The aortic cusps are the predominant successful ablation site of idiopathic outflow-tract ventricular arrhythmias.

Abstract Background Data regarding the successful ablation site of idiopathic outflow tract (OT) ventricular arrhythmias (VAs) in the modern era of mapping and ablation are limited. Methods and results Over a 4-year period, a total of 309 patients underwent detailed activation mapping of OT VAs including the right ventricular outflow tract (RVOT), the left ventricular outflow tract (LVOT) and the aortic cusps (AC), and the coronary venous system. 244 cases were successfully ablated at the index procedure (78.9%). The successful ablation site was more frequently located at the LVOT/ACs (51.6%) followed by RVOT (36.2%). In particular, the ACs was the predominant successful ablation site of idiopathic OT VAs (46.7%). An epicardial site of origin was predictor of ablation failure (p  Conclusions The ACs is the predominant successful ablation site of idiopathic OT VAs. Take-home message The aortic cusps are the predominant successful ablation site of idiopathic idiopathic outflow tract ventricular arrhythmias.