ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland.
Clinical and Interventional Angiology, Vascular Institute Central Switzerland, Aarau, Switzerland.
Biomech Model Mechanobiol. 2019 Dec;18(6):1883-1893. doi: 10.1007/s10237-019-01183-9. Epub 2019 Jun 13.
Endovascular therapy in patients suffering from peripheral arterial disease shows high rates of restenosis. The poor clinical outcomes are commonly explained by the demanding mechanical environment due to leg movements, but the mechanisms responsible for restenosis remain unknown. In this study, we hypothesized that restenosis following revascularization is associated with hemodynamical markers derived from blood flow during leg flexion. Therefore, we performed personalized computational fluid dynamics (CFD) analyses of 20 patients, who underwent routine endovascular femoro-popliteal interventions. The CFD analyses were conducted using 3D models of the arterial geometry in straight and flexed positions, which were reconstructed from 2D angiographic images. Based on restenosis rates reported at 6-month follow-up, logistic regression analyses were performed to predict restenosis from hemodynamical parameters. Results showed that severe arterial deformations, such as kinking, induced by leg flexion in stented arteries led to adverse hemodynamic conditions that may trigger restenosis. A logistic regression analysis based solely on hemodynamical markers had an accuracy of 75%, which showed that flow parameters are sufficient to predict restenosis (p = 0.031). However, better predictions were achieved by adding the treatment method in the model. This suggests that a more accurate image acquisition technique is required to capture the localized modifications of blood flow following intervention, especially around the stented artery. This approach, based on the immediate postoperative configuration of the artery, has the potential to identify patients at increased risk of restenosis. Based on this information, clinicians could take preventive measures and more closely follow these patients to avoid complications.
血管内治疗在外周动脉疾病患者中显示出较高的再狭窄率。下肢运动导致的苛刻力学环境通常解释了较差的临床结果,但再狭窄的机制仍不清楚。在这项研究中,我们假设血管再通后再狭窄与腿部弯曲时血流产生的血流动力学标志物有关。因此,我们对 20 名接受常规血管内股腘治疗的患者进行了个性化的计算流体动力学(CFD)分析。CFD 分析使用直腿和弯曲位的动脉几何形状的 3D 模型进行,这些模型是从 2D 血管造影图像重建而来的。根据 6 个月随访时报告的再狭窄率,进行逻辑回归分析以从血流动力学参数预测再狭窄。结果表明,腿部弯曲导致支架内动脉严重的动脉变形,如扭曲,导致不良的血流动力学条件,可能引发再狭窄。仅基于血流动力学标志物的逻辑回归分析的准确性为 75%,表明血流参数足以预测再狭窄(p=0.031)。然而,通过在模型中添加治疗方法可以获得更好的预测。这表明需要更精确的图像采集技术来捕捉介入后血流的局部变化,特别是在支架内动脉周围。这种基于动脉术后即刻形态的方法有可能识别出再狭窄风险增加的患者。基于这些信息,临床医生可以采取预防措施并更密切地随访这些患者以避免并发症。