title: Clinical study of the efficacy of a cooled-tip catheter ablation system for common atrial flutter.
abstract: BACKGROUND
  Radiofrequency catheter ablation (RF-CA) of common atrial flutter (AFL) requires the creation of a transmural incision to create a bidirectional conduction block in the cavotricuspid isthmus (ITH).
  
  
  RESULTS
  RF-CA of the ITH using a cooled-tip system was carried out in 40 patients. In the 'conventional' mode (CONV) of the system, RF energy was applied for 2 min with the temperature set at 60 degrees C and power of up to 50 W, and in the failed cases the 'cooled-tip' mode (COOL) was utilized at 45 degrees C with up to 30 W (with a 15 ml/min saline flow rate). Of the 40 patients, 29 crossed over from the CONV to the COOL after a failed ablation of the AFL. As a result, in all 40 patients a complete linear incision could be created with either the COOL or the CONV, resulting in the successful abolition of the AFL. Complete bi-directional block was successfully created in all patients. No significant side effects occurred.
  
  
  CONCLUSIONS
  The COOL was found to be more effective and just as safe as the CONV for AFL ablation, thus facilitating the rapid and complete elimination of the AFL.
authors.affiliation: Cardiovascular Center, Yokohama Red Cross Hospital, Japan. okishige@yo.rim.or.jp
authors.forename: Kaoru
authors.initials: K
authors.lastname: Okishige
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Aonuma
authors.forename: Yasuteru
authors.initials: Y
authors.lastname: Yamauchi
authors.forename: Kouji
authors.initials: K
authors.lastname: Azegami
authors.forename: Kou
authors.initials: K
authors.lastname: Suzuki
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Isobe
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Iesaka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001282:Atrial Flutter / Q000628:therapy*; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods; D003080:Cold Temperature; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013997:Time Factors; D016896:Treatment Outcome