Arteriovenous fistulae are created surgically to provide an adequate access for dialysis in patients with End-Stage Renal Disease (ESRD). Producing an autogenous shunt linking an artery and a vein in the peripheral circulation bypasses the high resistance capillary bed in order to provide the necessary flow rates at sites easily accessible for dialysis. It has long been recognized that hemodynamics constitute the primary external influence on the remodeling process of anastomosed vascular tissue [1, 2]. The high flow rate, together with the exposure of the venous tissue to the high arterial pressure, leads to a rapid process of wall remodeling that may lead to a mature access or end in failure. Recent hemodynamic simulations [3, 4] have computed very high viscous wall shear stresses within dialysis access fistulae; Stresses >15 Pa have been reported. These are much higher than what is typically considered normal or homeostatic (i.e. ≈ 1–1.5 Pa). The abnormal stresses in the fistulae have been hypothesized to cause pathological venous remodeling (i.e. intimal hyperplasia) which causes stenoses and threatens fistula patency. Given the high failure rate of dialysis access sites (up to 50% require surgical revision within one year), understanding the dynamics of blood flow within the fistula is a necessary step in understanding remodeling, and ultimately, in improving clinical outcomes.

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