title: Changes in atrial fibrillation cycle length and inducibility during catheter ablation and their relation to outcome.
abstract: BACKGROUND
  The modification of atrial fibrillation cycle length (AFCL) during catheter ablation in humans has not been evaluated.
  
  
  RESULTS
  Seventy patients undergoing ablation of prolonged episodes of AF were randomized to pulmonary vein (PV) isolation or additional ablation of the mitral isthmus. Mean AFCL was determined at a distance from the ablated area (coronary sinus) at the following intervals: before ablation, after 2- and 4-PV isolations, and after linear ablation. Inducibility of sustained AF (> or =10 minutes) was determined before and after ablation. Spontaneous sustained AF (715+/-845 minutes) was present in 30 patients and induced in 26 (AFCL, 186+/-19 ms). PV isolation terminated AF in 75%, with the number of PVs requiring isolation before termination increasing with AF duration (P=0.018). PV isolation resulted in progressive or abrupt AFCL prolongation to various extents, depending on the PV: to 214+/-24 ms (P<0.0001) when AF terminated and to 194+/-19 ms (P=0.002) when AF persisted. The increase in AFCL (30+/-17 versus 14+/-11 ms; P=0.005) and the decrease in fragmentation (30.0+/-26.8% to 10.3+/-14.5%; P<0.0001) were significantly greater in patients with AF termination. Linear ablation prolonged AFCL, with a greater prolongation in patients with AF termination (44+/-13 versus 22+/-23 ms; P=0.08). Sustained AF was noninducible in 57% after PV isolation and in 77% after linear ablation. At 7+/-3 months, 74% with PV isolation and 83% with linear ablation were arrhythmia free without antiarrhythmics, which was significantly associated with noninducibility (P=0.03) with a recurrence rate of 38% and 13% in patients with and without inducibility, respectively.
  
  
  CONCLUSIONS
  AF ablation results in a decline in AF frequency, with a magnitude correlating with termination of AF and prevention of inducibility that is predictive of subsequent clinical outcome.
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, Avenue de Magellan, 33604 Bordeaux, France. jacques.clementy@pu.u-bordeaux2.fr
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.forename: Prashanthan
authors.initials: P
authors.lastname: Sanders
authors.forename: Mélèze
authors.initials: M
authors.lastname: Hocini
authors.forename: Li-Fern
authors.initials: LF
authors.lastname: Hsu
authors.forename: Dipen C
authors.initials: DC
authors.lastname: Shah
authors.forename: Christophe
authors.initials: C
authors.lastname: Scavée
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Martin
authors.initials: M
authors.lastname: Rotter
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Pasquié
authors.forename: Stéphane
authors.initials: S
authors.lastname: Garrigue
authors.forename: Jacques
authors.initials: J
authors.lastname: Clémenty
authors.forename: Pierre
authors.initials: P
authors.lastname: Jaïs
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D001282:Atrial Flutter / Q000209:etiology / Q000503:physiopathology; D017115:Catheter Ablation; D018572:Disease-Free Survival; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000503:physiopathology / Q000601:surgery*; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome; D014261:Tricuspid Valve / Q000503:physiopathology / Q000601:surgery