Catheter-based renal sympathetic denervation significantly inhibits atrial fibrillation induced by electrical stimulation of the left stellate ganglion and rapid atrial pacing.
BACKGROUND
Sympathetic activity involves the pathogenesis of atrial fibrillation (AF). Renal sympathetic denervation (RSD) decreases sympathetic renal afferent nerve activity, leading to decreased central sympathetic drive. The aim of this study was to identify the effects of RSD on AF inducibility induced by hyper-sympathetic activity in a canine model.


METHODS
To establish a hyper-sympathetic tone canine model of AF, sixteen dogs were subjected to stimulation of left stellate ganglion (LSG) and rapid atrial pacing (RAP) for 3 hours. Then animals in the RSD group (n = 8) underwent radiofrequency ablation of the renal sympathetic nerve. The control group (n = 8) underwent the same procedure except for ablation. AF inducibility, effective refractory period (ERP), ERP dispersion, heart rate variability and plasma norepinephrine levels were measured at baseline, after stimulation and after ablation.


RESULTS
LSG stimulation combined RAP significantly induced higher AF induction rate, shorter ERP, larger ERP dispersion at all sites examined and higher plasma norepinephrine levels (P<0.05 in all values), compared to baseline. The increased AF induction rate, shortened ERP, increased ERP dispersion and elevated plasma norepinephrine levels can be almost reversed by RSD, compared to the control group (P<0.05). LSG stimulation combined RAP markedly shortened RR-interval and standard deviation of all RR-intervals (SDNN), Low-frequency (LF), high-frequency (HF) and LF/HF ratio (P<0.05). These changes can be reversed by RSD, compared to the control group (P<0.05).


CONCLUSIONS
RSD significantly reduced AF inducibility and reversed the atrial electrophysiological changes induced by hyper-sympathetic activity.
Department of Cardiovascular Diseases, The 6th People's Hospital affiliated to Shanghai Jiaotong University, Shanghai, China.
Yuemei
Y
Hou
Jialu
J
Hu
Sunny S
SS
Po
Huan
H
Wang
Ling
L
Zhang
Feng
F
Zhang
Kun
K
Wang
Qina
Q
Zhou
D000818:Animals; D001281:Atrial Fibrillation / Q000097:blood / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D002304:Cardiac Pacing, Artificial; D017115:Catheter Ablation; D004285:Dogs; D004558:Electric Stimulation / Q000009:adverse effects; D006325:Heart Atria / Q000294:innervation / Q000503:physiopathology*; D006339:Heart Rate; D007668:Kidney / Q000294:innervation; D009638:Norepinephrine / Q000097:blood; D013233:Stellate Ganglion / Q000293:injuries* / Q000503:physiopathology; D013562:Sympathectomy
D009638:Norepinephrine