【作者】 李颖；

【导师】 刘有军；

【作者基本信息】 北京工业大学 ， 生物医学工程（专业学位）， 2018， 硕士

【摘要】 冠脉支架植入作为治疗冠状动脉分叉病变的重要方法已经在临床上得到广泛的应用。但是在实际临床操作中,由于情况的复杂,会在一定程度上出现术后分支血管变形、血流变化等问题,进而对分支血管血液灌注以及介入治疗效果造成一定的影响。本文利用有限元分析的方法,探究冠脉支架植入分叉血管对分支血管影响,以期为临床医生提供相关理论参考。本文主要研究内容如下:1、冠脉支架植入不同斑块条件的冠脉狭窄分叉血管对其分支血管的影响。建立冠脉支架模型以及不同斑块条件的冠脉狭窄分叉血管理想模型。在此基础上,模拟冠脉支架从其未装配状态到植入冠脉狭窄分叉血管服役的过程。分析冠脉支架的植入对分支血管应力以及形态的影响。此外,进行冠脉支架植入冠脉狭窄分叉血管后分支血管血流分析,探究冠脉支架植入冠脉狭窄分叉血管对其分支血管内血流的影响。2、冠脉支架植入个性化冠脉狭窄分叉血管模型的构建。利用患者冠脉CT图像构建血管、斑块相互独立的冠脉狭窄分叉血管个性化模型,并实现冠脉支架与之匹配。研究结果显示:冠脉支架植入冠脉狭窄分叉血管过程中,首先,在冠脉支架扩张到最大位置时分支血管应力及形态变化最明显。其次,随着斑块狭窄程度的增加,分支血管应力及形态变化越明显;随着斑块长度的增加亦或是斑块距分叉口距离的增加,分支血管应力及形态变化有所减小。此外,相比于不同斑块长度以及不同斑块位置,不同斑块狭窄程度模型在冠脉支架植入分叉血管的过程中,其分支血管应力及形态变化均更为明显。分析冠脉支架植入冠脉狭窄分叉血管后其分支血管血流变化,可知冠脉支架植入后其分支血管靠近分叉口位置区域出现了不规则的流场分布,同时伴有分支血管血液流量的减小。冠脉支架与冠脉狭窄分叉血管个性化模型的匹配模拟过程中,冠脉支架的应力变化合理,形态变化均匀,且匹配结果与分叉血管管腔走势较为贴合。由上述研究结果得到如下结论:1、冠脉支架植入冠脉狭窄分叉血管的过程中,对分支血管自身的影响主要表现为分支血管应力的改变以及形态的变化,并且这一影响在冠脉支架扩张到最大位置时最为显著。其次,冠脉支架植入斑块狭窄程度较大、长度较短、距分叉口距离较近的分叉血管,更容易对分支血管产生较大的影响。此外,相比于斑块长度以及斑块位置,斑块的狭窄程度在冠脉支架植入分叉血管的过程中对分支血管的影响表现更为明显。因而处理上述情况病变时,临床医生应给予更多的关注。2、冠脉支架植入分叉血管对分支血管血液流动的影响,主要表现为分支血管内流场分布的变化以及分支血管血流量的减小,这也会在一定程度上影响血管下游供血。3、冠脉支架植入个性化冠脉狭窄分叉血管模型的构建,为进一步探讨冠脉支架植入对其分支血管的影响奠定基础。本研究利用有限元分析的方法探究冠脉支架植入不同斑块条件的冠脉狭窄分叉血管对分支血管的影响,为临床医生提供了一定的理论依据。同时完成冠脉支架植入个性化冠脉狭窄分叉血管模型的构建,为后续研究奠定了工作基础。更多还原

【Abstract】 Coronary stent as an important method in the treatment of coronary bifurcation lesions has been widely used in clinic.But in the actual clinical operations,because of the complexity of the situation,some problems may occur in a certain extent,such as postoperative side branch vessel distortion and blood flow change.These will also cause certain influence on blood perfusion of side branch vessel and the effect of interventional therap.The purpose of this research is that explore the influence of side branch vessel during the coronary stent insert the coronary artery bifurcation vessel by using the method of finite element analysis,in order to provide theoretical reference for clinical doctor.The research contents are as follows:1.The influence of coronary stent inserting different plaque situation coronary stenosis bifurcation vessel on side branch vessel.Coronary stent model and different plaque situation coronary stenosis bifurcation vessel ideal models are built to simulate the process from the coronary stent unassembled state to the inserting coronary stenosis bifurcation vessel service status.Then,analyzing the influence of coronary stent inserting on side branch vessel stress and morphology.In addition,blood flow analysis of side branch vessel after coronary stent inserting coronary stenosis bifurcation vessel is conducted to investigate the influence of coronary stent inserting the coronary stenosis bifurcation vessel on side branch vessel blood flow.2.Establishment coronary stent inserting personalized coronary stenosis bifurcation vessel model.The patient coronary artery CT image is used to build the coronary stenosis bifurcation vessel personalized model with independent vessel and plaque.Then,matching the model with coronary stent.The results showed that: during the process of coronary stent insert different plaque situation bifurcation vessels,first,the stress and morphological of side branch vessel changed most pronounced at the moment of the coronary stent inflated to the largest position.Second,with the increase of plaque stenosis degree,the stress and morphological of side branch vessel changed more obvious.With the increase of plaque length or the increase of distance form bifurcation to plaque,the stress change and deformation of side branch vessel decreased.In addition,compared with the different plaque length model and different plaque location model,the change of stress and morphological on side branch vessel were more obvious in different plaque stenosis degree model,during the process of coronary stent insert bifurcation vessel.In the analysis of blood flow change in branch coronary artery after the coronary stent inserting coronary stenosis bifurcation vessel,irregular flow field distribution appeared near the bifurcation site of branch vessels after the coronary stent inserting,the blood flow of side branch vessel was reduced at the same time.In the matching between coronary stent and coronary stenosis bifurcation vessel personalized model,the change was reasonable of coronary stent stress and shape,also it was nicely matched between coronary stent and bifurcation vessel lumen.Getting the following conclusion from the above results:1.During the process of coronary stent inserted coronary stenosis bifurcation vessel,the changes in stress and morphology are two main performance of the influence on the side branch vessel.And the influence is most significant at the moment of coronary stent inflated to the largest position.Then,it is more likely to have a greater influence on side branch vessel in the process of coronary stent inserting larger stenosis plaque,shorter length plaque,and closer distance plaque coronary stenosis bifurcation vessel.In addition,comparing with plaque length and plaque location,the influence on side branch vessel of plaque stenosis degree is more obvious.Therefore,clinicians should pay more attention when dealing with the above-mentioned conditions.2.During the process of coronary stent inserting the bifurcation vessel,the changes of the flow field distribution and the decrease in blood flow are two main performance of the influence on the side branch vessel.These will affect the downstream blood supply to some extent.3.Coronary stent inserting personalized coronary stenosis bifurcation vessel model to lay the foundation for futher study on the influence of stent inserting on coronary bifurcation side branch.Finite element analysis is used to explore the influence of coronary stent inserting coronary stenosis bifurcation vessel of different plaque situation on side branch vessel,it provides a certain theoretical reference for clinicians.Coronary stent inserting personalized coronary stenosis bifurcation vessel model is build to lay the foundation for the following study.更多还原