Safety and efficacy of three-dimensional mapping systems in idiopathic ventricular tachycardia ablation

Background: Idiopathic ventricular tachycardia (VT) accounts for approximately 10% of all patients referred for evaluation of VT. 3-D mapping system has proved very useful in ablation of complex arrhythmias e.g. atrial fibrillation and VT in structural heart disease. The aim of the current study is to evaluate safety and efficacy of new 3-D mapping system in idiopathic VT ablation and comparison of between contact (Carto™) and noncontact (EnSite Array™ Catheter) mapping systems. Materials and Methods: Study population included 62 patients with idiopathic VT. (27 female 35 male, mean age 43.5 ± 22.4 years). Six patients had previously undergone unsuccessful ablation in other centers using conventional method. Site of VT/PVCs origin was RVOT in 44 (70.9%), LVOT in 4 (6.5%) and LV cavity 14 (22.6%) patients. VT was successfully ablated in 54/62 (87.1%) patients and ablation was not successful in 8/62 (12.9%) patients. VT was successfully ablated in all (6/6) patients who had previous failed ablation with conventional methods. Four (6.4%) patients developed procedure related complications. No patient with successful ablation had recurrence at six months follow up and 6/8 patients in whom ablation failed had recurrence during follow up. There was no difference in safety and efficacy of two mapping systems (success rate was 90.9% in EnSite and 82.5% in Carto (p 0.6)). Conclusion: New 3-D mapping systems (Carto™, EnSite Array™ Catheter) are very useful in ablation of idiopathic VTs with good acute success and short-term follow up. These systems are particularly useful in patients with failed ablation by conventional methods. There is no difference the two systems with regards to acute success, recurrence and complications rate.