Is Mitral Velocity Time-integral a Marker of Preload-responsiveness in Patients With Acute Circulatory Failure?

Study Overview
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Brief Summary
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The aim of this is to assess the reliability of the variability of the mitral velocity time-integral with passive leg raising to predict the fluid responsiveness in patients with acute circulatory failure in intensive care.

Detailed Description
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Adult patients with acute circulatory failure will be included in the study. An initial echocardiography is performed in patients placed in a semi-recumbent position. On the apical views (4 and 5-chamber views), the left ventricular outflow tract velocity time integral (LVOT-VTI) and mitral valve (MV-VTI) velocity time integral are measured (baseline values). Then a passive leg raise test is performed and the parameters (LVOT-VTI and MV-VTI) are measured again. Preload-responsiveness is defined by an increase in LVOT-VTI of at least 10%. In preload-responsive patients, a fluid loading with 500 ml of 0.9% saline administered over 15 minutes is performed. Immediately after fluid therapy, the same parameters are recorded during a third echocardiography. An increase of 10% or more of LVOT-VTI , compared with baseline, defines fluid responsiveness. Patients are monitored using the standard of care practices. Hemodynamic assessment includes repetitive echocardiographic examinations if needed. In patients with shock, invasive blood pressure is monitored with an arterial catheter.

Official Title
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Reliability and Accuracy of Mitral Velocity Time-integral Variability With Passive Leg Raising as a Marker of Preload-responsiveness in Patients With Acute Circulatory Failure in the ICU.

Conditions
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Preload-responsiveness

Intervention / Treatment
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* Diagnostic Test: Echocardiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Acute circulatory failure. Exclusion Criteria: Recent surgery (<5 days) Suspected or confirmed intra-abdominal hypertension. Intracranial hypertension. Severe mitral valve disease: Severe mitral insufficiency or severe mitral stenosis Acute cor pulmonale Atrial fibrillation Low echogenicity

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

| Intervention/Treatment |
| --- |
|Diagnostic Test: Echocardiography|Mitral velocity time-integral variability measurement before and after passive leg raising. Mitral velocity time-integral variability measurement after fluid loading in preload-responsiveness patients.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reliability and accuracy of the change in mitral valve velocity time-integral (cm) to discriminate preload-responsiveness | Reliability and accuracy of the change in mitral valve velocity time-integral (cm) measured by echocardiography (before and after passive leg raising) to discriminate preload-responsive patients. | through study completion, an average of 6 months | 
| Reliability and accuracy of the change in mitral valve velocity time-integral (cm) to discriminate fluid-responsiveness | Reliability and accuracy of the change in mitral valve velocity time-integral (cm) measured by echocardiography (before and after fluid loading with 500 ml of saline) to discriminate fluid-responsive patients. | through study completion, an average of 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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preload-responsiveness, acute circulatory failure, left ventricular outflow tract velocity time integral, mitral valve velocity time integral, echocardiography