Numerical Simulation for Design Evaluation of Thoracic Stent Graft to Investigate the Migration Phenomena and Type 1a Endoleak of Thoracic Aneurysm

Migration and endoleak phenomena are considered to be the principal reasons for Endovascular Aneurysm Repair failure. Wide differences of opinion exist regarding the nature of these critical complications. They occur when there is non-complete and ineffective contact between the endograft ends and the wall of the blood vessel. A major goal of present work is to investigate, using the Finite Element Method, the effect of nitinol stent design on the overall effectiveness of contact and radial force. The specific-patient aneurysmal thoracic aorta are challenging. The optimized stent results show better contact stability to resist the migration. They also show a good compromise of stent design requirements (flexibility and stiffness). Moreover, the new design can also prevent the risk of folding or the collapse of stent struts by mitigating the energy of eccentric deformation caused by high angulation and oversizing.