Experimental model of arteriovenous fistula in pigs

To establish an experimental model of arteriovenous fistula in pigs. Ten fistulas were created in eight pigs, and angiography was performed 3 to 5 days after surgery. A follow-up angiogram of three fistulas was obtained 2 to 12 weeks later. In one animal, pathologic examination showed occlusion 8 weeks after a successful operations. Eight angiograms of nine fistulas in seven pigs were obtained; one animal died due to cardiac failure. In six pigs, high-flow fistulas were shown to be present, and in two, the fistulas were slow flow; a pseudoaneurysm was seen in one. A follow-up angiogram obtained in three cases showed occlusion of the fistula. Pathologic examination of one animal showed fibrosis in the occluded portion of the fistula. An arteriovenous fistula model was surgically established in 80% of cases; during follow-up, three fistulas were seen to be occluded due to fibrosis. This model can therefore be used within one week of surgery