title: Epicardial mapping of sustained ventricular tachycardia in nonischemic heart disease.
abstract: BACKGROUND
  The complexity of reentrant circuits related to ventricular tachycardias decreases the success rate of radiofrequency ablation procedures.
  
  
  OBJECTIVE
  To evaluate whether the epicardial mapping with multiple electrodes carried out simultaneously with the endocardial mapping helps in ablation procedures of sustained ventricular tachycardia (VT) in patients with nonischemic heart disease.
  
  
  METHODS
  Twenty-six patients with recurrent sustained VT, of which 22 (84.6%) presenting chronic chagasic cardiomyopathy, 2 (7.7%) with idiopathic dilated cardiomyopathy and 2 with right ventricular arrhythmogenic dysplasia (RVAD), were submitted to epicardial mapping with two or three microcatheters, with 8 electrodes each, simultaneously to the conventional endocardial mapping. A catheter with a 4-mm tip was used for the ablation by radiofrequency (RF) carried out during the induced VT.
  
  
  RESULTS
  Of the 33 induced VT, 25 were mapped and 20 had their origin defined. Eleven had epicardial and 9 had endocardial origin. The programmed ventricular stimulation did not induce sustained VT in 11 (42.0%) of the 26 patients after the ablation. Events such as VT recurrence and death occurred in 10.0% of the patients submitted to successful ablation and in 59.0% of the unsuccessful cases, during a mean ambulatory follow-up of 357 ± 208 days.
  
  
  CONCLUSIONS
  Subepicardial circuits are frequent in patients with nonischemic heart disease. The epicardial mapping with multiple catheters carried out simultaneously with the endocardial mapping contributes to the identification of these circuits in a same procedure.
authors.affiliation: Escola Paulista de Medicina, UNIFESP, Rua Alves Guimarães 960/12, Pinheiros, São Paulo-SP, Brazil. georgia_guedes@uol.com.br
authors.forename: Geórgia Guedes da
authors.initials: GG
authors.lastname: Silva
authors.forename: Henrique Horta
authors.initials: HH
authors.lastname: Veloso
authors.forename: Luiz Roberto
authors.initials: LR
authors.lastname: Leite
authors.forename: Roberto Lima
authors.initials: RL
authors.lastname: Farias
authors.forename: Angelo Amato Vincenzo de
authors.initials: AA
authors.lastname: Paola
mesh_terms: D000328:Adult; D000368:Aged; D009202:Cardiomyopathies / Q000503:physiopathology*; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods; D004699:Endocardium / Q000473:pathology*; D056149:Epicardial Mapping / Q000379:methods*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000503:physiopathology* / Q000601:surgery