title: Characterization of conduction recovery across left atrial linear lesions in patients with paroxysmal and persistent atrial fibrillation.
abstract: BACKGROUND
  Left atrial (LA) linear lesions are effective in substrate modification for atrial fibrillation (AF). However, achievement of complete conduction block remains challenging and conduction recovery is commonly observed. The aim of the study was to investigate the localization of gap sites of recovered LA linear lesions.
  
  
  RESULTS
  Forty-eight patients with paroxysmal (n = 26) and persistent/permanent (n = 22) AF underwent repeat ablation after pulmonary vein (PV) isolation and LA linear ablation at the LA roof and/or mitral isthmus due to recurrences of AF or flutter. In 35 patients, conduction through the mitral isthmus line (ML) had recovered whereas roof-line recovery was observed in 30 patients. The gaps within the ML were distributed to the junction between left inferior PV and left atrial appendage in 66%, the middle part of the ML in 20%, and in 8% to the endocardial aspect of the ML while only 6% of lines showed an epicardial site of recovery. The RL predominantly recovered close to the right superior PV (54%) and less frequently in the mid roof or close to the left PV (both 23%). Reablation of lines required significantly shorter RF durations (ML: 7.24 +/- 5.55 minutes vs 24.08 +/- 9.38 minutes, RL: 4.24 +/- 2.34 minutes vs 11.54 +/- 6.49 minutes; P = 0.0001). Patients with persistent/permanent AF demonstrated a significantly longer conduction delay circumventing the complete lines than patients with paroxysmal AF (228 +/- 77 ms vs 164 +/- 36 ms, P = 0.001).
  
  
  CONCLUSIONS
  Gaps in recovered LA lines were predominantly located close to the PVs where catheter stability is often difficult to achieve. Shorter RF durations are required for reablation of recovered linear lesions. Conduction times around complete LA lines are significantly longer in patients with persistent/permanent AF as compared to patients with paroxysmal AF.
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque and the Université Victor Segalen Bordeaux II, Bordeaux, France. rostock@uke.uni-hamburg.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Rostock
authors.forename: Mark D
authors.initials: MD
authors.lastname: O'Neill
authors.forename: Prashanthan
authors.initials: P
authors.lastname: Sanders
authors.forename: Martin
authors.initials: M
authors.lastname: Rotter
authors.forename: Pierre
authors.initials: P
authors.lastname: Jaïs
authors.forename: Mélèze
authors.initials: M
authors.lastname: Hocini
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Fréderic
authors.initials: F
authors.lastname: Sacher
authors.forename: Anders
authors.initials: A
authors.lastname: Jönsson
authors.forename: Li-Fern
authors.initials: LF
authors.lastname: Hsu
authors.forename: Jacques
authors.initials: J
authors.lastname: Clémenty
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D017115:Catheter Ablation; D002908:Chronic Disease; D015331:Cohort Studies; D005260:Female; D006325:Heart Atria / Q000503:physiopathology* / Q000601:surgery*; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020127:Recovery of Function; D055502:Secondary Prevention; D016896:Treatment Outcome