Nicolás M, Peña E, Malvè M, Martínez M A
Aragón Institute of Engineering Research (I3A), University of Zaragoza, Zaragoza, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza, Spain.
Aragón Institute of Engineering Research (I3A), University of Zaragoza, Zaragoza, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza, Spain.
J Theor Biol. 2015 Dec 21;387:228-40. doi: 10.1016/j.jtbi.2015.09.028. Epub 2015 Oct 13.
An inferior vena cava filter is a medical device that is implanted in the inferior vena cava and is in charge of capturing blood clots before they reach the lungs, preventing from pulmonary embolism. There are some clinical problems regarding the use of inferior vena cava filters. One of them is the difficulty when retrieving the device due to the remodeling of the vena cava. Huge effort has been made in creating computational models that reproduce tissue remodeling, but no attention has been paid to the fibrosis phenomenon occurring in the inferior vena cava. In this work, a continuum computational model that reproduces the fibrosis in the presence of an antithrombotic filter is presented. Diffusion-reaction equations are used for modeling the mass balance between species in the venous wall. The main species considered to play a key role in the process of fibrosis are smooth muscle cells, endothelial cells, matrix metalloproteinases, vascular growth factors and the extracellular matrix. The developed model has been implemented on an idealized axisymmetric geometric vena cava model. Moreover, a sensitivity analysis has been performed to study the parameters influence on the evolution of the model. Results show that the computational model is able to predict the behavior of the species considered and it captures the key characteristics of lesion growth and the healing process within a vein subjected to non-physiological mechanical forces. Our results suggests that the vessel wall response is mainly caused by the endothelium denudation area and the collagen turnover among other factors.
下腔静脉滤器是一种植入下腔静脉的医疗器械，负责在血栓到达肺部之前捕获它们，预防肺栓塞。关于下腔静脉滤器的使用存在一些临床问题。其中之一是由于下腔静脉重塑导致取出装置时存在困难。在创建再现组织重塑的计算模型方面已经付出了巨大努力，但尚未关注下腔静脉中发生的纤维化现象。在这项工作中，提出了一种连续计算模型，该模型可再现抗血栓滤器存在时的纤维化情况。扩散反应方程用于模拟静脉壁中各物质之间的质量平衡。在纤维化过程中被认为起关键作用的主要物质是平滑肌细胞、内皮细胞、基质金属蛋白酶、血管生长因子和细胞外基质。所开发的模型已在理想化的轴对称几何下腔静脉模型上实现。此外，还进行了敏感性分析以研究参数对模型演变的影响。结果表明，该计算模型能够预测所考虑物质的行为，并捕捉到在承受非生理机械力的静脉内病变生长和愈合过程的关键特征。我们的结果表明，血管壁反应主要由内皮剥脱面积和胶原蛋白周转等因素引起。
