title: Outcomes of repeat catheter ablation using magnetic navigation or conventional ablation.
abstract: OBJECTIVE
  After initial catheter ablation, repeat procedures could be necessary. This study evaluates the efficacy of the magnetic navigation system (MNS) in repeat catheter ablation as compared with manual conventional techniques (MANs).
  
  
  RESULTS
  The results of 163 repeat ablation procedures were analysed. Ablations were performed either using MNS (n = 84) or conventional manual ablation (n = 79). Procedures were divided into four groups based on the technique used during the initial and repeat ablation procedure: MAN-MAN (n = 66), MAN-MNS (n = 31), MNS-MNS (n = 53), and MNS-MAN (n = 13). Three subgroups were analysed: supraventricular tachycardias (SVTs, n = 68), atrial fibrillation (AF, n = 67), and ventricular tachycardias (VT, n = 28). Recurrences were assessed during 19 ± 11 months follow-up. Overall, repeat procedures using MNS were successful in 89.0% as compared with 96.2% in the MAN group (P = ns). The overall recurrence rate was significantly lower using MNS (25.0 vs. 41.4%, P = 0.045). Acute success and recurrence rates for the MAN-MAN, MAN-MNS, MNS-MNS, and MNS-MAN groups were comparable. For the SVT subgroup a higher acute success rate was achieved using MAN (87.9 vs. 100.0%, P = 0.049). The use of MNS for SVT is associated with longer procedure times (205 ± 82 vs. 172 ± 69 min, P = 0.040). For AF procedure and fluoroscopy times were longer (257 ± 72 vs. 185 ± 64, P = 0.001; 59.5 ± 19.3 vs. 41.1 ± 18.3 min, P < 0.001). Less fluoroscopy was used for MNS-guided VT procedures (22.8 ± 14.7 vs. 41.2 ± 10.9, P = 0.011).
  
  
  CONCLUSIONS
  Our data suggest that overall MNS is comparable with MAN in acute success after repeat catheter ablation. However, MNS is related to fewer recurrences as compared with MAN.
authors.affiliation: Clinical Electrophysiology, Department of Cardiology, Erasmus MC, Postbus 2040, 3000 CA Rotterdam, `s Gravendijkwal 230, Kamer BD416, The Netherlands 
authors.forename: Ferdi
authors.initials: F
authors.lastname: Akca
authors.forename: Dominic A M J
authors.initials: DA
authors.lastname: Theuns
authors.forename: Lara Dabiri
authors.initials: LD
authors.lastname: Abkenari
authors.forename: Natasja M S
authors.initials: NM
authors.lastname: de Groot
authors.forename: Luc
authors.initials: L
authors.lastname: Jordaens
authors.forename: Tamas
authors.initials: T
authors.lastname: Szili-Torok
mesh_terms: D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D001281:Atrial Fibrillation / Q000601:surgery; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D015641:Radiography, Interventional; D012008:Recurrence; D012042:Registries; D012086:Reoperation; D025321:Surgery, Computer-Assisted / Q000009:adverse effects; D013617:Tachycardia, Supraventricular / Q000601:surgery; D017180:Tachycardia, Ventricular / Q000601:surgery; D016896:Treatment Outcome
keywords: Arrhythmia; Catheter ablation; Electrophysiology; Remote magnetic navigation; Repeat