Pathophysiology of High Flow Access and Surgical Flow Reduction Procedures

High flow access (HFA) is a condition in which hemodynamics is affected by a flow rate that is larger than the blood flow required for hemodialysis. HFA sometimes causes high output heart failure, venous hypertension, and dialysis access steal syndrome. Flow reduction is effective for improving symptoms, and various surgical procedures have been reported. HFA is recognized as a well-developed type of access due to its good access sound, thrill, and vessel diameter; also, HFA probably has good patency if not intervened with by flow reduction. Therefore, the blood flow reduction procedures used to treat HFA need to minimize disadvantages such as access thrombosis, insufficient blood flow, aneurysm formation, and infection due to therapeutic intervention while, at the same time, achieving symptom improvement and long-term patency. The surgical procedure used to correct HFA must be highly reproducible and simple. This article reviews the pathophysiology and surgical flow reduction procedures for HFA.