Detection of Right Ventricular Dysfunction by 2D Strain During Acute Respiratory Distress Syndrom (ARDS)

Study Overview
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Brief Summary
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Acute respiratory distress syndrome (ARDS) and mechanical ventilation can lead to right ventricular dysfunction and ultimately right ventricular failure by increasing pulmonary vascular resistances and pressure load. This can be prevented by modifying ventilator settings, using vasopressors or inotropes or even by prone positionning.But to do so, right ventricular dysfonction has to be detected. Echocardiography has emerged as a first line tool to diagnose right heart failure. Recently, strain analysis showed promising results to detect early right ventricle abnormalities in other settings such as pulmonary hypertension or scleroderma. We therefore decided to determine whether 2D strain could help detect early right ventricular dysfunction in ARDS.

Official Title
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Detection of Right Ventricular Dysfunction by 2D Strain During Acute Respiratory Distress Syndrom (ARDS)

Conditions
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Acute Respiratory Distress Syndrome, Right Ventricular Dysfunction, Right Heart Failure, Acute Cor Pulmonale

Participation Criteria
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Eligibility Criteria
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ARDS group Inclusion Criteria: Need for mechanical ventilation ARDS criteria met: Respiratory failure not fully explained by cardiac failure, Pao2/FiO2<200, bilateral opacities on Chest imaging, all symptoms appeared within 1 week Exclusion Criteria: Predictable duration of mechanical ventilation shorter than 48 hours Contraindication to transesophageal echocardiography ALI group: Inclusion Criteria: Need for mechanical ventilation ALI criteria met: Respiratory failure not fully explained by cardiac failure, Pao2/FiO2<300, bilateral opacities on Chest imaging, all symptoms appeared within 1 week Exclusion Criteria: Predictable duration of mechanical ventilation shorter than 48 hours Control Group: Inclusion Criteria: Need for mechanical ventilation for a non-respiratory cause Exclusion Criteria: Need for FiO2>30% Known cardiac abnormalities Cardiac drugs intake during last 24 hours

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| ARDS group<br>Patients under mechanical ventilation since less than 24 hours at inclusion and presenting acute respiratory distress syndrome criteria. | |
| ALI group<br>Patients under mechanical ventilation and presenting acute lung injury criteria. | |
| Control Group<br>Patients under mechanical ventilation for a non-respiratory cause | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Right ventricle 2D strain | We will assess whether 2D strain can detect a right ventricular dysfunction as compared to standard echocardiographic parameters | Duration of mechanical ventilation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean right ventricle strain under ventilated patients | We measure right ventricle strain (RV strain) in patients under mechanical ventilation for a non-respiratory cause. This allows us to determine the mean value of RV strain under ventilation when there is no respiratory failure. | at inclusion | 
| Reproducibility between transthoracic and transesophageal strain measures | In ARDS patients, we record a transthoracic and transesophageal echocardiography. We compare RV strain values obtained from transthoracic and transesophageal echocardiography. | Time of mechanical ventilation | 
| NT pro BNP and pre pro endothelin plasma level | These assays are made based on the hypothesis they could help discriminate between patients who will develop a right ventricular dysfunction from those who will not. A blood sample is withdrawn at the same time as echocardiography only in the ARDS group. | At inclusion in ARDS patients |