Title: Hemodynamic effects of stent-graft introducer sheath during thoracic endovascular aortic repair Show Chinese title

Title: 胸主动脉腔内修复术期间支架移植物引入鞘管的血流动力学效应

Abstract: Thoracic endovascular aortic repair (TEVAR) has become the standard treatment of a variety of aortic pathologies. The objective of this study is to evaluate the hemodynamic effects of stent-graft introducer sheath during TEVAR. Three idealized representative diseased aortas of aortic aneurysm, coarctation of the aorta, and aortic dissection were designed. Computational fluid dynamics studies were performed in the above idealized aortic geometries. An introducer sheath routinely used in the clinic was virtually-delivered into diseased aortas. Comparative analysis was carried out to evaluate the hemodynamic effects of the introducer sheath. Results show that the blood flow to the supra-aortic branches would increase above 9% due to the obstruction of the introducer sheath. The region exposed to high endothelial cell activation potential (ECAP) expands in the scenarios of coarctation of the aorta and aortic dissection, which indicates that the probability of thrombus formation may increase during TEVAR. The pressure magnitude in peak systole shows an obvious rise and a similar phenomenon is not observed in early diastole. The blood viscosity in the aortic arch and descending aorta is remarkably altered by the introducer sheath. The uneven viscosity distribution confirms the necessity of using non-Newtonian models and high viscosity region with high ECAP further promotes thrombosis. Our results highlight the hemodynamic effects of stent-graft introducer sheath during TEVAR, which may associate with perioperative complications. Show Chinese abstract

Abstract: 胸主动脉腔内修复术（TEVAR）已成为多种主动脉病变的标准治疗方法。 本研究的目的是评估在TEVAR过程中支架移植物输送鞘对血流动力学的影响。 设计了三种理想化的代表性病变动脉瘤、主动脉缩窄和主动脉夹层。 在上述理想化的主动脉几何结构中进行了计算流体动力学研究。 将临床上常规使用的输送鞘虚拟地置入病变动脉中。 进行了比较分析以评估输送鞘的血流动力学影响。 结果表明，由于输送鞘的阻塞，主动脉分支以上的血流增加了9%以上。 在主动脉缩窄和主动脉夹层的情况下，暴露于高内皮细胞激活潜力（ECAP）的区域扩大，这表明在TEVAR期间血栓形成的可能性可能增加。 收缩期峰值的压力幅度明显上升，而在早期舒张期未观察到类似现象。 主动脉弓和降主动脉中的血液粘度受到输送鞘的显著影响。 不均匀的粘度分布证实了使用非牛顿模型的必要性，高粘度区域与高ECAP进一步促进了血栓形成。 我们的结果强调了在TEVAR过程中支架移植物输送鞘的血流动力学影响，这可能与围手术期并发症有关。