Mechanical Engineering, Koc University, Turkey.
Mechanical Engineering, Istinye University, Turkey.
J Biomech. 2021 Mar 5;117:110274. doi: 10.1016/j.jbiomech.2021.110274. Epub 2021 Jan 25.
Recent progress in vascular growth mechanics has involved the use of computational algorithms to address clinical problems with the use of three-dimensional patient specific geometries. The objective of this study is to establish a predictive computational model for the volumetric growth of pulmonary arterial (PA) tissue following complex cardiovascular patch reconstructive surgeries for congenital heart disease patients. For the first time in the literature, the growth mechanics and performance of artificial cardiovascular patches in contact with the growing PA tissue domain is established. An elastic-growing material model was developed in the open source FEBio software suite to first examine the surgical patch reconstruction process for an idealized main PA anatomy as a benchmark model and then for the patient-specific PA of a newborn. Following patch reconstruction, high levels of stress and strain are compensated by growth on the arterial tissue. As this growth progresses, the arterial tissue is predicted to stiffen to limit elastic deformations. We simulated this arterial growth up to the age of 18 years, when somatic growth plateaus. Our research findings show that the non-growing patch material remains in a low strain state throughout the simulation timeline, while experiencing high stress hot-spots. Arterial tissue growth along the surgical stitch lines is triggered mainly due to PA geometry and blood pressure, rather than due to material property differences in the artificial and native tissue. Thus, non-uniform growth patterns are observed along the arterial tissue proximal to the sutured boundaries. This computational approach is effective for the pre-surgical planning of complex patch surgeries to quantify the unbalanced growth of native arteries and artificial non-growing materials to develop optimal patch biomechanics for improved postoperative outcomes.
近年来，血管生长力学的研究进展涉及使用计算算法来解决使用三维患者特定几何形状的临床问题。本研究的目的是建立一个预测计算模型，用于预测先天性心脏病患者复杂心血管补片重建手术后肺动脉（PA）组织的体积生长。本文首次建立了与生长中的 PA 组织域接触的人工心血管补片的生长力学和性能。在开源 FEBio 软件套件中开发了一个弹性生长材料模型，首先以理想的主 PA 解剖结构作为基准模型来检查手术补片重建过程，然后以新生儿的特定 PA 进行检查。补片重建后，动脉组织的高应力和应变通过生长得到补偿。随着这种生长的进行，动脉组织被预测会变硬以限制弹性变形。我们模拟了这种动脉生长，直到 18 岁时体生长板达到峰值。我们的研究结果表明，在整个模拟时间内，非生长补片材料保持在低应变状态，同时经历高应力热点。沿着手术缝线的动脉组织生长主要是由于 PA 几何形状和血压引起的，而不是由于人工和天然组织之间的材料性能差异引起的。因此，在缝合边界附近的动脉组织近端观察到不均匀的生长模式。这种计算方法可有效用于复杂补片手术的术前规划，以量化天然动脉和人工非生长材料的不平衡生长，从而开发出最佳的补片生物力学，以改善术后结果。
