Preoperative computed tomography scan analysis of interleaflets triangles to guide aortic root repair procedures

BACKGROUND: Stabilization of the ventriculo-aortic junction (VAJ) is gaining increasing interest in the context of aortic valve repair, since its dilation is a well-recognized risk factor for long-term repair failure. Interleaflets triangles are key elements of the VAJ, but cannot be completely visualized using echocardiography. A three-dimensional (3D) reconstruction of electrocardiogram-triggered computed tomography (CT) scan images allows an analysis of the real dimensions and anatomic characteristics of the subcommissural triangles. METHODS: A method was developed to visualize the interleaflets triangle at the CT-scan based on multiplanar post-processing reconstructions. Attention was focused on the triangles' apical angle evaluation. The data obtained with CT-scan reconstructions were compared with those collected in a previous post-mortem study to validate this measurement method. RESULTS: In the CT-scan group the angles between the left and right coronary sinuses, and the right non-coronary and left non-coronary sinuses were 46.23 ± 7.79°, 47.38 ± 6.97°, 45° [range: 42.75- 50.75°], respectively, and in the post-mortem group were 45.44 ± 12.39°, 48.31 ± 1218°, 50.25 ± 7.29°. No statistically significant differences between the two groups were identified (p = 0.84, 0.81, and 0.23). CONCLUSIONS: Based on experience acquired in the operating room, the acute-angle subcommissural triangles were considered normal, the equilateral triangles mildly dilated, and the obtuse triangles severely dilated. According to this classification, different reparative approaches were selected. A CTscan 3D reconstruction method, as validated by the present data, allows a preoperative evaluation of the triangles and VAJ in order to best plan a surgical reparative approach tailored to a single patient.