Percutaneous Inferior Cervical Sympathetic Block for Treatment of Refractory Ventricular Tachycardia

Study Overview
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Brief Summary
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The purpose of this research study is to examine the effect of percutaneous inferior cervical sympathetic block on life threatening abnormal heart rhythms called ventricular tachycardia or ventricular fibrillation that can lead to sudden cardiac death.

Official Title
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Percutaneous Inferior Cervical Sympathetic Block for Treatment of Refractory Ventricular Tachycardia

Conditions
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Ventricular Tachycardia

Intervention / Treatment
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* Procedure: Percutaneous inferior cervical sympathetic block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Appropriate ICD shock for ventricular tachycardia (VT) after at least one catheter ablation of VT procedure, OR appropriate ICD shock for VT but not a candidate for catheter ablation of VT (i.e. patients with presence polymorphic VT or ventricular fibrillation, LV thrombus, VT arising from an inaccessible myocardial location). Presence of structural heart disease as defined as EF ≤ 50%, presence of ventricular scar as detected by imaging modalities or electroanatomic mapping, hypertrophic cardiomyopathy, cardiac sarcoidosis, or arrhythmogenic right ventricular cardiomyopathy. Patient is taking at least one anti-arrhythmic drug or has documented intolerance or toxicity to at least one anti-arrhythmic drug. Age greater than 18 years old. Able and willing to comply with all pre- and follow-up testing and requirements. Provision of signed informed consent and stated willingness to comply with all study procedures for duration of the study. Exclusion Criteria: Active ongoing cardiac ischemia as assessed by: EKG, cardiac enzymes, symptoms, coronary angiography with evidence of significant epicardial coronary stenosis (>70%), or stress testing. (Note: positive troponin assay due to ICD shocks is not an exclusion criterion). Any medical or non-medical condition likely to prevent completion of trial. Contraindication to cardiac sympathetic denervation (i.e. single-lung ventilation, severe pulmonary disease, or severe pulmonary hypertension) or previous cardiac sympathetic denervation procedure. Left ventricular assist device or status post orthotopic heart transplantation Severe thrombocytopenia (platelets < 50,000) or coagulopathy (INR > 2.0) that is not due to medications or a reversible cause. Women who are pregnant (as evidenced by pregnancy test if pre-menopausal). Unable or unwilling to comply with protocol requirements. NYHA class IV heart failure symptoms. Known channelopathy such as long QT syndrome and catecholaminergic polymorphic VT. Presentation with slow VT (VT rate < 150 bpm).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Percutaneous inferior cervical sympathetic block<br>The procedure will be performed while the patient was awake and under fluoroscopic guidance. A total of 3 ml of 1% lidocaine will be infiltrated to anesthetize the skin and subcutaneous tissues down to the left common carotid artery. A 22 gauge × 3.5 inch BD™ Quincke spinal needle will be introduced at the level of the body of the sixth cervical vertebra, medial to the left common carotid artery. The needle will be advanced until it reached the junction between the body and transverse process of the sixth cervical vertebra. Contrast injection will be used to demonstrate the position of the needle anterior to the paravertebral muscles, with spread along the axis of the interfascial compartment (Figure 1). A total of 20 ml of 0.25% bupivacaine (Marcaine, Hospira, Lake Forest, IL) will be injected over 10 min through the needle. The effectiveness of sympathetic blockade will be confirmed by postprocedure development of ptosis and miosis in the left eye. | Procedure: Percutaneous inferior cervical sympathetic block<br>* The procedure will be performed while the patient was awake and under fluoroscopic guidance. A total of 3 ml of 1% lidocaine will be infiltrated to anesthetize the skin and subcutaneous tissues down to the left common carotid artery. A 22 gauge × 3.5 inch BD™ Quincke spinal needle will be introduced at the level of the body of the sixth cervical vertebra, medial to the left common carotid artery. The needle will be advanced until it reached the junction between the body and transverse process of the sixth cervical vertebra. Contrast injection will be used to demonstrate the position of the needle anterior to the paravertebral muscles, with spread along the axis of the interfascial compartment (Figure 1). A total of 20 ml of 0.25% bupivacaine (Marcaine, Hospira, Lake Forest, IL) will be injected over 10 min through the needle. The effectiveness of sympathetic blockade will be confirmed by postprocedure development of ptosis and miosis in the left eye.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Freedom from implantable cardioverter-defibrillator shock | Zero number of required cardioverter-defibrillator shocks in the patient's medical records | 3 months |