Abstract 13816: Surgery for Non-Ischemic Ventricular Tachycardia: Role of Intraoperative Electro-Anatomical Mapping
Objective: Radiofrequency catheter ablation of non-ischemic VT frequently fails because of a possible non-transmural ablation due to an epicardial or intramural activation focus or hypertrophic myocardium. A retrospective study was conducted to examine the role of surgery in non-ischemic VT.
Methods: During the period from 2002 to 2011, surgeries for non-ischemic VT were performed in 17 patients. There were 15 male and 2 female patients. The average age was 59±14 years. The underlying substrates were cardiomyopathy in 11 patients, an idiopathic LV aneurysm in 2, an LV lipoma in 2, idiopathic in 1, and ARVC in 1. The indication for the surgery was medically refractory or incessant VT in all, including in 10 patients with VT storms (≥3 episodes per day). Ten patients had an ICD or CRTD implanted preoperatively and 10 had undergone a failed endocardial and/or epicardial radiofrequency catheter ablation. All the patients underwent a map-guided procedure for VT. An electro-anatomical mapping system was used in 13 patients intraoperatively. In the patients with hypertrophic cardiomyopathy, the thickness of the LV at the origin of the VT determined by echocardiography was 14.3±1.9 mm, and therefore the VT origin was cryoablated both from the endocardium and epicardium to create a transmural cryolesion. The lipoma was resected and the border was circumferentially cryoablated. An electrophysiological study was repeated in all patients postoperatively.
Results: There were no operative or late deaths. The electro-anatomical mapping precisely located the origin of the VT with a three dimensional cardiac feature as an anatomical reference. The postoperative electrophysiological study revealed freedom from clinical VT in all patients. One patient with inducible non-clinical VT received an ICD. None of the patients had any recurrence of VT and all the patients with both preoperatively and postoperatively implanted ICDs have been free from any ICD shocks during a follow-up period of 42±33 months.
Conclusions: The surgery provides an excellent suppression of VT in the patients with non-ischemic VT and should be indicated in the patients with refractory VT. The intraoperative electro-anatomical mapping is crucial for the precise localization of the VT origin.
- © 2011 by American Heart Association, Inc.