Catheter ablation of idiopathic left ventricular tachycardia with multiplebreakthrough sites guided by an electroanatomical mapping system

Idiopathic ventricular tachycardia (VT) has been considered to be amenable to radiofrequency catheter ablation guided by Purkinje potentials. However, there appear to be various types of reentrant circuits associated with thi s VT deduced from the results of the successful radiofrequency catheter abl ation cases. We describe in this report a patient with idiopathic left vent ricular tachycardia which was electrically inducible and verapamil sensitiv e. Multiple earliest ventricular activation sites during tachycardia were d etected with electroanatomical mapping using the CARTO system. Multiple app lications at these sites failed to eliminate the VT. The earliest Purkinje potential was recorded at least 1.5 cm away from the earliest ventricular a ctivation sites, and the radiofrequency current application at this site re sulted in the complete abolition of this VT. The reentrant circuit of this tachycardia seemed to have multiple breakthrough sites to the ventricular m yocardium, which were distant from the requisite part of the reentrant circ uit of this VT involving the Purkinje fiber network conduction system.