Maximal Exercise Capacity at 2500 m of High Altitude

The Impact of Hypoxia on Patients With Precapillary Pulmonary Hypertension and Treatment of Adverse Effects

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

Study Overview

• Status: Completed
• Conditions: High Altitude Pulmonary Hypertension; Maximal Exercise Capacity
• Intervention / Treatment: Procedure: Maximal Exercise Capacity

• Study Type: Interventional
• Enrollment (Actual): 28
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Zurich, Switzerland, 8091
    • Respiratory Clinic, University Hospital of Zurich

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: High altitude 2500 m above sea level (high altitude); Maximum Exercise Capacity in high altitude	Procedure: Maximal Exercise Capacity; Maximal Exercise Capacity in incremental ramp exercise tests.
Active Comparator: Low altitude 470 m above sea level (low altitude); Maximum Exercise Capacity in low altitude	Procedure: Maximal Exercise Capacity; Maximal Exercise Capacity in incremental ramp exercise tests.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maximal work rate	Change in maximal work rate in Watt at 2500 vs. 490 m	30 hours

Secondary Outcome Measures

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

Collaborators and Investigators

• Sponsor: University of Zurich

Study record dates

Study Major Dates

• Study Start (Actual): October 20, 2021
• Primary Completion (Actual): April 15, 2022
• Study Completion (Actual): April 15, 2022

Study Registration Dates

• First Submitted: October 14, 2021
• First Submitted That Met QC Criteria: February 21, 2022
• First Posted (Actual): March 3, 2022

Study Record Updates

• Last Update Posted (Actual): May 11, 2022
• Last Update Submitted That Met QC Criteria: May 10, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Respiratory Tract Diseases; Lung Diseases; Hypertension; Hypertension, Pulmonary
• Other Study ID Numbers: OVERALP II D

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No