Abstract: SA-PO013
Comparison of Local Hemodynamics in Rat Arteriovenous Fistula With and Without Accessory Vein
Session Information
- Bioengineering
November 05, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
Abstract Time: 10:00 AM - 12:00 PM
Category: Bioengineering
- 300 Bioengineering
Authors
- Chen, Britney, The University of Utah, Salt Lake City, Utah, United States
- Fairbourn, Brayden, The University of Utah, Salt Lake City, Utah, United States
- Northrup, Hannah M., The University of Utah, Salt Lake City, Utah, United States
- Lee, Timmy C., The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Shiu, Yan-Ting Elizabeth, The University of Utah, Salt Lake City, Utah, United States
Background
Arteriovenous fistula (AVF) maturation failure is a major clinical problem. AVF hemodynamics are a significant factor in regulating AVF remodeling and maturation, but our understanding of the precise hemodynamics in the AVF is not yet complete. The presence of accessory veins (i.e., vein branches from the primary venous limb of an AVF) may decrease blood flow through the fistula and consequently contribute to AVF maturation failure. Therefore, in patients, accessory veins may be ligated at the time of AVF creation. Here we investigate the effects of accessory veins on AVF hemodynamics in a rat model.
Methods
Femoral AVFs were created in 12 to 16-week-old male Sprague-Dawley mice. MRI scans taken 21 days after AVF creation were used to create reconstructions of the AVF lumen with and without an accessory vein (n = 3). The reconstructions were then used, together with MRI-measured velocities, in computational fluid dynamic (CFD) simulations. Hemodynamic parameters (velocity, wall shear stress (WSS), vorticity, and oscillatory shear index (OSI)) were calculated for the AVF vein segment starting from the anastomosis and ending at the location immediately prior to the vein branch and an equivalent proximal artery segment.
Results
The AVF vein WSS result with and without an accessory vein was similar (247.1 ± 291.8 vs. 190.0 ± 195.1 dynes/cm2; p > 0.05). The AVF vein OSI result with and without the accessory vein was also similar (0.06 ± 0.06 vs. 0.08 ± 0.06; p > 0.05). However, the AVF vein vorticity with and without an accessory vein (3569.9 ± 4381.9 vs. 2711.5 ± 3145.4 1/s) and AVF vein velocity with and without an accessory vein (65.9 ± 64.1 vs. 53.6 ± 50.6 cm/s) were significantly different (p < 0.05). The proximal artery WSS, OSI, vorticity, and velocity were similar between the AVFs with and without an accessory vein (p > 0.05).
Conclusion
Except for vorticity and velocity in the AVF vein, the hemodynamics between AVFs with and without accessory veins were largely similar. Including accessory veins when analyzing AVF hemodynamics in CFD simulations may result in some different hemodynamic parameters. Future research will investigate whether these differences are associated with AVF maturation failure.
Funding
- NIDDK Support