Arteriovenous fistula in the rat tail: a new model of hemodialysis access dysfunction.

Problems with vascular access are an important cause of morbidity and mortality in hemodialysis patients. We established a rodent model of arteriovenous fistula by anastomosing the end of a lateral vein to the side of the ventral artery of the rat tail. All operations were technically successful and in all animals the fistula was patent with a dilated fistula vein clearly visible after 28 days. Neointimal hyperplasia was found in 4 out of 5 fistulae with varied pathology from immature to more mature lesions seen both proximal and distal to the anastomosis. There was no particular pattern to the presence of or type of lesion found at any particular site of the fistulae. This fistula promises to be useful in analyzing pathologic processes that occur in native arteriovenous fistulae since the vein is accessible to functional studies and to test new subcutaneous or intravascular treatments.