Assessing Radiocephalic Wrist Arteriovenous Fistulas of Obtuse Anastomosis using Computational Fluid Dynamics and Clinical Application

Abstract

An obtuse radiocephalic wrist AVF shows more favorable patency compared to a classic radiocephalic AVF. Surgeons establishing a radiocephalic wrist AVF would be better to consider an AVF with an obtuse anastomosis.

Reduction in anastomotic flow disturbance within a modified end‐to‐side arteriovenous fistula configuration: Results of a computational flow dynamic model

“…Lee et al . examined results from a single‐centre where 201 patients underwent the creation of radio‐cephalic AVFs over a five‐year period . Those AVFs were divided into acute‐ and obtuse‐angle (similar to our smooth‐loop) groups for comparison.…”

“…Lee et al examined results from a single-centre where 201 patients underwent the creation of radio-cephalic AVFs over a five-year period. 11 Those AVFs were divided into acute-and obtuse-angle (similar to our smooth-loop) groups for comparison. They found the obtuse-angle had superior primary patency rates of 59.8% and 53.2% at 12-and 24-months, respectively, compared to 54.6% and 45.7% for the standard, acute-angle configuration.…”

Numerical simulation of blood fluid in hemodialysis catheters and its thrombogenic potential

“…Recirculation creates a variation in shear stress and velocity values and, consequently, a disorder in the direction of blood flow (Lucas et al, 2014, Peng et al, 2017. This process contributes to the progression of the coagulation cascade mediated by the endothelial cells of the vein, since it changes the morphology and functions of these cells (Sarmast, Niroomand-Oscuii, Ghalichi & Samiei, 2014;Lee et al, 2016). Between the lateral orifices, there was also the presence of vortex, circular pattern of the blood flow.…”

“…The shear stress is the frictional force of blood flow that acts on the vessel wall and can be detected directly in an endothelial cell on the luminal surface (Peng et al, 2017). It is fully believed that abnormal shear stress is an important reason for initiation and formation of thrombus (Peng et al, 2017;Lee et al, 2016).…”

“…A study in China that performed a numerical simulation of CVC inserted into the vein found that maintaining the catheter within the vein led to a significant increase in pressure and an abnormally high shear stress in the vessel wall (Peng et al, 2017). The term 'abnormally high' refers to the physiological comparison of shear stress within the vein without the CVC ranging from 0.1 to 1 Pa (Peng et al, 2017;Lee et al, 2016, Dydek, & Chaikof, 2016. However, that study did not construct the actual CVC geometry with the lateral orifices and the central division within the catheter.…”