title: Six-month follow-up of isthmus-dependent right atrial flutter ablation using a remote magnetic catheter navigation system: a case-control study.
abstract: OBJECTIVE
  The objective of this study was to compare results between the magnetic navigation system (MNS) and conventional catheter ablation of cavo-tricuspid isthmus (CTI)-dependent right atrial flutter (AFL) in a case control study.
  
  
  BACKGROUND
  A remote MNS has been used for ablation of various arrhythmias including CTI-dependent AFL but comparative results between MNS and conventional ablation are not available.
  
  
  METHODS
  Between May and September 2007, a total of 51 consecutive patients (45 men, mean age 65.4 +/- 9.4 years) had undergone catheter ablation for CTI-dependent AFL. The catheter ablation (70 degrees C, 70 W, 90 s) was performed with either an 8-mm-tip magnetic catheter using MNS (case group, n = 26, 23 men, mean age 64.6 +/- 9.6 y) or a conventional 8-mm catheter (case group, n = 25, 22 men, mean age 65.4 +/- 9.1 y). Acute procedural success was defined as complete bidirectional isthmus block and success at six months was defined as absence of AFL during the six months follow-up.
  
  
  RESULTS
  With respect to baseline characteristics there were no differences between the two groups. The procedure time in MNS and conventional group was [median (range)] 53 (30-130) min and 45 (30-100) min, respectively (P = 0.12). Acute success was achieved by MNS and conventional ablation in 25/26 (96.2%) and 25/25 (100%) of patients, respectively (P = 0.53). During the six months of follow-up 4 patients, 2 in each group, experienced recurrence (P = 0.90). No major complication occurred during the procedure. Charring on the catheter tip occurred in 5 patients (19.2%) in MNS and none of the patients in the control group (P <0.05).
  
  
  CONCLUSIONS
  This case-control study demonstrated the acute and mid-term efficacy and safety of catheter ablation by MNS for CTI-dependent AFL, similar to rates achieved by conventional radiofrequency catheter ablation.
authors.affiliation: Department of Electrophysiology, University of Leipzig, Heart Center, Leipzig, Germany.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huo
authors.forename: Gerhard
authors.initials: G
authors.lastname: Hindricks
authors.forename: Christopher
authors.initials: C
authors.lastname: Piorkowski
authors.forename: Andreas
authors.initials: A
authors.lastname: Bollmann
authors.forename: Ulrike
authors.initials: U
authors.lastname: Wetzel
authors.forename: Phillip
authors.initials: P
authors.lastname: Sommer
authors.forename: Thomas
authors.initials: T
authors.lastname: Gaspar
authors.forename: Hans
authors.initials: H
authors.lastname: Kottkamp
authors.forename: Arash
authors.initials: A
authors.lastname: Arya
mesh_terms: D000368:Aged; D001282:Atrial Flutter / Q000601:surgery*; D018780:Body Surface Potential Mapping / Q000295:instrumentation / Q000379:methods; D006328:Cardiac Catheterization / Q000295:instrumentation / Q000379:methods; D016022:Case-Control Studies; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods; D016009:Chi-Square Distribution; D004867:Equipment Design; D005260:Female; D006329:Heart Conduction System / Q000601:surgery; D006801:Humans; D008280:Magnetics / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric; D016896:Treatment Outcome; D014261:Tricuspid Valve / Q000601:surgery*