Krishnamoorthy Mahesh K, Banerjee Rupak K, Wang Yang, Zhang Jianhua, Sinha Roy Abhijit, Khoury Saeb F, Arend Lois J, Rudich Steve, Roy-Chaudhury Prabir
Cincinnati Dialysis Access Research Program, Department of Mechanical, Industrial, and Nuclear Engineering, University of Cincinnati, Cincinnati, Ohio 45267-0585, USA.
Kidney Int. 2008 Dec;74(11):1410-9. doi: 10.1038/ki.2008.379. Epub 2008 Sep 24.
Venous stenosis is a significant problem in arteriovenous fistulae, likely due to anatomical configuration and wall shear stress profiles. To identify linkages between wall shear stress and the magnitude and pattern of vascular stenosis, we produced curved and straight fistulae in a pig model. A complete wall stress profile was calculated for the curved configuration and correlated with luminal stenosis. Computer modeling techniques were then used to derive a wall shear stress profile for the straight arteriovenous fistula. Differences in the wall shear stress profile of the curved and straight fistula were then related to histological findings. There was a marked inverse correlation between the magnitude of wall shear stress within different regions of the curved arteriovenous fistula and luminal stenosis in these same regions. There were also significantly greater differences in wall shear stress between the outer and inner walls of the straight as compared to curved arteriovenous fistula, which translated into a more eccentric histological pattern of intima-media thickening. Our results suggest a clear linkage between anatomical configuration, wall shear stress profiles, and the pattern of luminal stenosis and intima-media thickening in a pig model of arteriovenous fistula stenosis. These results suggest that fistula failure could be reduced by using computer modeling prior to surgical placement to alter the anatomical and, consequently, the wall shear stress profiles in an arteriovenous fistula.
静脉狭窄是动静脉内瘘的一个重要问题，可能是由于解剖结构和壁面剪应力分布所致。为了确定壁面剪应力与血管狭窄程度及模式之间的联系，我们在猪模型中制作了弯曲和直的内瘘。计算了弯曲结构的完整壁面应力分布，并将其与管腔狭窄相关联。然后使用计算机建模技术得出直动静脉内瘘的壁面剪应力分布。接着将弯曲和直内瘘壁面剪应力分布的差异与组织学结果相关联。在弯曲动静脉内瘘的不同区域，壁面剪应力大小与这些相同区域的管腔狭窄之间存在明显的负相关。与弯曲动静脉内瘘相比，直动静脉内瘘的外壁和内壁之间的壁面剪应力差异也显著更大，这转化为内膜 - 中膜增厚的更偏心组织学模式。我们的结果表明，在猪动静脉内瘘狭窄模型中，解剖结构、壁面剪应力分布与管腔狭窄模式及内膜 - 中膜增厚之间存在明确的联系。这些结果表明，在手术放置前使用计算机建模来改变动静脉内瘘的解剖结构，进而改变壁面剪应力分布，可能会减少内瘘失败。
