title: Irrigated radiofrequency catheter ablation guided by electroanatomic mapping for recurrent ventricular tachycardia after myocardial infarction: the multicenter thermocool ventricular tachycardia ablation trial.
abstract: BACKGROUND
  Recurrent ventricular tachycardia (VT) is an important cause of mortality and morbidity late after myocardial infarction. With frequent use of implantable cardioverter-defibrillators, these VTs are often poorly defined and not tolerated for mapping, factors previously viewed as relative contraindications to ablation. This observational multicenter study assessed the outcome of VT ablation with a saline-irrigated catheter combined with an electroanatomic mapping system.
  
  
  RESULTS
  Two hundred thirty-one patients (median LV ejection fraction, 0.25; heart failure in 62%) with recurrent episodes of monomorphic VT (median, 11 in the preceding 6 months) caused by prior myocardial infarction were enrolled. All inducible monomorphic VTs with a rate approximating or slower than any spontaneous VTs were targeted for ablation guided by electroanatomic mapping during sinus rhythm and/or VT. Patients were not excluded for multiple VTs (median, 3 per patient) or unmappable VT (present in 69% of patients). Ablation abolished all inducible VTs in 49% of patients. The primary end point of freedom from recurrent incessant VT or intermittent VT after 6 months of follow-up was achieved for 123 patients (53%). In 142 patients with implantable cardioverter-defibrillators before and after ablation for intermittent VT who survived 6 months, VT episodes were reduced from a median of 11.5 to 0 (P<0.0001). The 1-year mortality rate was 18%, with 72.5% of deaths attributed to ventricular arrhythmias or heart failure. The procedure mortality rate was 3%, with no strokes.
  
  
  CONCLUSIONS
  Catheter ablation is a reasonable option to reduce episodes of recurrent VT in patients with prior myocardial infarction, even when multiple and/or unmappable VTs are present. This population remains at high risk for death, warranting surveillance and further study.
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Boston, MA 02115, USA. wstevenson@partners.org
authors.forename: William G
authors.initials: WG
authors.lastname: Stevenson
authors.forename: David J
authors.initials: DJ
authors.lastname: Wilber
authors.forename: Andrea
authors.initials: A
authors.lastname: Natale
authors.forename: Warren M
authors.initials: WM
authors.lastname: Jackman
authors.forename: Francis E
authors.initials: FE
authors.lastname: Marchlinski
authors.forename: Timothy
authors.initials: T
authors.lastname: Talbert
authors.forename: Mario D
authors.initials: MD
authors.lastname: Gonzalez
authors.forename: Seth J
authors.initials: SJ
authors.lastname: Worley
authors.forename: Emile G
authors.initials: EG
authors.lastname: Daoud
authors.forename: Chun
authors.initials: C
authors.lastname: Hwang
authors.forename: Claudio
authors.initials: C
authors.lastname: Schuger
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Bump
authors.forename: Mohammad
authors.initials: M
authors.lastname: Jazayeri
authors.forename: Gery F
authors.initials: GF
authors.lastname: Tomassoni
authors.forename: Harry A
authors.initials: HA
authors.lastname: Kopelman
authors.forename: Kyoko
authors.initials: K
authors.lastname: Soejima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakagawa
mesh_terms: D000368:Aged; D018780:Body Surface Potential Mapping / Q000295:instrumentation / Q000379:methods*; D017115:Catheter Ablation / Q000295:instrumentation / Q000379:methods* / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation / Q000379:methods*; D009203:Myocardial Infarction / Q000150:complications / Q000401:mortality / Q000601:surgery*; D015996:Survival Rate; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000401:mortality / Q000601:surgery*