A Case of Radiofrequency Catheter Ablation of Ventricular Tachycardia Associated with an Old Myocardial Infarction Guided by a Noncontact Mapping System

We describe here a 72-year-old man with ventricular tachycardia (VT) associated with an old myocardial infarction, in whom noncontact mapping guided radiofrequency catheter ablation (RFCA) successfully eliminated the VT. Right ventricular pacing induced 3 VTs with different QRS morphologies and axes, 2 of which were hemodynamically unstable. A dynamic virtual activation map constructed during the VTs superimposed on a virtual voltage map constructed during sinus rhythm demonstrated that all VTs shared a single large myocardial scar in the inferolateral portion of the left ventricle which served as a slow conduction zone. All VTs were eliminated by RFCA at the exit or within the critical slow conduction zone. The patient has been free from any VT recurrences during a follow-up period of 22 months.