title: Incidence and significance of pleomorphism in patients with postmyocardial infarction ventricular tachycardia. Acute and long-term outcome of radiofrequency catheter ablation.
abstract: OBJECTIVE
  The prognostic significance of multiple ventricular tachycardia (VT) morphologies, whether spontaneous or induced, was investigated in patients who underwent radiofrequency catheter ablation (RFCA) for postinfarction ventricular tachycardia.
  
  
  RESULTS
  We studied 137 patients with postinfarction ventricular tachycardia. Catheter ablation of all induced ventricular tachycardias was attempted. A single ventricular tachycardia morphology was documented in 102/137 patients (MONO group); 35 patients had spontaneous pleomorphism (PLEO group). Multiple VT morphologies were induced in 58/102 (57%) MONO patients and in all PLEO patients. A higher rate of arrhythmia suppression was obtained in MONO as compared to PLEO patients (162/212 [76%] vs. 43/110 [39%]). Clinical presentation (VT pleomorphism) (OR: 0.22, CI: 0.08-0.62) and the induced VT cycle (mean PLEO/MONO: 338/385 ms, OR: 1.06) were independent predictors of acute RFCA success. Among MONO patients, the procedure was successful in 75% of the patients with a single induced ventricular tachycardia compared to 64% of those with multiple tachycardias. The acute success rate was lower in PLEO patients (23%). PLEO patients had a significantly higher 3- and 5-year arrhythmia recurrence rate than MONO patients. RFCA acute success was the only independent predictor of long-term outcome in multivariate analysis.
  
  
  CONCLUSIONS
  Spontaneous, but not induced, VT pleomorphism in patients with prior myocardial infarction adversely affects the acute and long-term success rate of RFCA.
authors.affiliation: Arrhythmia Department, Centro Cardiologico Monzino, Institute of Cardiology, University of Milan, Via Parea 4, Milan 20138, Italy. pdellabella@cardiologicomonzino.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Della Bella
authors.forename: Stefania
authors.initials: S
authors.lastname: Riva
authors.forename: Gaetano
authors.initials: G
authors.lastname: Fassini
authors.forename: Francesco
authors.initials: F
authors.lastname: Giraldi
authors.forename: Marco
authors.initials: M
authors.lastname: Berti
authors.forename: Catherine
authors.initials: C
authors.lastname: Klersy
authors.forename: Nicola
authors.initials: N
authors.lastname: Trevisi
mesh_terms: D000368:Aged; D017115:Catheter Ablation / Q000379:methods*; D018572:Disease-Free Survival; D004562:Electrocardiography; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000150:complications* / Q000473:pathology; D017180:Tachycardia, Ventricular / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome