Optimization of VNS in Epileptic Patients to Induce Cardioprotection

Study Overview
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Brief Summary
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This study is a non-randomized, prospective study in patients with a diagnosis of epilepsy and previously implanted FDA approved Vagus Nerve Stimulation (VNS) devices. The goal of this clinical investigation is to evaluate the effects of adjusting vagus nerve stimulation parameters to engage cardioprotective effects.

Detailed Description
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Epilepsy patients are at increased risk for sudden cardiac death. Mechanisms behind this predisposition is poorly understood but parasympathetic dysfunction is heavily implicated. Vagus Nerve Stimulation (VNS) protocols currently set for seizure management are poorly optimized for cardioprotection, therefore this patient population presents a unique opportunity to assess VNS control of cardiac function, when VNS is appropriately titrated for cardiac and seizure benefit. This study will enroll 12 patients with a diagnosis of epilepsy and previously implanted FDA approved VNS devices. The study will last up to 9 weeks and the patient will undergo changes to their VNS settings during autonomic testing and cardiopulmonary testing.

Official Title
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A Feasibility Study to Evaluate the Safety and Effect of the Optimization of Vagus Nerve Stimulation in Epileptic Patients to Induce Cardioprotection

Conditions
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Epilepsy, Sudden Cardiac Death

Intervention / Treatment
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* Other: A change or titration in the current or frequency settings of the VNS therapy system.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical diagnosis of refractory epilepsy and implanted with a VNS device or are scheduled to be implanted with a VNS device. 18 years of age or older Subjects must demonstrate willingness and ability to comply with study requirements Exclusion Criteria: Other implantable neuromodulatory device (e.g., brain stimulator) Treatment with cholinergic or anticholinergic medication in the past month Pre-existing cardiac arrhythmia or presence of cardiac pacemaker/defibrillator History of dysautonomias History of vasovagal syncope Progressive neurological diseases other than epilepsy Women that are pregnant Cognitive or psychiatric deficit that in the investigator's judgment would interfere with the subject's ability to accurately complete study assessments

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: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: A change or titration in the current or frequency settings of the VNS therapy system.|The study treatment involves changing the output current or frequency of the default device settings in a FDA approved device for VNS therapy. The proposed frequency changes in this study are within the FDA approved output current and frequency levels.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in seizure frequency or duration via a routine seizure history used in clinical practice. |  | Following the 4 - week VNS treatment phase to the of the end of study. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in heart rate and blood pressure in response to upright tilt, deep breathing, Valsalva maneuver and a cold pressor test. |  | From pre VNS setting changes (baseline) to post VNS setting changes (end of study). | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vagus Nerve Stimulation (VNS), Neuromodulation, Autonomics