title: Short-term results of substrate mapping and radiofrequency ablation of ischemic ventricular tachycardia using a saline-irrigated catheter.
abstract: OBJECTIVE
  We evaluated the safety and acute procedural efficacy of a combined electrophysiologic and anatomic approach to ablation of all inducible ventricular tachycardias (VT) during sinus rhythm using an irrigated radiofrequency (RF) ablation catheter.
  
  
  BACKGROUND
  Ventricular tachycardia associated with chronic myocardial infarction (MI) is frequently hemodynamically intolerable and associated with multiple electrocardiographic morphologies. Because traditional mapping techniques are contingent on hemodynamic stability for adequate VT mapping, VT ablation therapy for many patients has been disappointing.
  
  
  METHODS
  High-density electroanatomic mapping was performed during either sinus rhythm in 11 consecutive patients with a history of MI and ventricular arrhythmias. The RF ablation was performed using an irrigated-tip ablation catheter. All inducible VTs were targeted for catheter ablation during sinus rhythm.
  
  
  RESULTS
  The RF ablation lesions were placed in a linear fashion traversing the border zones of infarcted and normal tissue (mean of 3.4 linear lesions/patient). With this strategy, the target VT was eliminated in 9 of 11 patients (82%). Furthermore, when targeting all inducible monomorphic VTs, complete procedural success was achieved in 7 of 11 patients (64%). During the follow-up period (mean 13.1 +/- 1.9 weeks), spontaneous VT was only noted in the two patients with no acute procedural benefit.
  
  
  CONCLUSIONS
  By identifying potentially arrhythmogenic tissue during sinus rhythm, substrate mapping can guide the ablation of a majority of inducible VTs using an irrigated RF ablation catheter. This emerging therapeutic paradigm may be considered in the management of patients with multiple hemodynamically unstable monomorphic VTs.
authors.affiliation: Cardiac Arrhythmia Service, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA. vreddy@partners.org
authors.forename: Vivek Y
authors.initials: VY
authors.lastname: Reddy
authors.forename: Petr
authors.initials: P
authors.lastname: Neuzil
authors.forename: Milos
authors.initials: M
authors.lastname: Taborsky
authors.forename: Jeremy N
authors.initials: JN
authors.lastname: Ruskin
mesh_terms: D000368:Aged; D017115:Catheter Ablation / Q000009:adverse effects* / Q000379:methods*; D004562:Electrocardiography / Q000009:adverse effects / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications / Q000503:physiopathology* / Q000601:surgery*; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications; D012720:Severity of Illness Index; D012965:Sodium Chloride / Q000008:administration & dosage / Q000627:therapeutic use*; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000503:physiopathology* / Q000601:surgery*; D007507:Therapeutic Irrigation / Q000009:adverse effects* / Q000379:methods*; D013997:Time Factors
chemical_list: D012965:Sodium Chloride