Acute Exposure to High Altitude on Exercise Capacity

Acute Exposure to Hypoxia in Precapillary Pulmonary Hypertension: Physiological and Clinical Effects at Rest and During Exercise

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03637153

Enrollment

Registered

2018-08-17

Start date

2018-07-01

Completion date

2019-01-01

Last updated

2020-01-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pulmonary Hypertension

Keywords

exercise capacity, High Altitude, contant loaded exercise test

Brief summary

Randomized crossover Trial in patients with Pulmonary Hypertension (PAH, CTEPH) to assess the acute response to High Altitude (2500m above sea level) in constant loaded exercise capacity.

Detailed description

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). Towards the end of the exposure after approximately 4 hours, the participants will perform a constant loaded exercise test on an Ergometer with a calculated resistance of their 60% max Workload. The patients will be encouraged to perform these tests up to their physical exhaustion.

Interventions

OTHERAssessment at 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

OTHERExposure to High Altitude (2500m above sea level)

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

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

PREVENTION

Masking

NONE

Intervention model description

Including a baseline assessment and assessments at Low altitude and High altitude

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

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

Design outcomes

Primary

Measure	Time frame	Description
endurance time at High Altitude	1 day at altitude	The time of a constant loaded exercise test by an ergometer in sitting position at High Altitude will be compared with the same test at low altitude (370m above sea level)

Countries

Switzerland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 12, 2026