Abstract
Background: The two-dimensional-based LAAO size prediction system using transesophageal echocardiography is limited by the complex structure of the left atrial appendage (LAA). The LAA anatomy can be evaluated more precisely using three-dimensional images from cardiac CT; however, a CT-based sizing method has not been established. We aimed to assess the accuracy of measurements derived from cardiac computed tomography (CT) images for selecting left atrial appendage occlusion (LAAO) devices.Methods: We retrospectively reviewed 62 patients with Amplatzer Cardiac Plug and Amulet LAAO devices who underwent implantation from 2017 to 2020. The minimal, maximal, average, area-derived, and perimeter-derived diameters of the LAA landing zone were measured using CT-based images. Predicted device sizes using sizing charts were compared with actual successfully implanted device sizes.Results: The mean size of implanted devices was 27.1 ± 3.7 mm. The perimeter-derived diameter predicted device size most accurately (mean error = -0.8 ± 2.4 mm). All other parameters showed significantly larger error (mean error; minimal diameter = -4.9 ± 3.3 mm, maximal diameter = 1.0 ± 2.9 mm, average diameter = -1.6 ± 2.6 mm, area-derived diameter = -2.0 ± 2.6 mm) than the perimeter-derived diameter (all p for difference <0.05). The error for other parameters were larger in cases with more eccentrically-shaped landing zones, while the perimeter-derived diameter had minor error regardless of eccentricity. When oversizing was used, all parameters showed significant disagreement.Conclusions: The perimeter-derived diameter on cardiac CT images provided the most accurate estimation of LAAO device size regardless of landing zone eccentricity. Oversizing was unnecessary when using cardiac CT to predict an accurate LAAO size.
Utility of Cardiac CT to Assess Left Atrial Appendage Occlusion Following Device Implantation: A Comparison with Transoesophageal Echocardiography