High Altitude Pulmonary Hypertension
Conditions
Brief summary
The impact of a sojourn at 2500 m of high altitude for 26-30 h on constant work-rate exercise test time in patients with precapillary pulmonary hypertension
Detailed description
Patients with pulmonary hypertension will perform a constant work-rate exercise test at low altitude (450m) and at high altitude 2500m in a randomized-cross-over sequence protocol. The constant work-rate exercise test time and other measures will be assessed
Interventions
PROCEDUREHigh altitude exposure
Exposure to 2500m of altitude
PROCEDURELow altitude exposure
Exposure to 490 m
Sponsors
University of Zurich
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
SCREENING
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Informed consent as documented by signature * 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 Zurich at 490 m low altitude * 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 * other clinically significant concomitant end-stage disease (e.g., renal failure, hepatic dysfunction)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| cycle constant work-rate exercise test | 30 hours | Difference in cycle constant work-rate exercise test (CWRET) time at 2500 vs. 490 m (Time Frame 24 to 30 hours) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Ventilation in liters per minute | 30 hours | Difference in cardiorespiratory measurements: Ventilation assessed in liters per minute, during a cycle constant work-rate exercise test (CWRET) time at high altitude vs. low altitude |
| Visual analogue scale | 30 hours | Difference in baseline in symptoms assessed by the Visual Analogue Scale at high altitude vs. low altitude |
| Oxygen uptake | 30 hours | Difference in cardiorespiratory measurements: oxygen uptake, during a cycle constant work-rate exercise test (CWRET) time at high altitude vs. low altitude |
| Oxygen saturation | 30 hours | Difference in cardiorespiratory measurements: Oxygen saturation, during a cycle constant work-rate exercise test (CWRET) time at high altitude vs. low altitude |
| Heart rate | 30 hours | Difference in cardiorespiratory measurements: Heart rate, during a cycle constant work-rate exercise test (CWRET) time at high altitude vs. low altitude |
| Tricuspid pressure gradient | 30 hours | Trans-tricuspid pressure gradient by echocardiography |
| Borg dyspnoea scale | 30 hours | Difference in post-exercise Borg dyspnoea and leg fatigue scale during a cycle constant work-rate exercise test (CWRET) time at high altitude vs. low altitude |
| sit-to-stand test frequency | 30 hours | Difference in baseline in sit-to-stand test frequency of standing up from a chair in a minute at high altitude vs. low altitude |
| 6 minute walk test | 30 hours | Difference in baseline in 6 minute walk test distance at high altitude vs. low altitude |
| Partial pressure or oxygen | 30 hours | Difference in partial pressure of oxygen at the beginning and end of a cycle constant work-rate exercise test (CWRET) time at high altitude vs. low altitude |
Countries
Switzerland
Outcome results
None listed