title: Simplified electrophysiologically directed catheter ablation of recurrent common atrial flutter.
abstract: BACKGROUND
  Despite verification of bidirectional conduction block after radiofrequency (RF) catheter ablation in the inferior vena cava (IVC)-tricuspid annulus (TA) isthmus, recurrence of common atrial flutter is relatively common. Although complete linear reablation is usually performed, we evaluated a simplified electrophysiological strategy selectively targeting recovered conducting isthmus tissue.
  
  
  RESULTS
  Twenty-one patients (18 men and 3 women, age, 54+/-10 years) with a recurrence of typical atrial flutter 6+/-7 months after an apparently successful catheter ablation in the IVC-TA isthmus prospectively underwent electrophysiologically targeted reablation during flutter. Sites with narrow electrograms or fractionated electrograms interposed between adjacent sites with double potentials considered to represent gaps were ablated without movement of the catheter. Mapping showed that 18 of 21 patients had a single gap. Successful ablation required a single application in 14 patients and, in the group as a whole, a median of one application (mean, 2+/-2; range, 1 to 11) with resultant bidirectional block in 13 of 16. A single narrow electrogram (duration, 48+/-6 ms; amplitude, 0.1+/-0.05 mV) was noted at the successful site in 11, whereas a fractionated electrogram (97+/-32 ms, 0.05+/-0.04 mV, P<.05) was noted in 9. There were four additional recurrences during a follow-up at 7+/-5 months; three were similarly ablated with a median of one pulse.
  
  
  CONCLUSIONS
  Transmural ablation lesions in the isthmus can be recognized during flutter by double potentials separated by an isoelectric interval. Postablation recurrent flutter is usually due to a single discrete recovered gap; this is represented by a single or a fractionated potential spanning the isoelectric interval of adjacent double potentials, which can be selectively targeted to minimize repeat ablation.
authors.affiliation: Service de Rhythmologie, Hôpital Cardiologique du Haut-Lévêque, Bordeaux-Pessac, France.
authors.forename: D C
authors.initials: DC
authors.lastname: Shah
authors.forename: M
authors.initials: M
authors.lastname: Haïssaguerre
authors.forename: P
authors.initials: P
authors.lastname: Jaïs
authors.forename: B
authors.initials: B
authors.lastname: Fischer
authors.forename: A
authors.initials: A
authors.lastname: Takahashi
authors.forename: M
authors.initials: M
authors.lastname: Hocini
authors.forename: J
authors.initials: J
authors.lastname: Clementy
mesh_terms: D000328:Adult; D001282:Atrial Flutter / Q000628:therapy*; D017115:Catheter Ablation / Q000379:methods*; D015331:Cohort Studies; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D000078702:Radiofrequency Therapy; D014261:Tricuspid Valve / Q000528:radiation effects; D014682:Vena Cava, Inferior / Q000528:radiation effects