Cardiac Strains for Optimization of CRT in Non-Responders

Study Overview
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Brief Summary
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The aim of this study is to investigate the possibility of optimizing the performance of CRT-D in non-responding patients through utilization of cardiac strain speckle tracking

Detailed Description
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In approximately 30% of patients, cardiac resynchronization therapy (CRT) fails to lead to any improvement of the patients' status. In this study, an investigation of a possible method of optimization through speckle tracking of cardiac strains is attempted. Patients not responding to Cardiac Resynchronization Therapy-Defibrillators (CRT-D) after 3 months are randomly divided into control and intervention groups. Atrioventricular interval is adjusted so that E and A waves do not overlap and the interventricular interval subsequently optimized to yield maximum improvement of the sum of longitudinal+radial+circumferential strains. The left ventricular ejection fraction (LVEF) and NYHA (New York Heart Association Classification improvement 3 months after optimization are evaluated and use of other strain combinations assessed.

Official Title
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Use of Cardiac Strains for Optimization of Cardiac Resynchronization Therapy in Non-Responders

Conditions
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Chronic Heart Failure

Intervention / Treatment
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* Device: CRT-D re-programming
* Diagnostic Test: Trans-Thoracic Echocardiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with symptomatic heart failure with NYHA III/IV, pharmacological treatment options exhausted, LVEF below 30%, and QRS duration over 130ms who did not respond to the implantation of CRT-D Exclusion Criteria: Age below 18 response to the original CRT implantation

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
Interventional Model Description: Patients not responding to Cardiac Resynchronization Therapy-Defibrillators (CRT-D) after 3 months from implementation are randomly divided into control and intervention groups. Atrioventricular interval is adjusted so that E and A waves do not overlap, the interventricular interval iss subsequently optimized to yield maximum improvement of the sum of longitudinal+radial+circumferential strains. The left ventricular ejection fraction (LVEF) and NYHA (New York Heart Association Classification improvement 3 months after optimization are evaluated and the use of other strain combinations assessed.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CRT-D re-programming<br>The ineffective previously implanted CRT-D is reprogrammed under supervision of transthoracic echocardiography to: adjust the atrioventricular interval so that E and A waves do not overlap the interventricular interval is subsequently optimized to yield maximum improvement of the sum of longitudinal+radial+circumferential strains. Transthoracic echocardiography is performed prior to optimization and 3 months after optimization (i.e., 3 and 6 months after the CRT implantation) and and New York Heart Association Classification (NYHA Classification; total score range 1-4) is being determined in accordance with the standard NYHA methods re-programming of the interventricular interval | Device: CRT-D re-programming<br>* The previously implanted, ineffective CRT-D is reprogrammed under supervision of Trans-Thoracic Echocardiography (TTE) to: adjust the atrioventricular interval so that E and A waves do not overlap the interventricular interval is subsequently optimized to yield maximum improvement of the sum of longitudinal+radial+circumferential strains.<br>Diagnostic Test: Trans-Thoracic Echocardiography<br>* This intervention relates to the determination of strains and atrioventricular interval and supplies data for reprogramming the ineffective CRT-D Transthoracic echocardiography performed to determine the left ventricular ejection fraction as an outcome measure is not considered intervention here (as it is also performed in the control group and that would cause an error cross-referencing.<br>|
| No Intervention: Control Group<br>Only trans-thoracic echocardiography is performed during follow-ups at 3 and 6 months from CRT implantations performed and New York Heart Association Classification (NYHA Classification; total score range 1-4) is being determined in accordance with the standard NYHA methods | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the left ventricular ejection fraction | Left ventricular ejection fraction measured by transthoracic echocardiography prior to optimizing and during a follow-up examination three month after optimizing | 6 months from CRT-D implantation, 3 months from optimization | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in NYHA Classification | NYHA (New York Heart Association Classification measured using the standard NYHA range I to IV - I being the best result, IV the worst) was evaluated using a standard NYHA questionnaire before optimization and 3 months after optimization during a follow-up examination | 6 months from CRT-D implantation, 3 months from optimization | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cardiac resynchronization therapy, non-responders