Low-level transcutaneous electrical vagus nerve stimulation suppresses atrial fibrillation.
BACKGROUND
Transcutaneous low-level tragus electrical stimulation (LLTS) suppresses atrial fibrillation (AF) in canines.


OBJECTIVE
This study examined the antiarrhythmic and anti-inflammatory effects of LLTS in humans.


METHODS
Patients with paroxysmal AF who presented for AF ablation were randomized to either 1 h of LLTS (n = 20) or sham control (n = 20). Attaching a flat metal clip onto the tragus produced LLTS (20 Hz) in the right ear (50% lower than the voltage slowing the sinus rate). Under general anesthesia, AF was induced by burst atrial pacing at baseline and after 1 h of LLTS or sham treatment. Blood samples from the coronary sinus and the femoral vein were collected at those time points and then analyzed for inflammatory cytokines, including tumor necrosis factor alpha and C-reactive protein, using a multiplex immunoassay.


RESULTS
There were no differences in baseline characteristics between the 2 groups. Pacing-induced AF duration decreased significantly by 6.3 ± 1.9 min compared with baseline in the LLTS group, but not in the control subjects (p = 0.002 for comparison between groups). AF cycle length increased significantly from baseline by 28.8 ± 6.5 ms in the LLTS group, but not in control subjects (p = 0.0002 for comparison between groups). Systemic (femoral vein) but not coronary sinus tumor necrosis factor (TNF)-alpha and C-reactive protein levels decreased significantly only in the LLTS group.


CONCLUSIONS
LLTS suppresses AF and decreases inflammatory cytokines in patients with paroxysmal AF. Our results support the emerging paradigm of neuromodulation to treat AF.
Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.
Stavros
S
Stavrakis
Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.
Mary Beth
MB
Humphrey
Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.
Benjamin J
BJ
Scherlag
Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.
Yanqing
Y
Hu
Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.
Warren M
WM
Jackman
Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.
Hiroshi
H
Nakagawa
Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.
Deborah
D
Lockwood
Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.
Ralph
R
Lazzara
Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma. Electronic address: sunny-po@ouhsc.edu.
Sunny S
SS
Po
D001281:Atrial Fibrillation / Q000097:blood / Q000628:therapy*; D002097:C-Reactive Protein / Q000032:analysis; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D004561:Transcutaneous Electric Nerve Stimulation / Q000379:methods*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D055536:Vagus Nerve Stimulation / Q000379:methods*
D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein
atrial fibrillation; autonomic nervous system; inflammation; neuromodulation