Repolarization and Activation Mapping in Ventricular Tachycardia Ablation: the REDEMPTION Study

"All ventricular tachycardia (VT) ablation procedures will be performed under general anesthesia. An epicardial approach will be performed, if clinically needed, when a detailed endocardial mapping during VT fails to reveal the complete VT critical isthmus. In case of epicardial mapping, the pericardium will be accessed percutaneously using the method described by Sosa et al.~VT activation mapping will be performed and the critical isthmus will be defined as the diastolic pathway.~Ablation will be performed at 50 W (temperature limit of 43 °C) using an irrigated ablation catheter (TactiFlex, Abbott, MN). Ablation will be aimed at VT isthmus transection. Substrate modification will be added if the patient is still inducible or in the absence of any inducible/tolerated VT. Substrate ablation will be performed based on sinus rhythm mapping, aiming at non-inducibility of any VT. At the end of procedure, programmed ventricular stimulation will be repeated."