Radiofrequency catheter ablation as primary therapy for symptomatic ventricular tachycardia.

Most applications of radiofrequency (RF) catheter ablation for treatment of ventricular tachycardia (VT) have been as a treatment of last resort. The purpose of this study was to determine the efficacy and safety of RF catheter ablation as the primary treatment for symptomatic single morphology VT. Eleven of 81 patients (14%) with inducible sustained monomorphic VT underwent RF ablation as the primary treatment. One of these 11 patients had successful RF ablation of bundle branch reentry 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 symptomatic sustained monomorphic VT, at a mean cycle length of 340 +/- 60 milliseconds (ms) (range 250 to 430 ms). Six patients had coronary artery disease (CAD), one had surgical repair for tetralogy of Fallot, one had surgical repair of a ventricular septal defect, and two had a normal cardiac substrate. The VT origin was mapped using a combination of activation mapping, mid-diastolic potentials, pace mapping, and concealed entrainment. A mean of 5 +/- 3 (range 2 to 11) RF applications were administered to the putative VT foci. Eight of 10 (80%) clinical VTs were successfully ablated. There were no serious complications. Patients with VT originating from the left ventricle were offered implantable cardioverter-defibrillator back-up; however, only one patient accepted this option. At a mean follow-up of 12 +/- 7 months, only one patient had a possible arrhythmia recurrence.