Department of Vascular Surgery, Rijnstate Hospital, Arnhem, The Netherlands.
Physics of Fluids Group, TechMed Centre, University of Twente, Drienerlolaan 5, 7522 NB, Enschede, The Netherlands.
Cardiovasc Intervent Radiol. 2022 Jun;45(6):858-866. doi: 10.1007/s00270-022-03118-x. Epub 2022 Apr 4.
The feasibility of using a compressed interwoven Supera stent as a flow diverting device for popliteal aneurysms was recently demonstrated in patients. It is unclear, however, what the optimal flow diverting strategy is, because of the fusiform shape of popliteal aneurysms and their exposure to triphasic flow. To assess this flow diverting strategy for popliteal aneurysms, flow profiles and thrombus formation likelihood were investigated in popliteal aneurysm models.
Six popliteal aneurysm models were created and integrated into a pulsatile flow set-up. These models covered a bent and a straight anatomy in three configurations: control, single-lined and dual-lined Supera stents. Two-dimensional flow velocities were visualized by laser particle image velocimetry. In addition, the efficacy of the stent configurations for promoting aneurysm thrombosis was assessed by simulations of residence time and platelet activation.
On average for the two anatomies, the Supera stent led to a twofold reduction of velocities in the aneurysm for single-lined stents, and a fourfold reduction for dual-lined stents. Forward flow was optimally diverted, whereas backward flow was generally deflected into the aneurysm. The dual-lined configuration led to residence times of 15-20 s, compared to 5-15 s for the single stent configurations. Platelet activation potential was not increased by the flow diverting stents.
A compressed Supera stent was successfully able to divert flow in a popliteal aneurysm phantom. A dual-lined configuration demonstrated superior hemodynamic characteristics compared to its single-lined counterpart.
最近有研究人员在患者中证实，使用压缩编织的 Supera 支架作为治疗腘动脉瘤的血流转向装置具有可行性。然而，由于腘动脉瘤呈梭形且存在三相血流，因此血流转向策略并不明确。为了评估该血流转向策略在治疗腘动脉瘤中的效果，研究人员在腘动脉瘤模型中对血流形态和血栓形成的可能性进行了研究。
研究共创建了 6 个腘动脉瘤模型，并将其整合到脉动流装置中。这些模型覆盖了弯曲和直两种解剖结构，分别采用了三种配置：对照组、单一线型 Supera 支架和双线性 Supera 支架。采用激光粒子图像测速法对二维流速进行可视化。此外，还通过模拟驻留时间和血小板激活来评估支架构型对促进动脉瘤血栓形成的效果。
对于两种解剖结构，平均而言，单一线型支架可使动脉瘤内的流速降低两倍，双线性支架则降低四倍。正向血流得到了最佳的转向，而反向血流通常被转向到动脉瘤中。与单一线型支架相比，双线性支架的驻留时间为 15-20s，而单一线型支架的驻留时间为 5-15s。血流转向支架并没有增加血小板的激活潜能。
压缩后的 Supera 支架可成功地将血流转向腘动脉瘤模型。与单一线型支架相比，双线性支架的血流动力学特征更优。
