Hemodynamic Shear Stress and Endothelial Dysfunction in Hemodialysis Access

Area of Science:

• Vascular biology
• Biomedical engineering
• Nephrology

Background:

• Chronic hemodialysis relies on surgically created arteriovenous fistulas (AVFs) and grafts (AVGs).
• AVFs often fail to mature, while AVGs are prone to stenosis caused by neointimal hyperplasia at the anastomosis.
• Current therapies to improve AVF maturation or prevent AVG stenosis are lacking.

Purpose of the Study:

• To review the roles of fluid-wall shear stress (WSS) and endothelial cells (ECs) in arteriovenous access pathology.
• To elucidate the mechanisms underlying AVF non-maturation and AVG stenosis.
• To discuss methods for assessing hemodynamics and EC responses in AV access.

Main Methods:

• Review of existing literature on hemodynamics, WSS, and EC biology in AV access.
• Analysis of how altered blood flow impacts vascular geometry and cellular responses.
• Discussion of methods for characterizing blood flow and calculating WSS.

Main Results:

• Altered hemodynamics from shunting arterial blood into veins significantly impact AV access.
• Aberrant WSS and subsequent EC responses are implicated in AVF non-maturation and AVG stenosis.
• Confounding factors modulate the effects of WSS on arteriovenous access pathology.

Conclusions:

• Understanding the interplay between hemodynamics, WSS, and ECs is crucial for addressing AV access complications.
• Targeting WSS-mediated EC responses may offer novel therapeutic strategies.
• Further research into modulating these factors could improve outcomes for kidney failure patients.