An arterio-venous fistula is a surgical procedure that supports access for people undergoing hemodialysis (HD) for End Stage Renal Disease (ESRD). This observational pilot study seeks to better understand the factors that contribute to the successful maturation of an arterio-venous fistula. A primary aim of this study is to see if endothelial function (the biochemical events initiated by cells lining the arteries) is associated with successful maturation. Other aims include determining if pro-inflammatory markers in the blood or evidence of gene expression are associated with successful maturation.
Current practice guidelines stipulate that 65% of all prevalent ESRD patients should receive HD through some sort of arterio-venous fistula (AVF). An AVF is a subcutaneous, permanent vascular access created surgically by connecting a vein with an artery and is the preferred mode of access due to lower rates of infection or thrombosis compared to prosthetic grafts or tunneled lines. An AVF is mature if it can sustain high quality HD. However, rates of primary failure (the inability of an AVF to sustain HD) are high, ranging from 40-70%. Traditional coronary risk factors such as hypertension, hypercholesterolemia, and diabetes mellitus, have limited ability to allow surgeons to predict which AVFs will mature.
One possible explanation involves vascular remodeling, the structural changes which occur in a blood vessel in response to hemodynamic stimuli. The endothelial, lying at the interface of the vessel wall and flowing blood, is a "biosensor", responding to changes in blood flow and pressure. It initiates a complex biological response including cellular proliferation and migration, matrix degradation, and cellular apoptosis. This longitudinal, observational study hypothesizes that endothelial function is a critical modulator of AVF maturation. Specifically, that patients with inflammation will have impaired endothelial function and demonstrate less significant remodeling than others.