Effects of Endoscopic Lung Volume Reduction on Diaphragm Function and Conformation

Study Overview
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Brief Summary
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Chronic obstructive lung disease (COPD) is a common disease that is frequently complicated by hyperinflation. The resulting increase in lung volume impairs the diaphragmatic function because of a shortening of the diaphragmatic fibers and an increase in the radius of curvature of the diaphragmatic domes. Lung volume reduction surgery (LVRS) has already shown an improvement in diaphragmatic function that could be explained by a change of the diaphragm conformation. More recently, endoscopic lung volume reduction (ELVR) has shown benefits in terms of respiratory function, exercise capacity and quality of life, but the mechanisms of these improvements are poorly understood. Therefore, we aim to evaluate the evolution of the diaphragmatic function and the changes in diaphragmatic conformation after unilateral ELVR.

Official Title
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Effects of Endoscopic Lung Volume Reduction on Diaphragm Function and Conformation

Conditions
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COPD

Intervention / Treatment
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* Device: Endoscopic lung volume reduction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: valves insertion Exclusion Criteria: TLVR < 50 %

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Interventional Model Description: Before and after study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Endoscopic lung volume reduction<br>All the patients will have endobronchial valves insertion. We will evaluate before and 3 months after the evolution of the diaphragmatic strength and conformation. | Device: Endoscopic lung volume reduction<br>* a prospective monocentric study on hyperinflated COPD patients without collateral ventilation. Patients were evaluated before and 3 months after unilateral ELVR by transdiaphragmatic pressure (Pdi) measured at the functional residual capacity (FRC) after magnetic phrenic stimulation and by high-resolution computed tomography at the FRC allowing 3D modelling of the diaphragm for measurements of fibers length, length of the zone of apposition and radius of curvature of the diaphragmatic domes.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Transdiaphragmatic pressure | evaluate the difference in diaphragmatic function, assessed by the transdiaphragmatic pressure, before and 3 months after unilateral valves setting | before until 3 months after the valves insertion | 
| Diaphragmatic conformation | evaluate the change of the diaphragm conformation, by measuring diaphragmatic fibers length in several planes, diaphragmatic area and radius of curvature, before and 3 months after unilateral ELVR. | before until 3 months after the valves insertion |