Carroll John, Varcoe Ramon L, Barber Tracie, Simmons Anne
School of Mechanical and Manufacturing Engineering, University of New South Wales, Australia.
Department of Surgery, Prince of Wales Hospital, Sydney, Australia.
Nephrology (Carlton). 2019 Feb;24(2):245-251. doi: 10.1111/nep.13219.
We sought to determine if a modification to the peri-anastomotic vein configuration during end-to-side arteriovenous fistula (AVF) creation would achieve a favourable haemodynamic environment compared with the standard acute-angle AVF.
Computational fluid dynamics (CFD) modelling of two end-to-side AVF geometries (smooth-vein-loop vs. acute-angle) allowed for haemodynamic modelling. Haemodynamic fields at various stages of the pulse cycle were observed and compared across both models.
We found a significant reduction in flow disturbance in the modified shape at the peri-anastomotic vein region, a common site for stenosis. The acute anastomotic angle characteristic of a standard-end-to-side AVF was found to cause significant flow disturbance throughout the pulse cycle.
Computational modelling indicates that improvements in the haemodynamic environment of an AVF are achievable when a gentle change in direction is present in the vein segment. This may lead to improved maturation and AVF patency through reduction in disturbed flow patterns.
我们试图确定在端侧动静脉内瘘（AVF）创建过程中，对吻合口周围静脉构型进行改良是否会比标准锐角AVF实现更有利的血流动力学环境。
对两种端侧AVF几何形状（平滑静脉环与锐角）进行计算流体动力学（CFD）建模，以进行血流动力学建模。观察并比较两个模型在脉搏周期各个阶段的血流动力学场。
我们发现，在吻合口周围静脉区域（狭窄的常见部位），改良形状的血流紊乱显著减少。标准端侧AVF的急性吻合角特征被发现会在整个脉搏周期引起显著的血流紊乱。
计算建模表明，当静脉段方向存在轻微变化时，AVF的血流动力学环境可得到改善。这可能通过减少紊乱的血流模式而导致更好的成熟度和AVF通畅率。
