Magnitude and direction of pulsatile displacement forces acting on thoracic aortic endografts.

摘要: Purpose: To assess 3-dimensional (3D) pulsatile displacement forces (DF) acting on thoracic endografts using 3D computational techniques. Methods: A novel method to quantitate the flow and pressure fields aortic wall dynamics in patient-specific anatomical models based cardiac-gated computed tomography (CT) scans was used construct simulations of proximal mid-descending aorta. Endografts varying lengths diameters were implanted these models. The magnitude direction DF vector calculated expressed Newtons (N). This included effects both shearing stresses blood. Results: increased with increasing diameter length. 36-mm endograft aorta had a mean 21.7 N peak systolic 27.8 an end-diastolic 16.7 N. Conversely, 30-mm descending 14.9 N, DFs 18.9 11.5, respectively. orientation varied depending angulation tortuosity; general, perpendicular greater curvature rather than along downstream longitudinal centerline axis as is commonly believed. pointed primarily cranial for sideways simulation. Furthermore, it shown that elevated plays important role DF; increase blood resulted approximately linearly proportional DF. Conclusion: varies location endograft, but all instances, caudal axial imaging. counter intuitive notion act downward flow. Therefore, we postulate migration may be different from abdominal since involve upward movement graft. Computational methods can enhance understanding loads experienced vivo by therefore improve their design performance.