A Study to Evaluate the Effect of Vagus Nerve Stimulation in Patients Undergoing VT Ablation

Study Overview
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Brief Summary
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Vagus nerve stimulation (VNS) has been shown to be beneficial in multiple studies including heart failure. The goal of this clinical investigation is to gain additional information about how vagus nerve stimulation relates to abnormal heart rhythms. The outcomes of this study will help researchers design new therapies for patients that have complex and life-threatening ventricular arrhythmias.

Detailed Description
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This study is a non-randomized, prospective study in 6 patients with scar mediated ventricular arrhythmias who are scheduled to undergo a catheter ablation procedure. The study will last up to 30 minutes in the cardiac electrophysiology lab. Cervical VNS is performed percutaneously through the internal jugular vein during the patient's routine ventricular tachycardia (VT) ablation procedure.

Official Title
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A Study to Evaluate the Effect of Vagus Nerve Stimulation in Patients Undergoing Ventricular Tachycardia (VT) Ablation

Conditions
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Arrhythmia, Ventricular Tachycardia (VT)

Intervention / Treatment
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* Other: Vagus Nerve Stimulation (VNS)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Presence of structural heart disease as defined as EF ≤ 50% or presence of ventricular scar as detected by imaging modalities or electroanatomic mapping, hypertrophic cardiomyopathy, cardiac sarcoidosis, or arrhythmogenic right ventricular cardiomyopathy. Age > 18 years old Underlying sinus rhythm with heart rate > 50 bpm. Provision of signed/dated informed consent and stated willingness to comply with all study procedures Exclusion Criteria: Active ongoing cardiac ischemia as assessed by: ECG, cardiac enzymes, symptoms, coronary angiography with evidence of significant epicardial coronary stenosis (>70%), or stress testing. (Note: positive troponin assay due to Internal Cardiac Defibrillator (ICD) shocks is not an exclusion criterion). Status post orthotopic heart transplantation Women who are pregnant (as evidenced by pregnancy test if pre-menopausal). Unable or unwilling to comply with protocol requirements. Known channelopathy such as long QT syndrome, Brugada syndrome, and catecholaminergic polymorphic VT. Known peripheral neuropathy or history of autonomic dysfunction due to non-cardiac causes. New York Heart Association Class IV heart failure or use of current vasopressor medications Incessant VT Persistent atrial fibrillation Frequent premature atrial or ventricular contractions Inability to give informed consent.

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: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Vagus Nerve Stimulation (VNS)|Vagus Nerve Stimulation (VNS) will be performed percutaneously through the internal jugular vein during the patient's routine VT ablation procedure. The nerve will be stimulated using standard pacing systems used for clinical purposes. A series of stimulation frequencies and pulse widths will be used to define optimal effects and 'dosing'. Activation recovery interval (ARI) will be measured from the unipolar electrograms. In addition, heart rate and blood pressure responses will be continuously recorded.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The change in ventricular action potential duration during stimulation compared to baseline in msec |  | Up to 30 minutes or completion of the vagus nerve stimulation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The change in blood pressure during stimulation compared to baseline in mmHg. |  | Up to 30 minutes or completion of the vagus nerve stimulation | 
| The change in heart rate during stimulation compared to baseline in beats per minute |  | Up to 30 minutes or completion of the vagus nerve stimulation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Arrhythmia, Vagus Nerve Stimulation (VNS), Activation Recovery Interval (ARI)