Predicting Response to CRT Using Body Surface ECG Mapping

Study Overview
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Brief Summary
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Cardiac resynchronization therapy (CRT) involves pacing the left and right side of the heart in order to improve the coordination of the contraction in patients with heart failure. Current selection criteria incorporate the severity of the symptoms, the mechanical function of the heart and the time it takes the electrical stimulation to spread over the left ventricle (as assessed on the standard 12 lead electrocardiogram-ECG). Unfortunately these criteria only seem to select approximately 70% of the patients who might respond to this invasive therapy. Body surface ECG mapping is a new technique that assesses the electrical activation of the heart in more detail than the standard ECG. This study aims to determine whether this new technology may aid current selection criteria in predicting response to CRT.

Official Title
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Evaluation of a Novel Method of Non-surface Electrocardiographic Mapping in Predicting Clinical, Structural and Neurohormonal Responses in Patients Undergoing Cardiac Resynchronization Therapy.

Conditions
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Heart Failure

Intervention / Treatment
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* Device: CRT Implant
* Device: Body Surface ECG Mapping


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age >18 years old Fulfils established clinical criteria for CRT implantation (with or without a defibrillator) NYHA Class III-IV Heart Failure (or NYHA II with NYHA III/IV symptoms in the preceding 12 months) LVEF <35% (Calculated using echocardiography or Cardiac MR) at the time of implantation QRS duration > 130ms Optimal Tolerated Medical Therapy for Heart Failure Exclusion Criteria: Severe, life threatening non cardiac disease Active malignant disease and recent (<5 years) malignant disease Prior Heart Transplant Recent history of unstable angina, acute coronary syndrome or myocardial infarction within three months of enrolment into the study Pregnancy Failure to participate in consent process Atrial Fibrillation Conventional pacemaker in situ Heart Failure requiring constant intravenous therapy including diuretics and/or inotropes Recent revascularisation procedure i.e. coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) within the last three 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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CRT Eligible<br>ACC/AHA/HRS/ESC guidelines for device-based therapy | Device: CRT Implant<br> <br> * Other names: Biventricular Pacemaker;Device: Body Surface ECG Mapping<br> <br> * Other names: ECG Imaging;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in distance travelled during six-minute walk test (6MWT) |  | Baseline and 6 months | 
| Echocardiographic: signs of LV reverse remodelling | Increase by >5% in left ventricular ejection fraction with an associated decrease in LV end-diastolic (LVEDV) and end-systolic (LVESV) volumes | Baseline and 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Symptoms | Change in symptoms severity assessed by Minnesota Living With Heart Failure Questionnaire (MLHFQ) | Baseline and 6 months | 
| Neurohormonal status | Change in neurohormonal activation assessed by brain-natriuretic peptide (BNP) | Baseline and 6 Months | 
| Pacing | Atrial and ventricular arrhythmic burden, percentage of bi-ventricular pacing | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Heart Failure, Cardiac Resynchronization Therapy, ECG Imaging, Body Surface Mapping