title: Impact of catheter ablation of ventricular tachycardia in patients with prior myocardial infarctions.
abstract: BACKGROUND
  Catheter ablation can reduce episodes of ventricular tachycardia (VT) after myocardial infarction (MI). However, the optimal endpoint of the ablation procedure remains unclear.
  
  
  METHODS
  Fifty-one consecutive patients who received catheter ablation for VT after MI were included. The procedures targeted the isthmus of all the induced, sustained VTs. When the patients with induced VTs were hemodynamically stable, radiofrequency energy was delivered at the mid-diastolic potential recording site during VT. When the patients with VTs were hemodynamically unstable, the critical channel was identified at the delayed potential recording site, showing a good pace map, with a long stimulus-QRS interval. We delivered radiofrequency energy along the identified isthmus and across the exit of the circuit.
  
  
  RESULTS
  At the end of the procedure, all VTs became non-inducible in 30 patients (59%) and some VTs were inducible in 21 patients (41%). During a mean of 40±29 months of follow-up, no VT or ventricular fibrillation recurred in 24 patients (80%) in the non-inducible group and in 12 patients (57%) in the inducible group, respectively (P=0.03). The identification of the channel during VT mapping tended to associate with no recurrence, although the difference was not statistically significant (P=0.2). Fourteen patients (27%) died during the follow-up period, mostly due to non-cardiac causes.
  
  
  CONCLUSIONS
  The catheter ablation targeting the isthmus of prior-MIVT and non-inducibility at the end of the procedure can provide a satisfactory follow-up result.
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Fukunaga
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Goya
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Hiroshima
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Hayashi
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Ohe
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Makihara
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Nagashima
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Yoshimori
authors.initials: Y
authors.lastname: An
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Shirai
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ando
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Yokoi
authors.affiliation: Department of Cardiology, Kokura Memorial Hospital, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Iwabuchi
keywords: Catheter ablation; Delayed potential; Endpoint; Prior myocardial infarction; Ventricular tachycardia