In-stent restenosis (ISR) after percutaneous coronary intervention is a multi-factorial process. Specific morphological lesion characteristics were observed to contribute to the occurrence of ISR. Local mechanical factors, such as stresses and strains, are known to influence tissue adaptation after stent implantation. However, the influence of morphological features on those local mechanical states and, hence, on the occurrence of ISR remains understudied. This work explores how local mechanical quantities relate to ISR by evaluating the stress distributions in the artery wall during and after stent implantation for morphology-informed lesion examples. We perform computational simulations of the stenting procedure with physics-based patient-specific coronary artery models. Different morphologies are assessed using the spatial plaque composition information from high-resolution coronary computed tomography angiography data. In the sample cases, elevated local tensile stresses were consistently found at sites corresponding to ISR. We found that specific morphological characteristics like circumferential or asymmetric block calcifications result in higher stresses in the surrounding tissue. These findings show that for the observed connection between plaque morphology and ISR, the local mechanical state may represent a relevant link. This study provides a mechanistic, illustrative insight for the examined cases. Future work with larger cohorts and systematic follow-up can establish statistically robust associations.

翻译：经皮冠状动脉介入治疗后的支架内再狭窄（ISR）是一个多因素过程。研究发现特定的形态学病变特征会影响ISR的发生。已知局部力学因素（如应力和应变）会影响支架植入后的组织适应性。然而，形态学特征对这些局部力学状态的影响及其对ISR发生的作用仍未得到充分研究。本研究通过评估基于形态学特征的病变示例在支架植入期间及之后动脉壁的应力分布，探讨局部力学量与ISR的关联。我们采用基于物理原理的患者特异性冠状动脉模型对支架植入过程进行了计算模拟。利用高分辨率冠状动脉计算机断层扫描血管造影数据提供的空间斑块成分信息，对不同形态特征进行了评估。在示例病例中，始终发现与ISR对应的位置存在局部拉伸应力升高。研究发现特定的形态特征（如环形或不对称的块状钙化）会导致周围组织承受更高的应力。这些结果表明，在观察到的斑块形态与ISR之间的关联中，局部力学状态可能构成重要的联系环节。本研究为所考察的病例提供了机制性的图示化解析。未来通过更大规模队列研究和系统性随访，可建立具有统计学稳健性的关联。