title: Scar dechanneling: new method for scar-related left ventricular tachycardia substrate ablation.
abstract: BACKGROUND
  Ventricular tachycardia (VT) substrate ablation usually requires extensive ablation. Scar dechanneling technique may limit the extent of ablation needed.
  
  
  RESULTS
  The study included 101 consecutive patients with left ventricular scar-related VT (75 ischemic patients; left ventricular ejection fraction, 36 ± 13%). Procedural end point was the elimination of all identified conducting channels (CCs) by ablation at the CC entrance followed by abolition of residual inducible VTs. By itself, scar dechanneling rendered noninducibility in 54.5% of patients; ablation of residual inducible VT increased noninducibility to 78.2%. Patients needing only scar dechanneling had a shorter procedure (213 ± 64 versus 244 ± 71 minutes; P = 0.027), fewer radiofrequency applications (19 ± 11% versus 27 ± 18%; P = 0.01), and external cardioversion/defibrillation shocks (20% versus 65.2%; P < 0.001). At 2 years, patients needing scar dechanneling alone had better event-free survival (80% versus 62%) and lower mortality (5% versus 11%). Incomplete CC-electrogram elimination was the only independent predictor (hazard ratio, 2.54 [1.06-6.10]) for the primary end point. Higher end point-free survival rates were observed in patients noninducible after scar dechanneling (log-rank P = 0.013) and those with complete CC-electrogram elimination (log-rank P = 0.013). The complications rate was 6.9%, with no deaths.
  
  
  CONCLUSIONS
  Scar dechanneling alone results in low recurrence and mortality rates in more than half of patients despite the limited ablation extent required. Residual inducible VT ablation improves acute results, but patients who require it have worse outcomes. Recurrences are mainly related to incomplete CC-electrogram elimination.
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain. berruezo@clinic.ub.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Berruezo
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Fernández-Armenta
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Andreu
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Penela
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Csaba
authors.initials: C
authors.lastname: Herczku
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Reinder
authors.initials: R
authors.lastname: Evertz
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Cipolletta
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Acosta
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Roger
authors.initials: R
authors.lastname: Borràs
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Arbelo
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Jose María
authors.initials: JM
authors.lastname: Tolosana
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Brugada
authors.affiliation: From the Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), Barcelona, Spain.
authors.forename: Lluis
authors.initials: L
authors.lastname: Mont
mesh_terms: D000200:Action Potentials; D000368:Aged; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D002921:Cicatrix / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D018572:Disease-Free Survival; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006339:Heart Rate; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D013318:Stroke Volume; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000209:etiology / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D016277:Ventricular Function, Left; D020257:Ventricular Remodeling
keywords: catheter ablation; tachycardia, ventricular