Jiang Xudong, Cao Haoyao, Zhang Zijian, Zheng Tinghui, Li Xiaoqiang, Wu Peng
Artificial Organ Technology Laboratory, School of Mechanical and Electric Engineering, Soochow University, Suzhou, China.
Department of Vascular Surgery, Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
Front Physiol. 2022 May 23;13:906502. doi: 10.3389/fphys.2022.906502. eCollection 2022.
The aim of this study is to numerically evaluate thrombosis risk within occluded coronary arterial fistulas (CAF) with terminal aneurysms, and provide guidance in choosing occlusion positions, with clinical observations as reference. Four patients with CAF were studied, with different occlusion positions in actual treatments. Hemodynamics simulations were conducted, with blood residue predicted using the blood stasis model. Three types of models (untreated model, aneurysm-reserved model and aneurysm-removed model) were studeid for each patient. Four metrics, i.e., proportion of high oscillatory shear index (OSI), area of high OSI, old blood volume fraction (OBVF)) and old blood volume (OBV) was obtained to distinguish the thrombosis risk of different treatments (proximal or distal occlusion), comparing with the follow-up CTA. For all the postopertive models, the high OBVF, high OSI(>0.3) and low time-averaged wall shear stress (TAWSS) regions were mainly at the distal fistula, indicating these regions were prone to thrombosis. The regions where blood residue remains are roughly regions of high OSI, corresponding well with clinical observations. In contrast, TAWSS failed to distinguish the difference in thrombosis risk. Absolute values (area of high OSI, OBV) can better reflect the degree of thrombosis risk between treatment types compared with percentage values (proportion of high OSI, OBVF). By comparing with the actual clinical treatments and observations, the OBV is superior to the area of high OSI in determining treatment type. The OBV, a volumetric parameter for blood stasis, can better account for the CAF thrombosis and reflect the degree of blood stasis compared with OSI or TAWSS, is a more appropriate metric for thrombosis in the fistula. Together with morphological parameters, the OBV could guide clinicians to formulate more appropriate surgical plans, which is of great significance for the preoperative evaluation and treatment prognosis of CAF patients.
本研究旨在通过数值模拟评估伴有终末动脉瘤的闭塞性冠状动脉瘘（CAF）内的血栓形成风险，并以临床观察为参考，为选择闭塞位置提供指导。研究了4例CAF患者，其在实际治疗中有不同的闭塞位置。进行了血流动力学模拟，使用血流淤滞模型预测血液残留情况。对每位患者研究了三种类型的模型（未治疗模型、保留动脉瘤模型和切除动脉瘤模型）。获得了四个指标，即高振荡剪切指数（OSI）比例、高OSI区域面积、陈旧血液体积分数（OBVF）和陈旧血液体积（OBV），以区分不同治疗方法（近端或远端闭塞）的血栓形成风险，并与随访CTA进行比较。对于所有术后模型，高OBVF、高OSI（>0.3）和低时间平均壁面剪切应力（TAWSS）区域主要位于瘘管远端，表明这些区域易发生血栓形成。血液残留的区域大致是高OSI区域，与临床观察结果吻合良好。相比之下，TAWSS未能区分血栓形成风险的差异。与百分比值（高OSI比例、OBVF）相比，绝对值（高OSI区域面积、OBV）能更好地反映不同治疗类型之间的血栓形成风险程度。通过与实际临床治疗和观察结果进行比较，在确定治疗类型方面，OBV优于高OSI区域面积。OBV作为一种血流淤滞的体积参数，与OSI或TAWSS相比，能更好地解释CAF血栓形成并反映血流淤滞程度，是瘘管血栓形成更合适的指标。结合形态学参数，OBV可指导临床医生制定更合适的手术方案，这对CAF患者的术前评估和治疗预后具有重要意义。
