Effect of the degree of LAD stenosis on "competitive flow" and flow field characteristics in LIMA-to-LAD bypass surgery
Effect of the degree of LAD stenosis on "competitive flow" and flow field characteristics in LIMA-to-LAD bypass surgery
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DOI：
10.1007/s11517-012-0927-3
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发表时间：
2012-08-01
影响因子：
3.2
通讯作者：
Segers, Patrick
中科院分区：
文献类型：
--
作者：
Swillens, Abigail;De Witte, Marloes;Segers, Patrick
在左前降支（LAD）狭窄的冠状动脉搭桥术中，左乳内动脉（LIMA）的长期通畅被认为与LAD和LIMA之间的竞争性血流的程度有关。为了研究LAD狭窄严重程度对这种现象以及对LIMA和吻合区域的血液动力学的影响，基于来自实验猪研究的3D几何（从铸件获得）和血液动力学数据开发了数值LIMA-LAD模型。近端LAD压力用作上游边界条件。该模型计算了13个出口（12个间隔动脉和远端LAD），其中流速施加在收缩期，而心肌传导性施加在心室通过隐式计划。构建100（完全闭塞）、90、75和0%面积缩小的LAD狭窄。轻度LAD狭窄与LIMA中的高度竞争性流动和低壁面切应力（WSS）相关，这是一种不利的血流动力学状态，可能导致LIMA的WSS相关重塑和次优的长期LIMA旁路性能。
The long-term patency of the left internal mammary artery (LIMA) in left anterior descending (LAD) coronary stenosis bypass surgery is believed to be related to the degree of competitive flow between the LAD and LIMA. To investigate the effect of the LAD stenosis severity on this phenomenon and on haemodynamics in the LIMA and anastomosis region, a numerical LIMA-LAD model was developed based on 3D geometric (obtained from a cast) and hemodynamic data from an experimental pig study. Proximal LAD pressure was used as upstream boundary condition. The model counted 13 outlets (12 septal arteries and the distal LAD) where flow velocities were imposed in systole, while myocardial conductance was imposed in diastole via an implicit scheme. LAD stenoses of 100 (total occlusion), 90, 75 and 0 % area reduction were constructed. Low degree of LAD stenosis was associated with highly competitive flow and low wall shear stress (WSS) in the LIMA, an unfavourable hemodynamic regime which might contribute to WSS-related remodelling of the LIMA and suboptimal long-term LIMA bypass performance.