title: Outcome of ventricular tachycardia ablation in patients with nonischemic cardiomyopathy: the impact of noninducibility.
abstract: BACKGROUND
  Ablation failure and recurrence rates after ventricular tachycardia (VT) ablation in nonischemic cardiomyopathy are high and the optimal procedural end point is not well defined. This study assessed the outcome after ablation, the impact of noninducibility, and other potential predictors of VT recurrence.
  
  
  RESULTS
  Forty-five patients with nonischemic cardiomyopathy (60±16 years; left ventricular ejection fraction, 44±14%) accepted for VT ablation were included. Epicardial mapping was performed in 29 (64%). A median of 2 (first-to-third quartile, 2-4) VTs (cycle length, 342±77 ms) were induced per patient. After ablation, the complete programmed electric stimulation protocol (3 drive cycle length, 3 extrastimuli ≥200 ms, and burst≥2 sites) was repeated. Complete success (noninducibility of any monomorphic VT) was achieved in 17 patients (38%), partial success (elimination of clinical VT, persistent inducibility of nonclinical VT) in 17 patients (38%), and failure (persistent inducibility of clinical VT) in 11 patients (24%). During 25±15 months of follow-up, VT occurred in 24 patients (53%), but the 6-month VT burden was reduced by ≥75% in 79%. Recurrence rates were low after complete procedural success (18%), but high after both partial success (77%) and failure (73%). Non-complete procedural success was the strongest predictor of VT recurrence (hazard ratio, 8.20; 95% confidence interval, 2.37-28.43; P=0.001).
  
  
  CONCLUSIONS
  Although 53% of patients had VT during follow-up, the 6-month VT burden was decreased by ≥75% in 79%. Recurrence rates are low after complete procedural success, but high after both partial success and failure. Non-complete procedural success was the strongest predictor of VT recurrence.
authors.affiliation: Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Sebastiaan R D
authors.initials: SR
authors.lastname: Piers
authors.forename: Darryl P
authors.initials: DP
authors.lastname: Leong
authors.forename: Carine F B
authors.initials: CF
authors.lastname: van Huls van Taxis
authors.forename: Mohammad
authors.initials: M
authors.lastname: Tayyebi
authors.forename: Serge A
authors.initials: SA
authors.lastname: Trines
authors.forename: Daniël A
authors.initials: DA
authors.lastname: Pijnappels
authors.forename: Victoria
authors.initials: V
authors.lastname: Delgado
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Schalij
authors.forename: Katja
authors.initials: K
authors.lastname: Zeppenfeld
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D018780:Body Surface Potential Mapping / Q000379:methods; D009202:Cardiomyopathies / Q000150:complications* / Q000175:diagnosis / Q000401:mortality; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012008:Recurrence; D012189:Retrospective Studies; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D017180:Tachycardia, Ventricular / Q000150:complications* / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome
keywords: catheter ablation; nonischemic cardiomyopathy; ventricular tachycardia