Effects of Normobaric Hypoxia During Exercise in Patients With Pulmonary Hypertension With/Without Sildenafil (HEXAS)

University of Zurich (UZH)

Status: Completed

Conditions: Hypertension, Pulmonary

Treatments: Other: Normobaric hypoxia (FiO2 15%); Other: Placebo-ambient air (FiO2 21%) under Sildenafil; Other: Normobaric hypoxia (FiO2 15%) under Sildenafil; Other: Placebo-ambient air (FiO2 21%)

Study type: Interventional

Funder types: Other

Identifiers

NCT04704440

2020-02163_A5

Details and patient eligibility

About

To study the effect of acute normobaric hypoxia during exercise in patients with pulmonary hypertension with/without Sildenafil

Enrollment: 24 patients

Sex: All

Ages: 18+ years old

Volunteers: No 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)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Single Blind

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24 participants in 4 patient groups

Normobaric hypoxia (FiO2 15%)

Experimental group

Description:

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.

Treatment:

Other: Normobaric hypoxia (FiO2 15%)

Placebo-ambient air (FiO2 21%)

Sham Comparator group

Description:

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.

Treatment:

Other: Placebo-ambient air (FiO2 21%)

Normobaric hypoxia (FiO2 15%) under Sildenafil

Experimental group

Description:

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.

Treatment:

Other: Normobaric hypoxia (FiO2 15%) under Sildenafil

Placebo-ambient air (FiO2 21%) under Sildenafil

Active Comparator group

Description:

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.

Treatment:

Other: Placebo-ambient air (FiO2 21%) under Sildenafil