Acute Exposure to High Altitude on Exercise Capacity

Not Applicable

Completed

• Conditions: Pulmonary Hypertension
• Interventions: Other: Assessment at Low Altitude (470m above sea level); Other: Exposure to High Altitude (2500m above sea level)

• Registration Number: NCT03637153
• Lead Sponsor: University of Zurich

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.

Study Timeline

• Study Start: 2018-07-01
• Study First Submitted: 2018-07-09
• Study First Submitted QC: 2018-08-16
• Study First Posted: 2018-08-17
• Primary Completion: 2019-01-01
• Study Completion: 2019-01-01
• Status Verified: 2020-01
• Last Update Submitted: 2020-01-06
• Last Update Posted: 2020-01-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 28

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Order A	Assessment at Low Altitude (470m above sea level)	Firstly, the participants will have their assessments at low altitude (Low altitude: 470m above sea level) in Zurich and consecutively the exposure to High Altitude (Säntis; 2500m above sea Level).
Order B	Assessment at Low Altitude (470m above sea level)	Firstly, the participants will exposed to High Altitude (Säntis; 2500m above sea level) and consecutively will they have assessement in Zurich (Low altitude; 470m above sea level).
Order A	Exposure to High Altitude (2500m above sea level)	Firstly, the participants will have their assessments at low altitude (Low altitude: 470m above sea level) in Zurich and consecutively the exposure to High Altitude (Säntis; 2500m above sea Level).
Order B	Exposure to High Altitude (2500m above sea level)	Firstly, the participants will exposed to High Altitude (Säntis; 2500m above sea level) and consecutively will they have assessement in Zurich (Low altitude; 470m above sea level).

Primary Outcome Measures

Name	Time	Method
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)

Trial Locations

Locations (1)

Respiratory Clinic, University Hospital of Zurich; 🇨🇭 Zurich, Switzerland