Background: Intramural site of origin is a major cause of ablation failure of ventricular arrhythmias and the optimal strategy is unclear. This study investigated the efficacy of a stepwise ablation approach for intramural outflow tract (OT) premature ventricular complexes (PVCs) guided by mapping of the septal coronary venous system. Methods: Consecutive patients with OT PVCs were included in which an intramural origin was confirmed by demonstration of earliest activation in a septal coronary vein. Radiofrequency ablation was performed from the closest endocardial site in the left (LVOT) and/or right ventricular OT (RVOT) independent of the local activation time. If there was no suppression by endocardial ablation, retrograde transvenous ethanol infusion with a single or double balloon technique was performed, targeting the earliest septal coronary vein. If venous anatomy was not suitable for ethanol ablation or if this failed, bipolar ablation was performed. Results: Sixty patients (

Background: The PRAETORIAN trial investigated the efficacy and safety of the subcutaneous implantable cardioverter-defibrillator (S-ICD) compared with transvenous ICD (TV-ICD) and showed non-inferiority of the S-ICD with regard to the composite endpoint of device-related complications and inappropriate shocks (IAS) after 49.1 months. Complications associated with transvenous leads are expected to occur after longer follow-up. The PRAETORIAN-XL trial aims to investigate whether the S-ICD is superior to the TV-ICD with respect to device-related complications at 8-year follow-up. Methods: The PRAETORIAN trial randomized patients with a class I or IIa indication for ICD therapy without the need for pacing to either S-ICD or TV-ICD among 39 centers in the US and Europe between March 2011 and January 2017. The follow-up was extended after 49.1 months with an additional four years, for the PRAETORIAN-XL trial. The primary endpoint was the composite of all device-related complications. Complic