ECG Optimization of CRT: Evaluation of Mid-term Response

Study Overview
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Brief Summary
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New simpler methods to optimize cardiac resynchronization therapy (CRT) are being evaluated, such as the use of the electrocardiogram. In this prospective, double-blind, study, the investigators will evaluate: Primary endpoint: To compare the clinical response to CRT in patients with the programming optimized by QRS versus the nominal suggested by the device. Secondary endpoints: To compare cardiac remodeling in patients with the programming optimized by QRS versus the nominal suggested by the device. To evaluate the degree of asynchrony in both groups (nominal versus optimization by QRS) with respect to the intrinsic rhythm. To evaluate the echocardiographic improvement in left ventricular (LV) filling in both groups. To evaluate the differences in the optimal atrioventricular (AV) delay with atrial sensing or atrial pacing. For that, 180 patients with an indication for CRT will be randomized to nominal programming of the device or optimization by the electrocardiogram for a narrower QRS. A clinical and echocardiographic evaluation will be done at baseline, 6 and 12 months.

Official Title
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Optimization of Response to Cardiac Resynchronization Therapy by Electrocardiogram: an Assessment of Medium-term Response

Conditions
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Heart Failure

Intervention / Treatment
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* Other: Device programming: nominal
* Other: Programming optimization by QRS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with standard indication of cardiac resynchronization Ejection fraction ≤35%. QRS duration ≥120 ms. New York Heart Association Functional Class 2-4.. Left ventricular diameter ≥55 mm. Optimal medical treatment. Exclusion Criteria: Patient refusal. Cardiopathy with a reversible cause. Prevision of heart transplantation. Atrial fibrillation. Complete AV block. AV delay >250 ms. Right bundle branch block. Severe peripheral vascular disease. Other diseases with < 1 year life expectancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 99 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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Nominal<br>CRT device is programmed with the nominal values. | Other: Device programming: nominal<br>* CRT device is programmed to nominal values<br>|
| Experimental: Narrow QRS<br>CRT device is programmed by QRS optimization | Other: Programming optimization by QRS<br>* CRT device is programmed by QRS optimization<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical response | Clinical response: survival without heart transplantation or death and >10% increased distance in the 6MWT. | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Echocardiographic response | Echocardiographic response: >15% decrease in LV end-systolic volume and survival without heart transplantation or death. | 12 months | 
| Pacing/sensing AV delay difference |  | 12 months | 

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