Biological and Physical Factors Involved in the Maturation of Arteriovenous Fistula for Hemodialysis

One of the most important limitations of hemodialysis (HD) treatment is the vascular access (VA) that is used to connect the patient’s blood vessels to the extracorporeal circulation. The arteriovenous fistula (AVF) obtained with native vessels is the VA of choice for the low incidence of infections and the long-term patency, but it is affected by high incidence of non-maturation or primary failure. Before use for cannulation, AVF must undergo vascular remodeling, with progressive increase in vessel diameter, to accommodate the increase in blood flow. A growing body of evidence indicates that AVF maturation is related to the response of endothelial cells to changes in blood flow and wall shear stress. In the present report we examine the experimental and clinical evidences on the mechanisms that play a role in vascular remodeling during AVF maturation. The physical and biological factors that develop upon arteriovenous surgical connection affect endothelial and smooth muscle cell function, as well as extracellular matrix remodeling. They can explain to a great extent the process of vascular remodeling and put more light on cellular mechanisms of vessel wall adaptation. The understanding of these phenomena, besides indicating the reasons for non-maturation and primary failure, may be fundamental in the future to ameliorate clinical outcomes of AVF creation, with a great impact on the clinical management of HD patients and their quality of life.