Risk Stratification and Benefits With Cardiac Resynchronization Therapy (CRT)

Study Overview
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Brief Summary
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This is an observational study to learn which patients benefit from CRT therapy and to track the clinical changes that help identify the risk-level of CRT patients.

Detailed Description
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The purpose of the study is two-fold. First, to determine if an algorithm can be developed based on pre-implant clinical variables to predict response to CRT-D therapy. Second, the study aims to determine in patients implanted with CRT-D if the combined use of cTnT and BNP can further predict and risk-stratify HF improvement and all-cause mortality. Additionally, novel biochemical markers defining cardiac mortality in high risk patients detected by plasma proteomic analysis in the CRT-D patients will be evaluated. This study represents a combination of previous CRT studies that evaluated these variables independently. Data from this study will be pooled with data from previous studies to build a more complete picture of CRT therapy.

Official Title
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Risk Stratification and Benefits With Cardiac Resynchronization Therapy

Conditions
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Heart Failure, Ventricular Arrhythmias

Intervention / Treatment
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* Device: CRT device implant


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Meets current clinical indications for CRT-D therapy Patient is 18 years old or older Ability to independently comprehend and complete all QOL questionnaires Patient has the ability to perform the 6-minute Hall Walk Test (6-MHW) with the only limiting factor being fatigue or shortness-of-breath Ability to provide informed consent for a study and be willing and able to comply with the prescribed follow-up Exclusion Criteria: Inability to successfully implant an intravascular lead and CRT-D device. (i.e. exclude epicardial leads) within 30 days of initial procedure. Myocardial infarction in the last 3 weeks Unstable angina in the last 3 weeks Status 1 classification for cardiac transplantation Currently participating in a clinical trial that includes an active treatment arm Life expectancy of less than 12 months. Recent (within 1 week) administration of Nesiritide™ or inotropes Patients in whom revascularization is expected Patient is pregnant

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| CRT device-recipients<br> | Device: CRT device implant<br>* CRT device-recipients<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in 6-minute hall walk distance between baseline and subsequent follow-up |  | 12 months | 
| Composite endpoint a. 6-minute hall walk distance b. NYHA Classification c. Quality of Life (Minnesota Living with Heart Failure, DASS, SF-36) |  | 12 months | 
| The occurrence of either death (all-cause) or first HF hospitalization. |  | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quality of Life |  | 12 months | 
| Change in echocardiographic variables including: a. Ejection Fraction b. Wall motion score c. Increase in TD velocity d. Yu index |  | 12 months | 
| Cause-specific mortality |  | 12 months |