title: Endocardial autonomic denervation of the left atrium to treat vasovagal syncope: an early experience in humans.
abstract: BACKGROUND
  Vasovagal syncope (VVS) is the most common cause of recurrent syncope that can be debilitating despite optimal conventional therapy. The aim of this study was to evaluate the feasibility and efficacy of selective endocardial autonomic denervation in left atrium (LA) as an alternative treatment strategy in patients with highly symptomatic VVS.
  
  
  RESULTS
  Ten consecutive patients (mean age, 50.4±6.4 years; 7 women) with a medium of 3.5 (range, 2-20) recurrent episodes of VVS during the preceding year and positive head-up tilt testing in whom standard therapies were ineffective or poorly tolerated were enrolled. Ganglionated plexi (GP) in the LA, identified by high-frequency stimulation, was targeted by radiofrequency catheter ablation. The patients were then followed up at 3, 6, 12, 24, and 36 months, including repeated head-up tilt testing and Holter at 3 and 12 months. Radiofrequency energy was applied at the left superior GP in 10 patients, right anterior GP in 5, and left inferior GP in 3, using an 8-mm ablation catheter. Vagal response, defined as transient ventricular asystole, atrioventricular block, or an increase in R-R interval by 50%, was observed during ablation in all GP sites. The end point of procedure was the inhibition of the vagal response at target sites. At 30±16 (range, 13-55) months of follow-up, no patient had any recurrence of syncope and all patients had significant improvement in symptoms, but 5 of 10 patients reported transient prodromes. No complications occurred.
  
  
  CONCLUSIONS
  Comprehensive endocardial autonomic denervation of the LA demonstrates the feasibility of treating VVS in medium-term follow-up.
authors.affiliation: Clinical Electrophysiological Laboratory and Arrhythmia Center, Fuwai Hospital and Cardiovascular Institute, Peking Union Medical College (PUMC)–Chinese Academy of Medical Sciences (CAMS), Beijing, China. ianyao@263.net.cn
authors.forename: Yan
authors.initials: Y
authors.lastname: Yao
authors.forename: Rui
authors.initials: R
authors.lastname: Shi
authors.forename: Tom
authors.initials: T
authors.lastname: Wong
authors.forename: Lihui
authors.initials: L
authors.lastname: Zheng
authors.forename: Wensheng
authors.initials: W
authors.lastname: Chen
authors.forename: Long
authors.initials: L
authors.lastname: Yang
authors.forename: Wen
authors.initials: W
authors.lastname: Huang
authors.forename: Jingru
authors.initials: J
authors.lastname: Bao
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
mesh_terms: D000328:Adult; D017763:Autonomic Denervation / Q000379:methods*; D017115:Catheter Ablation; D004699:Endocardium / Q000294:innervation*; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000294:innervation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012189:Retrospective Studies; D019462:Syncope, Vasovagal / Q000517:prevention & control / Q000601:surgery*; D016896:Treatment Outcome