Maximal Exercise Capacity at 2500 m of High Altitude

Not Applicable

Completed

• Conditions: High Altitude Pulmonary Hypertension; Maximal Exercise Capacity
• Interventions: Procedure: Maximal Exercise Capacity

• Registration Number: NCT05264324
• Lead Sponsor: University of Zurich

Brief Summary

The impact of hypoxia on maximal work rate during incremental ramp exercise within 3-6 hours after arriving at 2500m of high altitude in patients with precapillary pulmonary hypertension

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-10-14
• Study Start: 2021-10-20
• Study First Submitted QC: 2022-02-21
• Study First Posted: 2022-03-03
• Primary Completion: 2022-04-15
• Study Completion: 2022-04-15
• Status Verified: 2022-05
• Last Update Submitted: 2022-05-10
• Last Update Posted: 2022-05-11

Recruitment & Eligibility

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

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 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)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
High altitude 2500 m above sea level (high altitude)	Maximal Exercise Capacity	Maximum Exercise Capacity in high altitude
Low altitude 470 m above sea level (low altitude)	Maximal Exercise Capacity	Maximum Exercise Capacity in low altitude

Primary Outcome Measures

Name	Time	Method
Maximal work rate	30 hours	Change in maximal work rate in Watt at 2500 vs. 490 m

Secondary Outcome Measures

Name	Time	Method
Rate pressure product	30 hours	Change of corrected Rate pressure product, during cycle exercise tests at high vs. low altitude
Electro cardiography: Clinically relevant ischemia	30 hour	Incidence of clinically relevant ischemia (\>1mm ST-segment depression) during cycle exercise tests at high altitude vs. low altitude
Electro cardiography: QT-Interval	30 hours	Change of corrected QRS duration, during cycle exercise tests at high vs. low altitude
Electro cardiography: PQ-Interval	30 hours	Change of corrected PQ-Interval, during cycle exercise tests at high vs. low altitude
Electro cardiography: ST-segment changes under oxygen	30 hours	7Difference in ST-segment changes during cycle exercise tests without and with oxygen at high altitude
Heart rate	30 hours	Change in cardiorespiratory measurements: heart rate during a cycle incremental ramp exercise test at high altitude vs. low altitude
Ventilation	30 hours	Change in cardiorespiratory measurements: ventilation during a cycle incremental ramp exercise test at high altitude vs. low altitude
Electro cardiography	30 hours	Prevalence of abnormal resting electro cardiography (ECG) at high altitude vs. low altitude
Oxygen uptake	30 hours	Change in cardiorespiratory measurements: Oxygen uptake, SpO2, blood gases during a cycle incremental ramp exercise test at high altitude vs. low altitude
Arterial blood oxygenation saturation	30 hours	Change in cardiorespiratory measurements: Oxygenation (SpO2) during a cycle incremental ramp exercise test at high altitude vs. low altitude
Blood gases	30 hours	Change in blood gases during a cycle incremental ramp exercise test at high altitude vs. low altitude
Borg dyspnoea and leg fatigue scale	30 hours	Change in post-exercise Borg dyspnoea and leg fatigue scale during a cycle incremental ramp exercise test at high altitude vs. low altitude
Electro cardiography :ST-segment changes	30 hours	Difference in ST-segment changes during cycle incremental ramp and constant work-rate exercise tests at high altitude vs. low altitude
Hemodynamics	30 hours	Change in hemodynamics assessed by echocardiography
Visual Analogue Scale for dyspnea	30 hours	Change Visual Analogue Scale at high altitude vs. low altitude according to a 10cm scale from left to right, where the subject has to mark dyspnea with higher values in cm meaning worse dyspnea
Electro cardiography: Cardiac arrhythmia	30 hours	Incidence of cardiac arrhythmia during cycle exercise tests at high altitude vs. low altitude

Trial Locations

Locations (1)

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