(Fig.3 A)
In another case, which was the biforate ASD and had 6mm apart between the two holes, the defects were closed by a single occluder device. The maximal diameter of the two defects and the whole size that measured from the 3D printed ASD model was 16.09mm, 6.68mm and 21.28mm, the minimum diameter of each hole and the whole size was 10.00mm, 5.17mm and 18.47mm, respectively. During simulation operation, occlusion was simulated in vitro using the 3D biforate ASD model to inform the closure plan, including the determination of target defect and size selection of the device. After the failure attempt with a 30mm occluder, a 34mm ASO was finally selected to cover all the defects successfully with the bigger defect as the optimal target defect. (Fig3 C )
In the other three cases, the size of the ASO devices selected in simulation operation according to 3D printed ASD models were identical with that applied in actual surgical procedure obtained by checking the medical records retrospectively. Moreover, simulation operation in 3D printed ASD model all showed no device replacement and occlusion-related complications such as residual leaks or device migration immediately after the in vitro simulation. (Fig.3 )