Assessment of Heart Rate Variability HRV During Descent DE From 2850m to Sea Level and During Re-ascent A From Sea Level to 2850m in Patients With Pulmonary Arterial Hypertension PAH

Effect of a One-week Descent From 2850m to Sea Level and Re-ascent in Patients With Pulmonary Arterial Hypertension and Healthy Controls Permanently Living > 2600m on Pulmonary Hemodynamics, Exercise Capacity, Blood Oxygenation, Sleep Disordered Breathing and Further Outcomes

To study the effect of relocation from high altitude (Quito Ecuador: 2850m) to sea level and re-ascent from sea level to 2850m on heart rate variability and other hemodynamic parameters in patients with pulmonary arterial hypertension PAH, who live permanently >2600m.

Study Overview

• Status: Not yet recruiting
• Conditions: High Altitude; Pulmonary Arterial Hypertension (PAH); High Altitude Effects; Pulmonary Vascular Disease; ECG Abnormalities; Heart Rate Variability (HRV)
• Intervention / Treatment: Behavioral: Descent and re-ascent (2850m, sea level)

Detailed Description

The aim of this research is to investigate the heart rate variability and other hemodynamic outcomes during the descent from 2850m to sea level and during re-ascent from sea level to 2850m in patients with diagnosed pulmonary arterial hypertension according to guidelines, who permanently live at high altitude over 2600m

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Silvia Ulrich, Prof. Dr. med.; Phone Number: +41442552220; Email: silvia.ulrich@usz.ch
• Study Contact Backup: Name: Michael Furian, Prof. Dr. sc. ETH; Phone Number: +41442552220

Study Locations

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

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients aged 18-80 years and of all genders
• Permanent residence > 2600 m
• Diagnosis of pulmonary arterial hypertension PAH (PAHHA-Group) according to guidelines
• Patients are stable on therapy
• NYHA (new york heart association) functional class I-III.
• 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 < 2600m.
• Patients who traveled and stayed overnight at altitudes <2000 m in the past 4 weeks.
• 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 having persistent SpO2 (oxygen saturation by pulseoximetry) <80% on ambient air.
• Patient with a non-corrected ventricular septum defect
• Relevant concomitant other disease of the heart, kidney, liver, blood (anemia hemoglobin<11 g/dl)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Heart rate variability HRV during descent and re-ascent; Assessment of heart rate variability and other hemodynamic outcomes in patients with pulmonary arterial disease during descent from 2850m to sea level and during re-ascent from sea level (after one week stay) back near their living altitude at 2850m	Behavioral: Descent and re-ascent (2850m, sea level); Descent from 2850m to sea level (in one day by bus) and re-ascent after 7 days from sea level to 2850m (in one day by bus)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart rate variability HRV during descent and re-ascent	Difference/change in heart rate variability at different altitudes during descent (2850m to sea level) and during re-ascent after 7 days (sea level to 2850m) in patients with pulmonary arterial hypertension	From day of descent (day 1) and day of re-ascent (day 8)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
SpO2 during descent and re-ascent	Difference/change in SpO2 at different altitudes during descent (2850m to sea level) and during re-ascent after 7 days (sea level to 2850m) in patients with pulmonary arterial hypertension	From day of descent (day 1) and day of re-ascent (day 8)
ECG-Repolarization during descent and re-ascent	Difference/change in ECG-repolarization at different altitudes during descent (2850m to sea level) and during re-ascent after 7 days (sea level to 2850m) in patients with pulmonary arterial hypertension	From day of descent (day 1) and day of re-ascent (day 8)
Cardial arrhythmias during descent and re-ascent	Occurrence/changes in cardial arrhythmias at different altitudes during descent (2850m to sea level) and during re-ascent after 7 days (sea level to 2850m) in patients with pulmonary arterial hypertension	From day of descent (day 1) and day of re-ascent (day 8)
Pulse transit time during descent and re-ascent	Occurrence and difference/change in pulse transit time (drops) at different altitudes during descent (2850m to sea level) and during re-ascent after 7 days (sea level to 2850m) in patients with pulmonary arterial hypertension	From day of descent (day 1) and day of re-ascent (day 8)

Collaborators and Investigators

• Sponsor: Silvia Ulrich Somaini
• Investigators: Principal Investigator: Silvia Ulrich, University Hospital Zurich, Departement of Pulmonology; Principal Investigator: Rodrigo Hoyos, Hospital Carlos Andrade Marin of Quito, Ecuador

Study record dates

Study Major Dates

• Study Start (Estimated): September 25, 2026
• Primary Completion (Estimated): October 4, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: August 17, 2026
• First Submitted That Met QC Criteria: August 31, 2026
• First Posted (Actual): September 3, 2026

Study Record Updates

• Last Update Posted (Actual): September 3, 2026
• Last Update Submitted That Met QC Criteria: August 31, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: Pulmonary hypertension; Heart rate variability; ECG; High altitude; Arrythmias; Pulse transit time; Pulmonary vascular disease; Pulmonary arterial hypertension PAH
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Respiratory Tract Diseases; Lung Diseases; Respiration Disorders; Hypertension; Pulmonary Arterial Hypertension; Hypertension, Pulmonary; Altitude Sickness
• Other Study ID Numbers: Ec_DEvsA_HRV_PAH

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data will be provided upon request and based on a clear intention reviewed by an ethical review board.

Drug and device information, study documents

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