Utility of Tissue Doppler Echocardiography for Selecting Patients for Cardiac Resynchronisation Therapy

Study Overview
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Brief Summary
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Currently the main selection tool for Cardiac Resynchronisation Therapy (CRT) is the QRS duration on the surface echocardiography (ECG) which has been shown to be a poor predictor of response. We sought to evaluate the use of tissue Doppler (TDI) assessment of dyssynchrony in prediction of response to CRT. The hypothesis is that the presence of mechanical dyssynchrony (measured using TDI echocardiography) successfully identifies heart failure patients who will respond to CRT. Conversely, the absence of mechanical dyssynchrony is associated with a low/no response to CRT. This is a three arm study. Group 1 comprises patients with dyssynchrony on TDI who are implanted with a biventricular ICD whereas Group 2 patients comprise patients who have no dyssynchrony. Group 2 patients are randomised 1:1 to either receive a biventricular ICD (2a) or an ICD (2b). All patients undergo a NYHA class assessment, a cardiopulmonary exercise test, and an echocardiogram at baseline and at 6 months follow up. Baseline and 6 months findings will be compared in all three groups.

Official Title
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Utility of Tissue Doppler Echocardiography for Selecting Patients for Cardiac Resynchronisation Therapy in Heart Failure

Conditions
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Heart Failure

Intervention / Treatment
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* Device: BiV ICD
* Device: ICD


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients must have an indication for ICD therapy Heart failure of any aetiology with evidence of left ventricular (LV) systolic dysfunction with LV ejection fraction < 35% and LV cavity dilatation (end diastolic dimension > 55 mm) NYHA Class III/IV symptoms of heart failure despite optimal medical therapy QRS duration ≥120ms Exclusion Criteria: Reversible cause of heart failure such as ongoing ischaemia amenable to revascularisation or treatable valvular disease Requirement for ventricular pacing due to atrioventricular block. Limited life expectancy (< 6 months)

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
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 1: Dyssynchrony positive<br> | Device: BiV ICD<br>* Biventricular ICD<br>|
| Active Comparator: 2a: Dyssynchrony negative<br> | Device: BiV ICD<br>* Biventricular ICD<br>|
| Active Comparator: 2b: Dyssynchrony negative<br> | Device: ICD<br>* Implantable Defibrillator<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiopulmonary Exercise Testing - changes in Peak VO2 from baseline to 6 months |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in New York Heart Association (NYHA) class from baseline to 6 months |  | 6 months | 
| Change in Quality-of-Life score from baseline to 6 months |  | 6 months | 
| Echocardiography - changes in left ventricular (LV) volume and dimensions, calculated ejection fractions and in severity of MR |  | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cardiac resynchronisation therapy, Tissue Doppler Imaging, Dyssynchrony