Cryoplasty for the treatment of iliac artery stenosis in canine model

Abstract

Objective To evaluate the treatment effect of balloon angioplasty and cryoplasty on iliac artery stenosis in canine model. Methods Canine models of iliac artery stenosis were established with surgical ligation and transfixion.Models were randomly divided into two groups:iliac artery stenosis treated by cryoplasty (n=8) and by balloon angioplasty (n=8).The degree of iliac artery stenosis of two model groups was assessed by digital subtraction angiography (DSA) immediately and two weeks after the angioplasties.Then all the dogs were executed for pathological observation of the target vessels. Results Sixteen canine models of iliac artery stenosis were established by surgical ligation and transfixion method with 100% success rate.DSA showed there was (45±12) % of residual artery stenosis in the cryoplasty group immediately after surgery,while it was (39±12) % in the balloon angioplasty group,and there was no significant difference between them (t=3.183,P>0.05).The artery stenosis of cryoplasty group was (48±17) % after two weeks and not significantly different from that after surgery immediately (t=-1.271,P>0.05).The artery stenosis of balloon angioplasty group was (67±13) % after two weeks,and it was significantly higher compared with at after surgery immediately (t=-6.666,P<0.01).The degree of vascular stenosis in balloon angioplasty group was severer than that in cryoplasty group two weeks after angiography (P=0.041).The pathological examination showed artery intimal hyperplasia in cryoplasty group was milder than that in balloon angioplasty group and neointimal content of collagen in cryoplasty group was less than that in balloon angioplasty group. Conclusions The animal models of iliac artery stenosis were established successfully with surgical ligation and transfixion by damaging the intima and media of arterial wall.Compared with balloon angioplasty,the cryoplasty was able to inhibit proliferation of intimal and reduce collagen synthesis to prevent the iliac artery restenosis. Key words: Models,animal; Dogs; Angioplasty,balloon; Cryotherapy; Iliac artery stenosis