High Altitude (HA) Residents With Pulmonary Vascular Diseases (PVD), 6 Minute Walk Distance (6MWD) Assessed at 2840m (HA) With and Without Supplemental Oxygen Therapy (SOT)

University of Zurich (UZH)

Status: Active, not recruiting

Conditions: Pulmonary Artery Hypertension; Chronic Thromboembolic Pulmonary Hypertension; Pulmonary Vascular Disease

Treatments: Other: 6-minute walk distance (6MWD) test; Other: 6-minute walk distance (6MWD) test with supplemental oxygen (3 l/min, nasal)

Study type: Interventional

Funder types: Other

Identifiers

NCT06003244

PVD_HA_SOT_6MWD

Details and patient eligibility

About

The investigators aim to study the effect of SOT in participants with pulmonary vascular diseases (PVD) defined as pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension (PH) who permanently live >2500m on 6-minute walk distance (6MWD) assessed at 2840m.

Full description

Participants with PVD diagnosed with precapillary PH with right heart catheterization and classified to groups 1 and 4 (PAH or CTEPH) who permanently live at HA >2500 (PVDHA) will have 6-minute walk distance near their living altitude in Quito at 2840m with and without SOT at 3l/min via nasal cannula according to a randomized cross-over design.

Enrollment: 24 estimated patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

IInclusion Criteria:

• Adult patients 18-80 years old of both genders,
• Residence > 2500m of altitude
• diagnosed with precapillary PH (mean pulmonary artery pressure (mPAP) >20 mmHg, pulmonary artery wedge pressure (PAWP) ≤15 mmHg and pulmonary vascular resistance (PVR) ≥2 wood units (WU) by right heart catheterization) with PH being classified as PAH or CTEPH according to guidelines
• Patients stable on therapy
• New York Heart Association (NYHA) functional class I-III
• Provided written informed consent to participate in the study.

Exclusion Criteria:

• Age <18 years or >80 years
• unstable condition
• Patients who cannot follow the study investigations, patient permanently living < 2500m.
• Patients with moderate to severe concomitant lung disease (FEV1<70% or forced vital capacity <70%), severe parenchymal lung disease, severe smokers (>20 cigarettes/day)
• Severely hypoxemic patients at Quito permanently have persistent oxygen saturation by pulseoximetry (SpO2) <80% on ambient air.
• Patients with chronic mountain sickness (Hemoglobin > 19 g/dl in women, >21 g/dl in men)
• Patient with a non-corrected ventricular septum defect
• Relevant concomitant other disease of the heart, kidney, liver, blood (anemia hemoglobin<11 g/dl)

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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24 participants in 2 patient groups

Ambient air

Active Comparator group

Description:

Patient will perform tests on ambient air at 2840 m

Treatment:

Other: 6-minute walk distance (6MWD) test

SOT via nasal canula

Experimental group

Description:

Supplemental oxygen therapy (SOT) at 3l/min will be provided via a nasal cannula from a small oxygen bottle carried on the back according to standard care

Treatment:

Other: 6-minute walk distance (6MWD) test with supplemental oxygen (3 l/min, nasal)