title: Recurrence of conduction following radiofrequency catheter ablation procedures: relationship to ablation target and electrode temperature. The Atakr Multicenter Investigators Group.
abstract: BACKGROUND
  More than 1 in 10 patients may develop recurrence of conduction after undergoing a successful radiofrequency catheter ablation procedure. The physiologic basis for recurrence following successful ablation procedures remains uncertain. The purpose of this study was to evaluate the role of electrode temperature as a predictor of recurrence following radiofrequency catheter ablation procedures.
  
  
  RESULTS
  The subjects of this study were 538 patients who underwent a successful attempt at radiofrequency catheter ablation of AV nodal reentrant tachycardia, an accessory pathway, and/or the AV junction. Patients were followed for a mean of 215 +/- 138 days. Conduction recurred in 35 (6.5%) of the 538 patients. Recurrence of conduction occurred in 25 (9.3%) of 270 patients undergoing ablation of an accessory pathway, 7 (3.5%) of 201 patients undergoing ablation of AV nodal reentrant tachycardia, and in 3 (4.5%) of 67 patients undergoing ablation of the AV junction. The electrode temperature achieved at successful sites associated with recurrence was not different from the temperature achieved at successful sites without recurrence (61.1 +/- 8.9 vs 61.6 +/- 9.1; P = 0.8). The likelihood of developing a recurrence was higher following ablation of accessory pathways than following ablation of AV nodal reentrant tachycardia or the AV junction (P = 0.03). Patients experiencing a recurrence following ablation of an accessory pathway had longer procedure durations (P = 0.0001). Ablation of left free-wall pathways was associated with a lower incidence of recurrence as compared with all other locations (P = 0.008).
  
  
  CONCLUSIONS
  The results of this study suggest that electrode temperature at the successful ablation site cannot be used to identify patients at highest risk of recurrence.
authors.affiliation: Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: H
authors.initials: H
authors.lastname: Calkins
authors.forename: E
authors.initials: E
authors.lastname: Prystowsky
authors.forename: R D
authors.initials: RD
authors.lastname: Berger
authors.forename: J P
authors.initials: JP
authors.lastname: Saul
authors.forename: L S
authors.initials: LS
authors.lastname: Klein
authors.forename: L B
authors.initials: LB
authors.lastname: Liem
authors.forename: S K
authors.initials: SK
authors.lastname: Huang
authors.forename: P
authors.initials: P
authors.lastname: Gillette
authors.forename: P
authors.initials: P
authors.lastname: Yong
authors.forename: M
authors.initials: M
authors.lastname: Carlson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation; D002648:Child; D002675:Child, Preschool; D004566:Electrodes; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000503:physiopathology / Q000601:surgery; D013696:Temperature