Echocardiography in Cardiac Resynchronization Therapy (Echo-CRT)

Study Overview
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Brief Summary
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The present observational prospective study aims at identifying echocardiographic parameters (based on the Left Bundle Branch Block (LBBB)-like contraction of the left ventricle (LV) ascertained using new methods of echocardiography including speckle tracking strain) that are linked to Cardiac Resynchronization Therapy (CRT) response and a better outcome following CRT

Detailed Description
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The Cardiac Resynchronization Therapy (CRT) reduces mortality of patients with heart failure and reduced LV ejection fraction. The clinical benefit of CRT is mediated by LV reverse remodelling (decrease in LV end-systolic volume over time). However, 30 to 50 % of these patients will not experience LV reverse remodelling following CRT. Classical parameters of dyssynchrony obtained by conventional methods of echocardiography (including doppler tissue imaging) have a limited value in predicting CRT response. Meanwhile, patients with a Left Bundle Branch Block (LBBB) on the electrocardiogram experience more frequently LV reverse remodelling than those without a LBBB. LBBB is responsible for specific LV contractile abnormalities that can be identified by speckle tracking strain echocardiography (early septal contraction, stretching of late contraction of the postero-lateral wall). The predictive value of these abnormalities remains to be studied. Thus, it has been hypothesised that these LBBB-related contractile abnormalities may be independent predictors of LV reverse remodelling and outcome following CRT. The present observational prospective study aims at identifying echocardiographic parameters (based on the LBBB-like contraction of the LV ascertained using new methods of echocardiography including speckle tracking strain) that are linked to CRT response and a better outcome following CRT.

Official Title
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Prediction of Response to Cardiac Resynchronization Therapy by New Echocardiographic Methods

Conditions
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Heart Failure, Cardiac Resynchronization Therapy

Intervention / Treatment
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* Other: Echocardiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Heart failure with left ventricular ejection fraction less than 35 % QRS duration over than 120 ms Clinical indication for CRT Exclusion Criteria: Rythmologic indication of CRT for atrial fibrillation control Rythmologic indication of CRT for left ventricular ejection fraction between 35% and 45%

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 |
| --- | --- |
| Patients with heart failure and CRT<br>Heart failure with left ventricular ejection fraction less than 35 % treated with CRT | Other: Echocardiography<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in left ventricular end-systolic volume measured by echocardiography |  | 9 months after implantation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Death rate |  | 2, 4, 6, 8 and 10 years after implantation | 
| re-hospitalisation rate |  | 2, 4, 6, 8 and 10 years after implantation | 
| Changes in left ventricular ejection fraction measured by echocardiography |  | 9 months after implantation | 
| Changes in left ventricular end-diastolic volume measured by echocardiography |  | 9 months after implantation | 
| Changes in left ventricular longitudinal strain measured by echocardiography |  | 9 months after implantation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cardiac Resynchronization Therapy, Echocardiography, Biventricular Pacing