title: Intrinsic cardiac autonomic stimulation induces pulmonary vein ectopy and triggers atrial fibrillation in humans.
abstract: BACKGROUND
  The induction of atrial fibrillation (AF) by pulmonary vein (PV) ectopy is well described. The triggers for these PV ectopy are not so well understood. The intrinsic cardiac autonomic nervous system (ANS) has been suggested as a potential upstream regulator that may cause PV ectopy and atrial fibrillation (AF). We hypothesized that activation of the ANS by high frequency stimulation (HFS) of atrial ganglionated plexi (GP) can initiate PV ectopy.
  
  
  RESULTS
  During sinus rhythm in 12 patients undergoing ablation for paroxysmal AF, short bursts of HFS, synchronized to the local atrial refractory period, were delivered at presumed GP sites. Electrograms were recorded from catheters placed in the PV, coronary sinus (CS) and high right atrium (HRA). A total of 112 episodes of HFS were recorded, producing ectopic activity in 91 of 112 (81%) episodes. Of these 91 episodes, there were 46 episodes of isolated single ectopic beats, 5 episodes of double ectopic responses, 24 episodes of ectopy/tachycardia lasting <30 s, and 16 episodes of AF lasting >30 s. In 63 of 91 episodes, the PV catheter was placed adjacent to the stimulated GP, resulting in ectopy recorded earliest in the PV catheter in 48 of 63 (76%) episodes. In one patient, reproducible ectopy was shown to occur following AV nodal conduction delay in response to HFS. Without HFS, neither AV nodal conduction delay nor ectopy occurred.
  
  
  CONCLUSIONS
  This study has demonstrated a direct link between activation of the intrinsic cardiac autonomic nervous system and pulmonary vein ectopy in humans.
authors.affiliation: Cardiology Department, Imperial College Healthcare NHS Trust, St. Mary's Hospital, Praed Street, London, UK. pblim@imperial.ac.uk
authors.forename: Phang Boon
authors.initials: PB
authors.lastname: Lim
authors.forename: Louisa C
authors.initials: LC
authors.lastname: Malcolme-Lawes
authors.forename: Thomas
authors.initials: T
authors.lastname: Stuber
authors.forename: Ian
authors.initials: I
authors.lastname: Wright
authors.forename: Darrel P
authors.initials: DP
authors.lastname: Francis
authors.forename: D Wyn
authors.initials: DW
authors.lastname: Davies
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Peters
authors.forename: Prapa
authors.initials: P
authors.lastname: Kanagaratnam
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D001341:Autonomic Nervous System / Q000503:physiopathology*; D005117:Cardiac Complexes, Premature / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000503:physiopathology*