Effect of Acute Hypoxia on RIght VEntRicular Function in Asthma.
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18-80
SponsorMona Lichtblau
About this trial
More and more people are engaging in sports in the mountains, including individuals with heart or lung diseases. At the same time, such diseases are becoming more common in Switzerland. At high altitude, less oxygen is available, which places stress on the body-particularly on the heart, which has to pump blood through the lungs. How the heart, especially the right ventricle, in people with asthma responds to this stress is still not well understood.
Therefore, this study investigates how the heart responds to simulated altitudes of 2,500 m and 4,000 m, both at rest and during light physical activity in patients with asthma. The primary objective is to assess how right ventricular function changes under conditions of reduced oxygen availability.
In addition, vital signs, changes in blood gases, oxygen levels in blood and tissue and shortness of breath are assessed. The "altitude" is simulated using a special gas mixture that participants inhale. Participants undergo three altitude conditions (490, 2,500, and 4,000 m above sea level). The order of the altitude conditions is assigned at random.
The aim is to better understand how the right ventricle and other parameters respond to low-oxygen conditions and how affected patients can be better supported in the future.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
Signed informed consent
Diagnosed and well controlled asthma bronchiale
18-80 years (age group young: 18-39.99 years / age group older: 40-80 years)
All sex and genders
Disqualifiers
<18, >80 years old
Any other diagnosed cardiopulmonary condition including past HAPE
Other clinically significant severe concomitant disease states (e.g. renal, hepatic dysfunction, etc.)
Inability to follow the procedures of the study due to language problems, psychological neurological disorders or orthopaedic disorders
Trial design
Design model
Crossover
Treatments tested in this trial
Normobaric Hypoxia
Other interventionNormobaric hypoxia according to 408m (control/normobaric normoxia), 2500 m and 4000 m above sea-level at rest for 1 hour and at low intensity cycling for 10 minutes (5 min 30 W, 5 min 60 W).
Treatment groups
18 Participants
are divided into 6 treatment groups6
Treatment groupsSee each treatment group below.
Group A: Arm ABC (normobaric normoxia - normobaric hypoxia 2500m - normobaric hypoxia 4000m)Other 1 intervention
Group B: Arm ACB (normobaric normoxia - normobaric hypoxia 4000m - normobaric hypoxia 2500m)Other 1 intervention
Group C: Arm BAC (normobaric hypoxia 2500m - normobaric normoxia - normobaric hypoxia 4000m)Other 1 intervention
Group D: Arm BCA (normobaric hypoxia 2500m - normobaric hypoxia 4000m - normobaric normoxia)Other 1 intervention
Group E: Arm CAB (normobaric hypoxia 4000m - normobaric normoxia - normobaric hypoxia 2500m)Other 1 intervention
Group F: Arm CBA (normobaric hypoxia 4000m - normobaric hypoxia 2500m - normobaric normoxia)Other 1 intervention
Trial outcomes
Primary outcomes
1
Right ventricular free wall strain
The primary endpoint is defined as the right ventricular free wall strain (RVFWS) from condition normobaric normoxia to condition 4000m for group 1 and from normobaric normoxia to condition 2500m for group 2 at rest. RVFWS will be measured by speckle tracking strain analysis according to the guidelines of the European Association of Cardiology. Speckle tracking echocardiography allows to assess the right ventricular volume and true global RV function without relying on geometric assumption and is a valuable clinical bedside tool for assessing myocardial strain. Tomtec software (Philipps) will be used.
Time frame
It will be assessed once at baseline in rest and during each condition three times: Once after 1 hour in the specific condition at rest, then during the 5 min of 30 Watt cycling and during the 5 min of 60 Watt cycling.Secondary outcomes
1
Tricuspid annular plane systolic excursion (TAPSE)
Differences in tricuspid annular plane systolic excursion (TAPSE) \[cm\] between the conditions at rest and during exercise, measured according to the guidelines of the European Association of cardiology.
Time frame
It will be assessed once at baseline in rest and during each condition three times: Once after 1 hour in the specific condition at rest, then during the 5 min of 30 Watt cycling and during the 5 min of 60 Watt cycling.2
Right ventricular-arterial coupling
Differences in TAPSE/sPAP and RVFWS/sPAP between the conditions at rest and during exercise, measured by echocardiography, as a validated, noninvasive measure of right ventricular-arterial coupling.
Time frame
It will be assessed once at baseline in rest and during each condition three times: Once after 1 hour in the specific condition at rest, then during the 5 min of 30 Watt cycling and during the 5 min of 60 Watt cycling.3
RV/PA
Differences in RV/PA ratio between the conditions at rest and during exercise, measured by echocardiography according to the guidelines of the European Association of cardiology.
Time frame
It will be assessed once at baseline in rest and during each condition three times: Once after 1 hour in the specific condition at rest, then during the 5 min of 30 Watt cycling and during the 5 min of 60 Watt cycling.4
Stroke volume
Differences in stroke volume based on the left ventricular outflow tract diameter and the velocity time integral over the aortic valve in the apical 5-chamber view or the apical long axis view \[ml\] between the conditions at rest and during exercise, measured by speckle tracking strain analysis according to the guidelines of the European Association of Cardiology.
Time frame
It will be assessed once at baseline in rest and during each condition three times: Once after 1 hour in the specific condition at rest, then during the 5 min of 30 Watt cycling and during the 5 min of 60 Watt cycling.Sponsors and contacts
Click on the lead sponsor to view all of their trials.
Mona Lichtblau
Lead sponsor
University of Zurich
Sponsor institution
Source ClinicalTrials.gov