title: Prospective randomized comparison of a steerable versus a non-steerable sheath for typical atrial flutter ablation.
abstract: OBJECTIVE
  Although cavotricuspid isthmus (CTI) ablation can cure typical atrial flutter (AFL), it might be difficult to achieve a bidirectional conduction block in the isthmus in some patients. We investigated the usefulness of a steerable sheath for CTI ablation in patients with typical AFL or atrial fibrillation.
  
  
  RESULTS
  A total of 40 consecutive patients (36 males; mean age 55.2 +/- 10.0 years) undergoing CTI ablation were randomized to one of the following two groups: group S (using a steerable long sheath) or group NS (using a non-steerable long sheath). Ablation was performed using an 8 mm tip catheter. The anatomy of the CTI was evaluated by a dual-source computed tomography scan prior to the procedure. The procedural endpoint was the achievement of a bidirectional isthmus conduction block. Bidirectional block in the CTI was achieved in all patients with 485.3 +/- 416.4 s of radiofrequency (RF) application. The CTI anatomy, including the length, depth, and morphology, was similar between the two groups. The duration and total amount of RF energy delivery were significantly shorter and smaller in group S than in group NS (310 +/- 193 vs. 661 +/- 504 s, P = 0.006, and 12,197 +/- 7306 vs. 26,906 +/- 21,238 J, P = 0.006, respectively).
  
  
  CONCLUSIONS
  The use of a steerable sheath reduced the time and amount of energy needed to achieve a bidirectional conduction block in the CTI. For patients in whom the establishment of a conduction block is difficult, a steerable sheath should be considered as a therapeutic option for typical AFL ablation.
authors.affiliation: Department of Cardiology, Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan. mattsuu@tc4.so-net.ne.jp
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Matsuo
authors.forename: Teiichi
authors.initials: T
authors.lastname: Yamane
authors.forename: Michifumi
authors.initials: M
authors.lastname: Tokuda
authors.forename: Taro
authors.initials: T
authors.lastname: Date
authors.forename: Mika
authors.initials: M
authors.lastname: Hioki
authors.forename: Ryohsuke
authors.initials: R
authors.lastname: Narui
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ito
authors.forename: Seigo
authors.initials: S
authors.lastname: Yamashita
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Hama
authors.forename: Tokiko
authors.initials: T
authors.lastname: Nakane
authors.forename: Keiichi
authors.initials: K
authors.lastname: Inada
authors.forename: Kenri
authors.initials: K
authors.lastname: Shibayama
authors.forename: Satoru
authors.initials: S
authors.lastname: Miyanaga
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoshida
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Miyazaki
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Abe
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Sugimoto
authors.forename: Ikuo
authors.initials: I
authors.lastname: Taniguchi
authors.forename: Michihiro
authors.initials: M
authors.lastname: Yoshimura
mesh_terms: D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000601:surgery; D001282:Atrial Flutter / Q000000981:diagnostic imaging / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed; D014261:Tricuspid Valve / Q000000981:diagnostic imaging / Q000601:surgery*