output (CO) | 2 hours | Difference in mPAP/CO during exercise between tests under hypoxia vs. normoxia |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Differences in pulmonary arterial pressure | 2 hours | Differences in pulmonary arterial pressure at rest and during exercise, with normoxia/hypoxia |
| Differences in cardiac output | 2 hours | Differences in cardiac output at rest and during exercise, with normoxia/hypoxia |
| Pulmonary vascular resistance | 2 hours | Differences in pulmonary vascular resistance at rest and during exercise, with normoxia/hypoxia |
| Differences in pulmonary artery wedge pressure | 2 hours | Differences in pulmonary artery wedge pressure at rest and during exercise, with normoxia/hypoxia |
| Differences in right atrial pressure | 2 hours | Differences in right atrial pressure at rest and during exercise, with normoxia/hypoxia |
| Differences in mixed venous oxygen saturation | 2 hours | Differences in mixed venous oxygen saturation at rest and during exercise, with normoxia/hypoxia |
| Differences in blood pressure | 2 hours | Differences in blood pressure at rest and during exercise, with normoxia/hypoxia |
| Differences in heart rate | 2 hours | Differences in heart rate at rest and during exercise, with normoxia/hypoxia |
| Differences in arterial blood gases | 2 hours | Differences in arterial blood gases at rest and during exercise, with normoxia/hypoxia |
| Differences in mixed venous blood gases | 2 hours | Differences in mixed venous blood gases at rest and during exercise, with normoxia/hypoxia |
| Differences in cerebral tissue oxygenation | 2 hours | Differences in cerebral tissue oxygenation at rest and during exercise, with normoxia/hypoxia |
| Differences in muscle tissue oxygenation | 2 hours | Differences in muscle tissue oxygenation at rest and during exercise, with normoxia/hypoxia |
| Differences in symptoms (Borg dyspnoea) | 2 hours | Differences in symptoms (Borg dyspnoea) at rest and during exercise, with normoxia/hypoxia |
| Differences in symptoms (Borg leg effort) | 2 hours | Differences in symptoms (Borg leg effort) at rest and during exercise, with normoxia/hypoxia |
| Differences in oxygen saturation | 2 hours | Differences in oxygen saturation at rest and during exercise, with normoxia/hypoxia |
Countries
Switzerland
Outcome results
None listed