Real-world spatial distribution of peri-device leaks on cardiac CT after WATCHMAN implantation

Abstract Background The WATCHMAN device requires post-implant imaging to assess peri-device leak (PDL) and device-related thrombus, typically with transesophageal echocardiography (TEE). Cardiac CT has emerged as a non-invasive alternative, offering high-resolution views of left atrial appendage (LAA) anatomy. However, real-world data on CT-based leak localization are limited, and standardized methods to describe leak distribution are lacking. Purpose To evaluate the spatial distribution of PDLs using gated cardiac CT at first follow-up post-WATCHMAN implantation and to apply a reproducible clock-face framework for anatomical mapping. Methods Patients undergoing WATCHMAN FLX or FLX Pro implantation were enrolled in a prospective multicenter registry and followed per local standard of care. Gated cardiac CT was performed first follow up (45-90 days) and interpreted by a central imaging core laboratory. PDLs were defined as contrast opacification within the LAA and categorized by minimum width: