Double ventricular tachycardias associated with an anatomical isthmus identified by a computed tomography-derived channel.

We describe a 47-year-old woman with ischemic ventricular tachycardia (VT) with repetitive implantable cardioverter-defibrillator shocks, requiring ablation. Preprocedural computed tomography (CT) demonstrated a single anatomical channel on the inferior-basal infarcted area between less than a 3-mm wall-thinning area and the mitral annulus, which suggested the circuit of two VTs observed. In addition, distribution of less than 2 mm and less than 3 mm wall-thinning area can explain the mechanism of the variation of the QRS morphology and S-QRS interval during entrainment. Ablation in this region resulted in no VT inducibility and the absence of any VTs for 2 years. CT wall thinning data may allow us to understand the mechanism and circuit of VT and aid VT ablation procedures.