Use of a closed loop irrigated catheter in epicardial ablation of ventricular tachycardia.

PURPOSE: Catheter ablation of ventricular tachycardia (VT) often requires a combined epicardial and endocardial approach. An open irrigated catheter for epicardial ablation of ventricular tachycardia is commonly used. However, this can be associated with problems of fluid accumulation in the pericardial space necessitating repeated aspirations and interfering with catheter-tissue contact. A closed loop irrigated catheter can be a viable alternative to overcome these problems. We report our first three cases of epicardial VT ablation using a closed loop irrigated ablation catheter (Chilli II, Boston Scientific).
METHODS: Catheter ablation of ventricular tachycardia was performed via epicardial and endocardial approaches using a closed loop irrigated ablation catheter (Chilli II, Boston Scientific) and using 3-D mapping with EnSite/NavX system. Patients were routinely followed up after the catheter ablation procedure in clinic for any recurrence of ventricular arrhythmia.
RESULTS: We report our first three cases of epicardial VT ablation using a closed loop irrigated ablation catheter. Power delivery was adequate with mean power of 15.2 ± 2.8, 31.1 ± 3.8, and 25.0 ±  3.3 W, respectively, in the three patients. No impedance rises were noted during the lesion formation. There was no recurrence of VT in any of the patients after 3 months of follow-up.
CONCLUSIONS: To our knowledge, we report the first case series of epicardial VT ablation using a closed loop irrigated catheter and the EnSite/NavX mapping system. The advantages of closed irrigation, especially in conjunction with impedance-based anatomical mapping, warrant further study of its efficacy in catheter ablation from the pericardial space.