A Study of Stellate Ganglion Block for Prevention of Atrial Fibrillation

Study Overview
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Brief Summary
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The purpose of this study is to test if a nerve block procedure called a stellate ganglion block can help decrease the chance of atrial fibrillation after surgery. Atrial fibrillation is the abnormal, fast beating of the upper chambers of the heart. Stellate ganglion blockade has shown to decrease other types of abnormal heart rhythms as well as decrease the chance of atrial fibrillation.

Detailed Description
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The investigator hypothesizes that stellate ganglion blockade with local anesthetic performed prior to cardiac surgery will reduce the incidence and duration of postoperative atrial fibrillation (POAF). Specific Aim 1: Determine the incidence of POAF in patients receiving pre-surgical stellate ganglion blockade with local anesthetic versus saline placebo within one week of surgery or during hospitalization if discharged prior to one week. Specific Aim 2: Determine the duration of POAF in patients receiving pre-surgical stellate ganglion blockade with local anesthetic versus saline placebo within one week of surgery or during hospitalization if discharged prior to one week. Specific Aim 3: Determine the success rate of the block as evaluated by ipsilateral hand temperature change and skin sympathetic nerve activity (SKNA).

Official Title
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Stellate Ganglion Blockade for the Prevention of Atrial Fibrillation After Cardiac Surgery: A Randomized Placebo-Controlled Trial

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Procedure: Stellate ganglion block
* Drug: Bupivacaine
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient presenting for cardiac surgery at the Mayo Clinic in Rochester, Minnesota. Patients scheduled to undergo mitral or aortic valve surgery with or without coronary artery bypass grafting. Exclusion Criteria: Patients with a history of permanent atrial fibrillation, left or right ventricular assist device implantation or explantation. Patients with procedures not requiring cardiopulmonary bypass. Patients with procedures requiring deep hypothermic circulatory arrest. Patients with active infection or sepsis. Pre-operative immunosuppressive medication use (including steroid use). Pre-operative anti-arrhythmic medication use (aside from beta-blockers). Patients with Immunodeficiency syndrome. Patients with known neurologic disorder. Patients requiring left internal jugular central line placement. Performance of Maze procedures or left atrial appendage ligation procedures will not exclude patients from potential enrollment as atrial fibrillation still occurs postoperatively while the scarring from the Maze procedure forms.

Ages Eligible for Study
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Minimum Age: 60 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Stellate ganglion block with local anesthetic<br>Subjects will receive a single injection of bupivacaine in a stellate ganglion block | Procedure: Stellate ganglion block<br>* Ultrasound guided injection into the stellate ganglion performed in the right side of the neck in a sterile fashion.<br>Drug: Bupivacaine<br>* 10 mL of 0.5% without epinephrine injected in the plane of the right stellate ganglion<br>|
| Sham Comparator: Stellate ganglion block with saline placebo<br>Subjects will receive a single injection of saline in a stellate ganglion block | Procedure: Stellate ganglion block<br>* Ultrasound guided injection into the stellate ganglion performed in the right side of the neck in a sterile fashion.<br>Drug: Placebo<br>* 10 mL of saline injected in the plane of the right stellate ganglion<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of atrial fibrillation | Percentage of subjects to experience postoperative atrial fibrillation (POAF) | Within one week of surgery or during hospitalization if discharged prior to one week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration of atrial fibrillation | Duration of postoperative atrial fibrillation (POAF) | Within one week of surgery or during hospitalization if discharged prior to one week | 
| Skin Sympathetic Nerve Activity | Measurement of difference in skin sympathetic nerve activity following block | 10-30 minute following performance of nerve block |