Patient-specific simulation of stent-graft deployment in type B aortic dissection: model development and validation

• Main Authors: Dong, Z. (Author), Kan, X. (Author), Lin, J. (Author), Ma, T. (Author), Wang, L. (Author), Xu, X.Y (Author)
• Format: Article
• Language: English
• Published: Springer Science and Business Media Deutschland GmbH 2021
• Subjects: adult; Adult; alloy; Alloys; Anatomical information; Aneurysm, Dissecting; Angiographic images; aorta; Aorta; aortic dissection; aortic tissue; aortic wall; Article; biological model; biomechanics; Biomechanics; Blood; blood pressure; Blood pressure; Blood Vessel Prosthesis Implantation; blood vessel transplantation; Blood vessels; case report; clinical article; Computational simulation; computed tomographic angiography; Computed Tomography Angiography; computer simulation; Computer Simulation; Computerized tomography; Deployment simulation; diagnostic imaging; dissecting aneurysm; elasticity; Elasticity; Endovascular Procedures; endovascular surgery; equipment design; female; Female; finite element analysis; Finite element analysis; follow up; human; Humans; Hyperelastic materials; materials testing; Maximum principal stress; mechanical stress; Models, Cardiovascular; nitinol; pathology; polyethylene terephthalate; Presurgical planning; reproducibility; Reproducibility of Results; simulation; stent; Stents; Stress, Mechanical; tensile strength measurement; Tensile testing; TEVAR; type b aortic dissection; Type B aortic dissection; Uniaxial tensile testing; Virtual stent-graft deployment; x-ray computed tomography
• Online Access: View Fulltext in Publisher

 Thoracic endovascular aortic repair (TEVAR) has been accepted as the mainstream treatment for type B aortic dissection, but post-TEVAR biomechanical-related complications are still a major drawback. Unfortunately, the stent-graft (SG) configuration after implantation and biomechanical interactions between the SG and local aorta are usually unknown prior to a TEVAR procedure. The ability to obtain such information via personalised computational simulation would greatly assist clinicians in pre-surgical planning. In this study, a virtual SG deployment simulation framework was developed for the treatment for a complicated aortic dissection case. It incorporates patient-specific anatomical information based on pre-TEVAR CT angiographic images, details of the SG design and the mechanical properties of the stent wire, graft and dissected aorta. Hyperelastic material parameters for the aortic wall were determined based on uniaxial tensile testing performed on aortic tissue samples taken from type B aortic dissection patients. Pre-stress conditions of the aortic wall and the action of blood pressure were also accounted for. The simulated post-TEVAR configuration was compared with follow-up CT scans, demonstrating good agreement with mean deviations of 5.8% in local open area and 4.6 mm in stent strut position. Deployment of the SG increased the maximum principal stress by 24.30 kPa in the narrowed true lumen but reduced the stress by 31.38 kPa in the entry tear region where there was an aneurysmal expansion. Comparisons of simulation results with different levels of model complexity suggested that pre-stress of the aortic wall and blood pressure inside the SG should be included in order to accurately predict the deformation of the deployed SG. © 2021, The Author(s).