title: Identification and ablation of three types of ventricular tachycardia involving the his-purkinje system in patients with heart disease.
abstract: BACKGROUND
  Ventricular tachycardia (VT) with involvement of the His-Purkinje system (HPS) can be difficult to recognize in patients with heart disease, but it may be particularly susceptible to ablation targeting the HPS. This study defines the incidence and types of HPS involvement in VT.
  
  
  RESULTS
  Involvement of the HPS was sought during electrophysiologic study with catheter mapping in 234 consecutive patients referred for catheter ablation of recurrent VT associated with heart disease. HPS VT was observed in 20 (8.5%) patients (mean ejection fraction 29%+/- 17%); in 9 (11%) of 81 patients with nonischemic heart disease and 11 (7.1%) of 153 patients with coronary artery disease (P = NS). Three types of HPS VT were observed: 16 patients (group 1) had typical bundle branch reentry, 2 patients (group 2) had bundle branch reentry and interfascicular reentry, and 2 patients (group 3) had VT consistent with a focal origin in the distal HPS. In all three groups, the VT QRS had morphologic similarity to the sinus rhythm QRS. Ablation of HPS VT was successful in all patients in whom it was attempted but produced high-degree AV block in 6 (30%). In 12 patients (60%), other VTs due to reentry through scar also were inducible.
  
  
  CONCLUSIONS
  Involvement of the HPS in VT associated with heart disease has three distinct clinical forms, all of which are susceptible to ablation. Ablation often is not sufficient as the sole therapy due to other induced VT's and conduction abnormalities, requiring pacemaker and/or defibrillator implantation.
authors.affiliation: Cardiovascular Division, Department of Internal Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Lopera
authors.forename: William G
authors.initials: WG
authors.lastname: Stevenson
authors.forename: Kyoko
authors.initials: K
authors.lastname: Soejima
authors.forename: William H
authors.initials: WH
authors.lastname: Maisel
authors.forename: Bruce
authors.initials: B
authors.lastname: Koplan
authors.forename: John L
authors.initials: JL
authors.lastname: Sapp
authors.forename: S Dinakar
authors.initials: SD
authors.lastname: Satti
authors.forename: Laurence M
authors.initials: LM
authors.lastname: Epstein
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002036:Bundle of His / Q000503:physiopathology / Q000601:surgery*; D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation; D004562:Electrocardiography; D005260:Female; D006331:Heart Diseases / Q000150:complications / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome