Abstract: 【Abstract】Objective To observe the effect of extravascular stent coated with α-cyanoacrylate (α-CA) on venous intimal hyperplasia in juxta-anastomotic veins of arteriovenous fistula (AVF) in rabbits. Method Twenty adult male rabbits were randomly divided into control group (n=10) and α-CA group (n=10). AVF was created by end- to- end anastomosis of common carotid artery and common jugular vein in animals of both groups. In the α-CA group, extravascular stent coated with α-CA was applied to the outer surface of juxtaanastomotic vein. Color Doppler ultrasonography was used to examine the diameter and peak systolic flow velocity of the juxta-anastomotic vein immediately after the operation and after the operation for one month. The juxta- anastomotic vein was taken after the operation for one month, the intimal thickness and the ratio of intima/ media thickness were measured after hematoxylin-eosin (HE) staining, and the expression of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA) were detected by immunohistochemistry. Result After the operation for one month, color Doppler ultrasonography showed that the diameter of juxtaanastomotic vein of AVF was 3.50±0.30 mm in the control group higher than the diameter of 3.22±0.23 mm in the α-CA group (t=2.326, P=0.032); the peak systolic flow velocity in juxta- anastomotic vein of AVF was 512.0±83.6mm/s in the control group, lower than the velocity of 668.6±64.1mm/s in the α-CA group (t=4,701,P＜0.001). H-E staining of the intimal in the juxta-anastomotic vein showed that the intimal thickness was 35.3±6.1μm in the control group, higher than that of 24.8±5.6μm in the α-CA group(t=3.987, P=0.001). Immu-nohistochemistry of the intimal in the juxta- anastomotic vein showed that the positive expression rates of PCNA and α-SMA in the in intimal cells were 20.5±3.9% and 25.9± 4.7% respectively in the control group, higher than those of 14.2±3.1% and 16.5±3.7% respectively in the α-CA group (t=3.993 and 4.948 respectively, P=0.001 and <0.001 respectively). Conclusion Extravascular stent coated with α-cyanoacrylate can prevent
juxta-anastomotic vein of the AVF from intimal hyperplasia in rabbits.

Key words: Arteriovenous fistula, Intimal hyperplasia, α-cyanoacrylate, Extravascular stent