title: Vagal response during pulmonary vein isolation: Re-recognized its characteristics and implications in lone paroxysmal atrial fibrillation.
abstract: BACKGROUND
  The role of autonomic innervation around the pulmonary vein (PV) antrum in the genesis of atrial fibrillation (AF) has been demonstrated but the characteristics of radiofrequency induced vagal response (VR) in the PV antrum and its clinical impact on pulmonary vein isolation (PVI) for paroxysmal AF need to be further elucidated.
  
  
  METHODS
  Of 995 consecutive patients with symptomatic paroxysmal AF undergoing PVI at a single center over a 2-year period, 516 met exclusion criteria and the remaining 479 patients, 156 positive VR (PVR) and 323 negative VR (NVR), underwent 12-month follow-up. The primary endpoint was freedom from AF or other sustained atrial tachycardia (AT), verified by monthly visits and electrocardiographic monitoring. The frequency-domain analysis was performed to evaluate the autonomic activity before and after the procedure.
  
  
  RESULTS
  VR was most commonly elicited during PVI at the LSPV roof (65.4%) and anterior RSPV (44.9%, with a >5s sinus pause in 37/70 [52.8%] cases). Compared with the NVR group, ablation was associated with reduced AF recurrence at 12 months in the PVR (hazard ratio: 0.53, 95% confidence interval: 0.22-0.89). Furthermore, the PVR group showed a significantly abbreviated AF cycle length at the left PV, and significantly lower HF and LF parameters with stable LF/HF ratio during follow-up.
  
  
  CONCLUSIONS
  Complete elimination of vagal response, most commonly elicited by radiofrequency application around the roof of LSPV and anterior RSPV, appeared associated with reduced 12-month recurrence of AF and with marked heart rate variability changes consistent with autonomic nervous withdrawal.
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China. Electronic address: heartqm@sina.com.
authors.forename: Mu
authors.initials: M
authors.lastname: Qin
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China. Electronic address: heartlx@sina.com.
authors.forename: Xu
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Jiang
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Shao-Hui
authors.initials: SH
authors.lastname: Wu
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Zhang
authors.affiliation: Department of Medicine and Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
authors.forename: Sunny
authors.initials: S
authors.lastname: Po
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000503:physiopathology* / Q000601:surgery; D017115:Catheter Ablation / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011667:Pulmonary Veins / Q000294:innervation / Q000503:physiopathology* / Q000601:surgery; D014630:Vagus Nerve / Q000503:physiopathology* / Q000601:surgery
keywords: Atrial fibrillation; Autonomic nervous system; Pulmonary vein isolation; Vagal response