title: High-density mapping of spontaneous pulmonary vein activity initiating atrial fibrillation in humans.
abstract: BACKGROUND
  High-density three-dimensional (3D) mapping of the pulmonary vein (PV)-left atrial (LA) junction was performed to characterize spontaneous PV activity in humans.
  
  
  RESULTS
  The activation patterns of ectopic beats and of the initial 2 seconds of atrial fibrillation (AF) from the PVs were analyzed using a 64-poles basket catheter. A focal mechanism was defined as a discrete site of early and centrifugal activation. Continuous activity was considered as an activation covering > or = 80% of the tachycardia beat-to-beat cycle length within the mapping field. In 35 patients, 123 spontaneous focal ectopic beats that did not induce AF and 95 that did induce AF were mapped. The mean coupling interval of ectopic discharges not inducing AF was 281 +/- 70 msec versus 236 +/- 90 msec for ectopies initiating AF (P < or = 0.01). The first ectopic activity of all 218 arrhythmogenic events showed exclusively a focal mechanism. During the 95 episodes of AF initiation, one or two ectopic beats from the PVs initiated AF in the LA in 39%, a stable focal tachycardia was recorded in 14%, continuous activity with important changes in cycle length (35 +/- 15 msec) suggestive of decremental or fibrillatory conduction was found in 18%, and in 29% the activation pattern could not be classified. No stable and sustained reentrant circuit could be identified by our mapping tool in the PV-LA junction.
  
  
  CONCLUSIONS
  Arrhythmogenic activity from PVs in humans is predominantly due to discrete focal activity.
authors.affiliation: Rhythmologie, Herz-Zentrum, Bad Krozingen, Germany. thomas.arentz@herzzentrum.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Arentz
authors.forename: Laurent
authors.initials: L
authors.lastname: Haegeli
authors.forename: Prashanthan
authors.initials: P
authors.lastname: Sanders
authors.forename: Reinhold
authors.initials: R
authors.lastname: Weber
authors.forename: Franz Josef
authors.initials: FJ
authors.lastname: Neumann
authors.forename: Dietrich
authors.initials: D
authors.lastname: Kalusche
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000503:physiopathology; D006328:Cardiac Catheterization; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000503:physiopathology*; D012720:Severity of Illness Index