Optimizing arteriovenous fistula (AVF) configurations: a computational study of radial artery deviation and reimplantation (RADAR) and conventional techniques in hemodynamics

OBJECTIVES: Anastomotic stenosis in arteriovenous fistulas (AVFs) is a significant issue for hemodialysis patients. This study uses computational fluid dynamics (CFD) simulations to evaluate the effects of different AVF configurations, comparing the RADAR technique with conventional AVF configurations in terms of hemodynamics, flow disturbances, and wall shear stress (WSS). METHODS: Echo-color Doppler (ECD) imaging and CFD simulations assessed disturbed hemodynamics in different AVF configurations. Large eddy simulations (LES) captured turbulence transition at the anastomosis. Hemodynamic parameters, including velocity distribution, vortex formation, WSS, wall displacement, and stress distribution, were analyzed. A one-way fluid-structure interaction (FSI) approach was used to compute fluid-induced wall forces and assess stress distribution and deformation. RESULTS: The RADAR configuration showed superior hemodynamic performance with higher blood flow velocity, reduced turbulence, and a more favorable WSS environment, potentially reducing stenosis risk and improving long-term patency. Higher venous inner wall stress in RADAR configurations may aid vascular remodeling. CONCLUSIONS: Optimizing AVF configurations and anastomosis angles can enhance AVF functionality, reduce complications, and improve hemodialysis outcomes for patients with end-stage renal disease. The RADAR technique may improve AVF maturation and reduce complications.