title: Impact of pre-existent areas of complex fractionated atrial electrograms on outcome after pulmonary vein isolation.
abstract: BACKGROUND
  Atrial fibrillation (AF) drivers outside pulmonary veins (PV) may account for failure after PV isolation. The aim of this study was to characterize pre-existent areas of complex fractionated atrial electrograms (CFAEs) recorded in right atrium (RA) and in coronary sinus (CS) during catheter-based PV isolation and to assess their relation to outcome.
  
  
  RESULTS
  With a tricuspid annulus and CS mapping, CFAEs were retrospectively identified in consecutive patients who underwent PV isolation. Of 224 patients, 161 were found to have CFAEs (81%). No clinical variable was found to be predictive of CFAEs presence. By Kaplan-Meier analysis, following a median follow-up of 23.7 months after a single ablation procedure, 62.8% of patients in the CFAEs+ group and 85.4% of those in the CFAEs- group were free from recurrent atrial tachyarrhythmias (p=0.013). Multivariable Cox regression analysis showed that CFAEs evidence was an independent predictor of recurrence (p=0.007).
  
  
  CONCLUSIONS
  Pre-existent CFAEs, that can be easily identified in RA and CS during PV isolation, are a powerful independent predictor for AF recurrence. This finding may be helpful for refining AF ablation strategies.
authors.affiliation: Department of Internal Medicine, Division of Cardiology, Policlinico Universitario Tor Vergata, Viale Oxford, 81, 00133 Roma, Italy. forleo@tiscali.it
authors.forename: Giovanni B
authors.initials: GB
authors.lastname: Forleo
authors.forename: Massimo
authors.initials: M
authors.lastname: Mantica
authors.forename: Lucia
authors.initials: L
authors.lastname: De Luca
authors.forename: Antonio
authors.initials: A
authors.lastname: Dello Russo
authors.forename: Michela
authors.initials: M
authors.lastname: Casella
authors.forename: Luca
authors.initials: L
authors.lastname: Santini
authors.forename: Gemma
authors.initials: G
authors.lastname: Pelargonio
authors.forename: Francesco
authors.initials: F
authors.lastname: Romeo
authors.forename: Claudio
authors.initials: C
authors.lastname: Tondo
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000601:surgery*; D017115:Catheter Ablation; D054326:Coronary Sinus / Q000503:physiopathology / Q000601:surgery; D003430:Cross-Sectional Studies; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006325:Heart Atria / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D012189:Retrospective Studies; D016896:Treatment Outcome