Assessment of Device Neoendothelialization With Cardiac Computed Tomography Angiography After Transcatheter Closure of Atrial Septal Defect

Background: Although the transcatheter closure of atrial septal defect was established as the treatment of choice several decades ago, the process of device neoendothelialization (NE) in humans is not well understood. We aimed to measure the extent of device NE using cardiac computed tomography angiography and analyze its risk factors. Methods: Between January 2005 and February 2021, we retrospectively reviewed 164 devices of 112 patients on cardiac computed tomography angiography. We investigated device shape, contrast opacification within the device that differentiated device NE, and device-related thrombosis or vegetation. Risk factor analysis for major adverse cardiovascular events and incomplete NE according to the postprocedural period was performed. Results: Seventy patients (62.5%) were women, with a median (range) age at the time of device closure of 44.5 (0.6-79.2) years. The mean (±SD) defect size was 16.6 (±7.8) mm, and patients were followed for 35.9±33.9 months. After 6 months of device implantation, 35% of the devices (42/120) had incomplete NE. The intensity of intradevice opacification shifted from complete to partial or nonopacification over time (P<0.001), and a similar pattern was observed in the shunt flow (P<0.001). The bulkiness of devices also decreased in proportion to the postprocedural period (P<0.001). Risk analysis revealed device diameter (hazard ratio, 1.18 [95% CI, 1.04-1.27]; P<0.001) as the only significant factor of incomplete NE and major adverse events. Conclusions: Incomplete NE of atrial septal defect devices was identified on cardiac computed tomography angiography in significant numbers after 6 months of the procedure. The device diameter was related to incomplete NE and major adverse events. Further prospective and multicenter studies are warranted to validate this new assessment of device NE.