Numerical modeling and simulations of type B aortic dissection treated by stent-grafts with different oversizing ratios
Numerical modeling and simulations of type B aortic dissection treated by stent-grafts with different oversizing ratios
复制标题
不同尺寸比覆膜支架治疗B型主动脉夹层的数值模拟
DOI：
10.1111/aor.13750
复制
发表时间：
2020-07-28
影响因子：
2.4
通讯作者：
Fu, Weiguo
中科院分区：
文献类型：
--
作者：
Meng, Zhuangyuan;Ma, Tao;Fu, Weiguo
胸主动脉腔内修复术后逆行A型夹层一直是腔内治疗的主要缺陷。本研究探讨了支架植入后导致新病变的生物力学机制，并分析了不同超大率情况下支架植入时的径向力与回弹力的关系。基于CT血管成像图像，建立了患者特有的主动脉夹层的三维几何模型。在CAD软件中进行支架设计，并在有限元分析软件中模拟不同超大率下支架-移植物的植入过程。在超大率分别为0%、3%、6%、9%、12%和15%的情况下，对每个支架-移植物模型进行6次植入模拟，比较不同组间的主动脉峰值应力。观察到主动脉应力峰值位于近端裸支架与腹主动脉壁交界处，超重率从0%增加到15%，峰值应力增加了62.2%。结论：在真实的主动脉模型中，长期较高的应力可能会导致这些区域出现新的病变，而径向力在形成新的入口中起着关键作用。
Retrograde type A dissection after thoracic endovascular aortic repair has been a major drawback of endovascular treatment. This study investigated the biomechanical mechanism of stent-graft-induced new lesions after implantation and analyzed the relationship between radial force and spring-back force of the stent-graft when it was implanted virtually under different oversizing ratios. Based on the computed tomography angiography images, a three-dimensional geometric model of a patient-specific aortic dissection was established. The stent was designed in CAD software and the stent-graft implantation procedure under different oversizing ratios was simulated in the finite element analysis software. Implantation simulations were performed six times for each stent-graft model under 0%, 3%, 6%, 9%, 12%, and 15% oversizing ratios and the peak stress of the aorta was compared among groups. It was observed that the peak stress of the aorta was located where the proximal bare stent interacted with aortic wall and its value was increased by 62.2% from 0% to 15% oversizing ratio. The conclusions are reached that the long-term higher stress in the aortic wall may lead to the emergence of new lesions in these areas, and the radial force plays a key role in the formation of a new entry in the real aorta model.