Arteriovenous Fistula Thrombosis

Introduction to AVF Thrombosis

Arteriovenous fistulas can and do clot, representing one of the primary causes of vascular access failure in hemodialysis patients, according to the American Journal of Kidney Diseases and the Journal of the American College of Radiology 1, 2

The primary precipitator of thrombosis is stenosis that develops secondary to neointimal hyperplasia, which increases pressure within the access and decreases blood flow, as stated by the Journal of the American College of Radiology 2
If hemodynamically significant stenosis is left untreated, it will result in thrombosis of the access, according to the Journal of the American College of Radiology 2

AVF thrombosis falls under the category of "thrombotic flow-related complications or dysfunction," which includes events exclusively related to thrombus formation that causes a clinically important decrease in intra-access flow, as classified by the Journal of the American College of Radiology and the American College of Radiology 2, 4
Heralding signs of impending thrombosis include changes in the access thrill or bruit, prolonged bleeding after decannulation post-dialysis, or arm swelling, as reported by the Journal of the American College of Radiology 2
Regular monitoring through physical examination and surveillance using device-based methods to assess blood access flow rate, access recirculation, and dialysis venous pressure helps detect stenosis before thrombosis occurs, according to the Journal of the American College of Radiology 2

Thrombosed fistulae should be treated as soon as possible after detection to increase the likelihood of successful restoration and avoid temporary catheter placement, as recommended by Praxis Medical Insights 3
AVF function may be successfully reestablished up to one week after thrombosis occurs, but early intervention maximizes success rates, according to Praxis Medical Insights 3
Thrombectomy of a fistula should be attempted as early as possible after thrombosis is detected, but can be successful even after several days, as stated by the American Journal of Kidney Diseases 5

The juxta-anastomotic region in AVFs represents a high-propensity site for stenosis formation, analogous to the vein-graft anastomosis in grafts, as reported by the Journal of the American College of Radiology 2
Stenotic lesions can occur at any point within the access system, including central veins and feeding arteries, and can provoke access dysfunction regardless of location, according to the Journal of the American College of Radiology 2