RADIOFREQUENCY CATHETER ABLATION AS PRIMARY THERAPY FOR SYMPTOMATIC VENTRICULAR-TACHYCARDIA

Most applications of radiofrequency (RF) catheter ablation for treatme nt of ventricular tachycardia (VT) have been as a treatment of last re sort. The purpose of this study was to determine the efficacy and safe ty of RF catheter ablation as the primary treatment for symptomatic si ngle morphology VT. Eleven of 81 patients (14%) with inducible sustain ed monomorphic VT underwent RF ablation as the primary treatment. One of these 11 patients had successful RF ablation of bundle branch reent ry VT and was excluded from this series. The remaining 10 patients had a mean age of 58 +/- 19 years (range 20 to 73 years), were mostly men (7 of 10 patients), and all presented with documented evidence of sym ptomatic sustained monomorphic VT, at a mean cycle length of 340+/-60 milliseconds (ms) (range 250 to 430 ms). Six patients had coronary art ery disease (CAD), one had surgical repair for tetralogy of Fallot, on e had surgical repair of a ventricular septal defect, and two had a no rmal cardiac substrate. The VT origin was mapped using a combination o f activation mapping, mid-diastolic potentials, pace mapping, and conc ealed entrainment. A mean of 5 +/- 3 (range 2 to 11) RF applications w ere administered to the putative VT foci. Eight of 10 (80%) clinical V Ts were successfully ablated. There were no serious complications. Pat ients with VT originating from the left ventricle were offered implant able cardioverter-defibrillator back-up; however, only one patient acc epted this option. At a mean follow-up of 12 +/- 7 months, only one pa tient had a possible arrhythmia recurrence.