Mirgolbabaee Hadi, van de Velde Lennart, Geelkerken Robert H, Versluis Michel, Groot Jebbink Erik, Reijnen Michel M P J
Multi-Modality Medical Imaging Group, Technical Medical Centre, University of Twente, Enschede, The Netherlands.
Physics of Fluids Group, Technical Medical Centre, University of Twente, Enschede, The Netherlands.
J Endovasc Ther. 2023 Dec 27:15266028231219988. doi: 10.1177/15266028231219988.
To identify potential hemodynamic predictors for limb thrombosis (LT) following endovascular aneurysm repair with the Anaconda endograft in a patient-specific phantom.
A thin-walled flow phantom, based on a patient's aortic anatomy and treated with an Anaconda endograft, that presented with a left-sided LT was fabricated. Contrast-enhanced ultrasound particle image velocimetry was performed to quantify time-resolved velocity fields. Measurements were performed in the same phantom with and without the Anaconda endograft, to investigate the impact of the endograft on the local flow fields. Hemodynamic parameters, namely vector complexity (VC) and residence time (RT), were calculated for both iliac arteries.
In both limbs, the vector fields were mostly unidirectional during the peak systolic and end-systolic velocity phases before and after endograft placement. Local vortical structures and complex flow fields were observed at the diastolic and transitional flow phases. The average VC was higher (0.11) in the phantom with endograft, compared to the phantom without endograft (0.05). Notably, in both left and right iliac arteries, the anterior wall regions corresponded to a 2- and 4-fold increase in VC in the phantom with endograft, respectively. RT simulations showed values of 1.3 to 6 seconds in the phantom without endograft. A higher RT (up to 25 seconds) was observed in the phantom with endograft, in which the left iliac artery, with LT in follow-up, showed 2 fluid stasis regions.
This in vitro study shows that unfavorable hemodynamics were present mostly in the limb that thrombosed during follow-up, with the highest VC and longest RT. These parameters might be valuable in predicting the occurrence of LT in the future.
This in-vitro study aimed to identify potential hemodynamic predictors for limb thrombosis following EVAR using ultrasound particle image velocimetry (echoPIV) technique. It was shown that unfavorable hemodynamic norms were present mostly in the thrombosed limb. Owing to the in-vivo feasibility of the echoPIV, future efforts should focus on the evaluation of these hemodynamic norms in clinical trials. Thereafter, using echoPIV as a bedside technique in hospitals becomes more promising. Performing echoPIV in pre-op phase may provide valuable insights for surgeons to enhance treatment planning. EchoPIV is also applicable for follow-up sessions to evaluate treatment progress and avoid/predict complications.
在特定患者的模型中，确定使用Anaconda血管内移植物进行血管内动脉瘤修复术后肢体血栓形成（LT）的潜在血流动力学预测指标。
制作一个基于患者主动脉解剖结构并植入Anaconda血管内移植物的薄壁血流模型，该模型出现了左侧LT。采用对比增强超声粒子图像测速技术来量化时间分辨速度场。在有和没有Anaconda血管内移植物的同一模型中进行测量，以研究血管内移植物对局部流场的影响。计算双侧髂动脉的血流动力学参数，即矢量复杂性（VC）和停留时间（RT）。
在血管内移植物植入前后的收缩期峰值和收缩期末速度阶段，双侧肢体的矢量场大多为单向。在舒张期和过渡流阶段观察到局部涡旋结构和复杂流场。与没有血管内移植物的模型（0.05）相比，有血管内移植物的模型中平均VC更高（0.11）。值得注意的是，在左、右髂动脉中，有血管内移植物的模型中前壁区域的VC分别增加了2倍和4倍。RT模拟显示，没有血管内移植物的模型中的值为1.3至6秒。在有血管内移植物的模型中观察到更高的RT（高达25秒），其中随访中出现LT的左髂动脉显示有2个血流淤滞区域。
这项体外研究表明，不利的血流动力学主要存在于随访期间发生血栓形成的肢体中，其VC最高且RT最长。这些参数可能对未来预测LT的发生有价值。
这项体外研究旨在使用超声粒子图像测速（echoPIV）技术确定血管内动脉瘤修复术后肢体血栓形成的潜在血流动力学预测指标。结果表明，不利的血流动力学指标主要存在于发生血栓的肢体中。由于echoPIV在体内的可行性，未来的努力应集中在临床试验中对这些血流动力学指标的评估上。此后，在医院将echoPIV作为床边技术使用变得更有前景。在术前阶段进行echoPIV可为外科医生加强治疗规划提供有价值的见解。echoPIV也适用于随访阶段，以评估治疗进展并避免/预测并发症。
