A procedure to simulate coronary artery bypass graft surgery
A procedure to simulate coronary artery bypass graft surgery
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DOI：
10.1007/s11517-007-0201-2
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发表时间：
2007-09-01
影响因子：
3.2
通讯作者：
Holzapfel, Gerhard A.
中科院分区：
文献类型：
--
作者：
Cacho, Fernando;Doblare, Manuel;Holzapfel, Gerhard A.
在冠状动脉旁路移植术（CABG）中，受累组织被过度拉伸，这可能导致内膜增生和移植失败。我们提出了一种用于模拟传统CABG手术的计算方法，并分析了两个临床相关参数对动脉和移植物反应的影响，即，切口长度和插入角度。计算结构分析是基于人体冠状动脉和人体隐静脉的实际三维血管尺寸。分析考虑了端侧吻合的结构、残余应力以及典型的各向异性和非线性血管行为。冠状动脉被建模为三层厚壁管。采用有限元方法预测冠状动脉旁路移植术各阶段的变形和应力分布。动脉切口的微小变化对动脉开口的大小有较大的影响，而动脉开口的大小仅取决于残余应力状态。切口长度对移植物形状和移植物壁中的应力具有关键影响。在脚跟区域的应力高于那些在脚趾区域。在静脉组织和宿主动脉之间的所有过渡处，机械环境的变化沿着严重。特别是应力集中发生在切口端部。所提出的计算方法可能是有用的设计冠状动脉吻合装置，以减少手术创伤。它可以提高血管疾病的定量知识，并作为一种工具，虚拟规划血管手术。
In coronary artery bypass graft (CABG) surgery the involved tissues are overstretched, which may lead to intimal hyperplasia and graft failure. We propose a computational methodology for the simulation of traditional CABG surgery, and analyze the effect of two clinically relevant parameters on the artery and graft responses, i.e., incision length and insertion angle for a given graft diameter. The computational structural analyses are based on actual three-dimensional vessel dimensions of a human coronary artery and a human saphenous vein. The analyses consider the structure of the end-to-side anastomosis, the residual stresses and the typical anisotropic and nonlinear vessel behaviors. The coronary artery is modeled as a three-layer thick-walled tube. The finite element method is employed to predict deformation and stress distribution at various stages of CABG surgery. Small variations of the arterial incision have relatively big effects on the size of the arterial opening, which depends solely on the residual stress state. The incision length has a critical influence on the graft shape and the stress in the graft wall. Stresses at the heel region are higher than those at the toe region. The changes in the mechanical environment are severe along all transitions between the venous tissue and the host artery. Particular stress concentrations occur at the incision ends. The proposed computational methodology may be useful in designing a coronary anastomotic device for reducing surgical trauma. It may improve the quantitative knowledge of vessel diseases and serve as a tool for virtual planning of vascular surgery.