title: Remote-controlled catheter ablation of accessory pathways: results from the magnetic laboratory.
abstract: OBJECTIVE
  This study evaluates feasibility, safety, and efficacy of magnetic remote-controlled accessory pathway (AP) ablation.
  
  
  RESULTS
  The novel magnetic navigation system (MNS) (Niobe, Stereotaxis) creates a steerable magnetic field (0.08 T) controlling the distal magnetic tip of an ablation catheter. In conjunction with a catheter advancer system (Cardiodrive, Stereotaxis) remote catheter ablation is enabled. Conventional electrophysiology study identified AP conduction in 59 patients (37 males, 36+/-14 years, 60 APs). First generation 1-magnet tip (1-M) (group I, n=18), second generation bipolar 3-magnet tip (3-M) (group II, n=27), and third generation quadripolar 3-magnet tip catheters (3-M quad.) (group III, n=14) were used for magnetic remote-controlled ablation. Successful AP ablation was achieved in 67% (group I), 85% (group II), and 92% (group III). A significant decrease of median [IQR: Q1-Q3] fluoroscopy time and dosage was observed: 21.2 [12.1-33.8] min, 1110 [395-3234] microGym2 (group I); 6.5 [4.4-15.4] min, 290 [129-489] microGym2 (group II), and 4.9 [3.4-8.0] min, 129 [74-270] microGym2 (group III). Mean procedure time (217+/-67 min; 182+/-68 min, and 172+/-90 min) significantly decreased in group III. Median number [Q1-Q3] of radiofrequency current applications in groups I, II, and III was 4 [2-9], 4 [2-6], and 2 [2-4], respectively. No complications occurred.
  
  
  CONCLUSIONS
  Remote AP ablation is safe and feasible using the novel MNS. Introduction of the 3-magnet quadripolar ablation catheter significantly improved the efficacy of the procedure.
authors.affiliation: Department of Cardiology, Asklepios Klinik St Georg Hospital, Lohmuehlenstr. 5, Hamburg 20099, Germany. jongichun@t-online.de
authors.forename: Julian Kyoung-Ryul
authors.initials: JK
authors.lastname: Chun
authors.forename: Sabine
authors.initials: S
authors.lastname: Ernst
authors.forename: Shibu
authors.initials: S
authors.lastname: Matthews
authors.forename: Boris
authors.initials: B
authors.lastname: Schmidt
authors.forename: Dietmar
authors.initials: D
authors.lastname: Bansch
authors.forename: Sigrid
authors.initials: S
authors.lastname: Boczor
authors.forename: Amaar
authors.initials: A
authors.lastname: Ujeyl
authors.forename: Matthias
authors.initials: M
authors.lastname: Antz
authors.forename: Feifan
authors.initials: F
authors.lastname: Ouyang
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Kuck
mesh_terms: D000328:Adult; D017115:Catheter Ablation / Q000379:methods*; D004594:Electrophysiology; D005240:Feasibility Studies; D005260:Female; D005471:Fluoroscopy; D005500:Follow-Up Studies; D006801:Humans; D008280:Magnetics; D008297:Male; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome