Growth and remodeling in arterial tissue have attracted considerable attention over the last decade. Mathematical models have been proposed, and computational studies with these have helped to understand the role of the different model parameters. So far it remains, however, poorly understood how much of the model output variability can be attributed to the individual input parameters and their interactions. To clarify this, we propose herein a global sensitivity analysis, based on Sobol indices, for a homogenized constrained mixture model of aortic growth and remodeling. In two representative examples, we found that 54–80% of the long term output variability resulted from only three model parameters. In our study, the two most influential parameters were the one characterizing the ability of the tissue to increase collagen production under increased stress and the one characterizing the collagen half-life time. The third most influential parameter was the one characterizing the strain-stiffening of collagen under large deformation. Our results suggest that in future computational studies it may - at least in scenarios similar to the ones studied herein - suffice to use population average values for the other parameters. Moreover, our results suggest that developing methods to measure the said three most influential parameters may be an important step towards reliable patient-specific predictions of the enlargement of abdominal aortic aneurysms in clinical practice.

在过去的十年中，动脉组织的生长和重塑引起了相当大的关注。已经提出了数学模型，并且对这些模型的计算研究有助于理解不同模型参数的作用。但是，到目前为止，仍然很少了解模型输出的可变性可归因于各个输入参数及其相互作用。为了澄清这一点，我们在此提出基于Sobol指数的全局敏感性分析，用于主动脉生长和重塑的均质约束混合模型。在两个有代表性的例子中，我们发现长期输出可变性的54–80％仅来自三个模型参数。在我们的研究中 最具影响力的两个参数是表征组织在压力增加下增加胶原蛋白生成能力的一个参数，以及表征胶原蛋白半衰期的一个参数。第三个最具影响力的参数是表征大变形下胶原的应变刚度的参数。我们的结果表明，在将来的计算研究中-至少在与本文研究的场景类似的情况下-可以使用总体平均值作为其他参数。而且，我们的结果表明，开发用于测量所述三个最有影响力的参数的方法可能是朝着临床实践中可靠的针对患者的腹主动脉瘤扩大预测的重要一步。第三个最具影响力的参数是表征大变形下胶原的应变刚度的参数。我们的结果表明，在将来的计算研究中-至少在与本文研究的场景类似的情况下-可以使用总体平均值作为其他参数。而且，我们的结果表明，开发用于测量所述三个最有影响力的参数的方法可能是朝着临床实践中可靠的针对患者的腹主动脉瘤扩大预测的重要一步。第三个最具影响力的参数是表征大变形下胶原的应变刚度的参数。我们的结果表明，在将来的计算研究中-至少在与本文研究的场景类似的情况下-可以使用总体平均值作为其他参数。而且，我们的结果表明，开发用于测量所述三个最有影响力的参数的方法可能是朝着临床实践中可靠的针对患者的腹主动脉瘤扩大预测的重要一步。