A recent study that was published in The American Journal of Pathology, provides information about the mechanisms underlying failure of the most common type of hemodialysis vascular access, the arteriovenous fistula. In spite of AV Fistula being one of the most preferred methods of Vascular access, the researchers observed that, up to 60% of newly created fistulas never become usable for dialysis because they fail to mature (meaning the vessels do not enlarge enough to support the dialysis blood circuit.). This study suggests that, the impairment in responsiveness to nitric oxide that occurs in some patients with end-stage renal disease may result in hyperplasia (excessive growth) of the innermost layer of the blood vessels or reduced ability of the vessels to dilate. Either abnormality can limit the maturation and viability of the arteriovenous fistula. This research raises the possibility that therapeutic restoration of nitric oxide responsiveness through manipulation of local mediators may prevent fistula maturation failure in patients and potentially contribute to their ability to remain on hemodialysis.