HEXABM: Blood Markers Predict Effect of Normobaric Hypoxia at Rest and During Exercise in Patients With Pulmonary Hypertension

Sponsor

University of Zurich (Other)

Overall Status

Recruiting

CT.gov ID

NCT04715113

Collaborator

(none)

Enrollment

Location

Arms

46.9

Anticipated Duration (Months)

0.5

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

To study the effect of acute normobaric hypoxia during exercise in patients with pulmonary hypertension on blood markers (serum markers of iron and red blood cell homeostasis and micro-RNAs known to be associated with PH).

Condition or Disease	Intervention/Treatment	Phase
Hypertension, Pulmonary	Other: Normobaric hypoxia (FiO2 15%) Other: Placebo-ambient air (FiO2 21%) Other: Normobaric hypoxia (FiO2 15%) under Sildenafil Other: Placebo-ambient air (FiO2 21%) under Sildenafil	N/A

Study Design

Study Type:

Interventional

Anticipated Enrollment :

24 participants

Allocation:

Randomized

Intervention Model:

Crossover Assignment

Masking:

Single (Participant)

Primary Purpose:

Treatment

Official Title:

Hemodynamic Effects of Acute Normobaric Hypoxia During Exercise in Patients With Pulmonary Hypertension: Single-center Randomized Controlled Trial

Actual Study Start Date :

Feb 1, 2021

Anticipated Primary Completion Date :

Dec 31, 2023

Anticipated Study Completion Date :

Dec 31, 2024

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Normobaric hypoxia (FiO2 15%) Inhalation of deoxygenated air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.	Other: Normobaric hypoxia (FiO2 15%) Inhalation of deoxygenated air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.
Sham Comparator: Placebo-ambient air (FiO2 21%) Inhalation of room air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.	Other: Placebo-ambient air (FiO2 21%) Inhalation of room air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.
Experimental: Normobaric hypoxia (FiO2 15%) under Sildenafil Inhalation of deoxygenated air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.	Other: Normobaric hypoxia (FiO2 15%) under Sildenafil Inhalation of deoxygenated air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise under Sildenafil.
Active Comparator: Placebo-ambient air (FiO2 21%) under Sildenafil Inhalation of room air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.	Other: Placebo-ambient air (FiO2 21%) under Sildenafil Inhalation of room air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise under Sildenafil.

Outcome Measures

Primary Outcome Measures

Serum levels of ferritin [Baseline]
Analyis of serum levels of ferritin

Secondary Outcome Measures

Serum levels of transferrin [Baseline]
Analyis of serum levels of transferrin
Serum levels of total iron [Baseline]
Analysis of serum levels of total iron
Serum levels of erythropoietin [Baseline]
Analysis of serum levels of erythropoietin
Serum levels of Erythroferrone [Baseline]
Analysis of serum levels of erythroferrone
Serum levels of hepcidin [Baseline]
Analysis of serum levels of hepcidin
micro-RNA levels [Baseline]
Analysis of micro-RNA levels

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

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 Zürich altitude on ambient air
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
patients who take nitrates
other clinically significant concomitant end-stage disease (e.g., renal failure, hepatic dysfunction)