The Effects of Anodal Stimulation on Echocardiographic Outcome in Patients With Cardiac Resynchronization Therapy

Study Overview
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Brief Summary
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To investigate the hemodynamic, inter and intraventricular desynchrony effects of anodal stimulation and triple site pacing compared with the usual dual site pacing by echocardiography and Tissue Doppler Imaging.

Detailed Description
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Thirty patients who underwent CRT and had evidence of anodal stimulation will be included in the study. All patients undergo a conventional echocardiography after 10 minutes of continuous triple site pacing and after 10 minutes of continuous dual site pacing (Customary biventricular pacing).Echocardiography studies will be performed to measure dP/dT using continuous flow Doppler velocity profiles of mitral regurgitation, LV volumes and Left ventricular ejection fraction. Left intraventricular desynchrony is assessed by using TDI.

Official Title
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The Effects of Anodal Stimulation on Left Ventricular Desynchrony and Hemodynamics in Patients With a Biventricular Pacemaker

Conditions
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Heart Failure

Intervention / Treatment
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* Device: Triple site pacing mode


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with biventricular pacemakers who met currently accepted indications for CRT, including dilated cardiomyopathy with LV ejection fraction < 35% (ischemic and nonischemic etiologies) with New York Heart Association class III to IV congestive heart failure and QRS duration > 120 ms. Exclusion Criteria: Patients with first generation CRT device Integrated bipolar defibrillator device Atrial fibrillation during the screening phase Patients who cannot tolerate triple site pacing for several minutes (i.e diaphragmatic pacing) Patients with epicardial LV leads Patients with LV leads located out of the lateral or posterolateral areas

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
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Dual site pacing (LV tip electrode and RV tip electrode) | |
| Experimental: Triple site pacing<br>Triple site pacing(LV tip electrode,RV tip electrode and RV ring electrode) | Device: Triple site pacing mode<br>* The experimental Triple site pacing mode includes pacing with Cardiac resynchronization therapy device using two leads; one in the right ventricle (RV) and one in the left ventricle (LV) but stimulates three sites: LV tip, RV tip and RV ring (instead of the usual two sites: LV tip and RV ring. Patients with evidence of improved LV dyssinchrony parameters during the triple pacing mode (anodal stimulation) will be programmed to anodal stimulation for 3 months.<br>* Other names: anodal stimulation, triple site pacing;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Myocardial Performance Index, dP/dT |  | After 10 minutes of triple site pacing and 10 minutes of dual sute pacing | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inter and intraventricular dyssynchrony parameters, LV volumes, LVEF |  | After 10 minutes of triple site pacing and 10 minutes of dual site pacing | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cardiac resynchronization therapy, Anodal stimulation