Genetic Substudy of the Alternans Before Cardioverter Defibrillator (ABCD) Trial

Study Overview
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Brief Summary
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The ABCD clinical study (ClinicalTrials.gov Identifier NCT00187291) was designed to determine if a T-Wave Alternans (TWA) test is equivalent to an Electrophysiology Study (EPS) in predicting life-threatening heart rhythms in patients with ischemic heart disease, left ventricular dysfunction, and non-sustained tachycardia. The purpose of the ABCD Genetic sub-study is to identify genetic markers that predict TWA status and arrhythmia risk in this same population.

Detailed Description
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The primary objective of this study is to test the hypothesis that therapy directed primarily by a T wave alternans (TWA) test, measured non-invasively during exercise, is equivalent to therapy directed by an electrophysiological study (EPS) in predicting spontaneous ventricular tachyarrhythmic events (VTEs) in patients with ischemic heart disease, left ventricular dysfunction, and asymptomatic non-sustained ventricular tachycardia (NSVT). In the absence of any previous life-threatening ventricular arrhythmia (i.e., for primary prevention), ICD implantation is currently indicated in patients with ischemic heart disease, left ventricular dysfunction, asymptomatic non-sustained ventricular tachycardia, and a positive EPS. The objective of this study is to demonstrate that a TWA test directed therapy is equivalent to EPS directed therapy in guiding ICD implantation for the purpose of primary prevention of sudden cardiac death (SCD) in patients with ischemic heart disease, left ventricular dysfunction, and asymptomatic non-sustained ventricular tachycardia.

Official Title
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Identifying Genetic Markers That Predict Microvolt T-wave Alternans Status and Arrhythmia Risk in Patients With Ischemic Heart Disease

Conditions
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Ventricular Tachycardia, Cardiovascular Diseases, Arrythmia, CVD

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects previously enrolled in the ABCD trial sponsored by St. Jude Medical (ClinicalTrials.gov Identifier NCT00187291) patients with ischemic heart disease left ventricular ejection fraction (LVEF) < 40% non-sustained ventricular tachycardia Exclusion Criteria: Individuals who were not previously enrolled in the ABCD trial are not eligible for this genetic sub-study.

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 |
| --- | --- |
| ABCD Subjects<br>The cohort will consist of original subjects of the ABCD trial who consent to participate in the genetic sub-study | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Genotype and Pre-implant T-wave alternans status. | Genotype and Pre-implant T-wave alternans status. | two years as per original ABCD trial | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Genotype and occurrence of appropriate cardioversion | Genotype and occurrence of appropriate cardioversion for ventricular tachycardia or ventricular fibrillation | two years per original ABCD trial | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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GES, Arrhythmia, Heart Failure, T-wave Alternans, Implanted Cardioverter Defibrillator, Biological Markers, Molecular Genetics, Corus CAD, ASGES, Age/Sex/Gene Expression Score, Gene Expression, CVD, Precision Medicine, Sudden Cardiac Death, Electrophysiology Study, Cardiovascular Disease, ICD, EPS, SCD, TWA