Martin R S, Edwards W H, Mulherin J L, Edwards W H, Jenkins J M, Hoff S J
Department of Surgery, Vanderbilt University Medical Center, Nashville, Tennessee.
Ann Surg. 1994 Jun;219(6):664-70; discussion 670-2. doi: 10.1097/00000658-199406000-00009.
Cryopreserved saphenous vein allografts have been offered as an alternative conduit for bypass in ischemic limbs. The authors examined the efficacy of this conduit for arterial bypass to the distal popliteal and tibial arteries in patients in whom autogenous vein was not available.
Previous experience with arterial and venous allografts has been unsatisfactory because of aneurysmal degeneration and poor patency. Endothelial loss and host rejection have been suggested as mechanisms of graft failure. Cryopreservation by modern techniques with rate controlled freezing, dimethyl sulfoxide (DMSO), and other cryopreservants, has addressed these issues and rekindled interest in vein allografts.
Over a period of more than 5 years, 115 cryopreserved vein allografts were implanted in 87 limbs to the distal popliteal (14) or tibial (101) arteries. The indication for surgery was rest pain in 56 procedures (49%), gangrene in 36 (31%), claudication in 21 (18%), and replacement of aneurysmal allografts in 2. Follow-up was 1 to 61 months (mean 25 months).
There was no significant difference in patency related to site of proximal or distal anastomosis, patency of runoff vessels, use of anticoagulation, age, sex, diabetes, hypertension, smoking, indication, source of graft, or use of multiple segments. Revision was required in six grafts for aneurysmal dilatation. Histologic examination of explanted sections of allografts showed no immune response, and immunosuppressive drugs were not used.
Although limb salvage has been satisfactory, long-term patency rates for cryopreserved vein allografts are poor when compared with autogenous vein. The cost of cryopreserved allografts far exceeds that of prosthetic grafts, for which comparable and superior results have been reported. Use of cryopreserved vein allografts should be reserved for situations in which adequate lengths of autogenous vein do not exist and the risk of infection of prosthetic grafts is high.
冷冻保存的大隐静脉同种异体移植物已被用作缺血肢体旁路移植的替代管道。作者研究了在无法获得自体静脉的患者中，这种管道用于腘动脉远端和胫动脉动脉旁路移植的疗效。
由于动脉瘤样变性和通畅率不佳，既往动脉和静脉同种异体移植物的应用效果并不理想。内皮细胞丢失和宿主排斥反应被认为是移植物失败的机制。采用速率控制冷冻、二甲基亚砜（DMSO）和其他冷冻保护剂的现代技术进行冷冻保存，解决了这些问题，并重新引发了人们对静脉同种异体移植物的兴趣。
在超过5年的时间里，将115个冷冻保存的静脉同种异体移植物植入87条肢体的腘动脉远端（14例）或胫动脉（101例）。手术指征为静息痛56例（49%）、坏疽36例（31%）、间歇性跛行21例（18%）以及2例置换动脉瘤样同种异体移植物。随访时间为1至61个月（平均25个月）。
与近端或远端吻合部位、流出道血管通畅情况、抗凝药物使用、年龄、性别、糖尿病、高血压、吸烟、手术指征、移植物来源或多节段使用情况无关，通畅率无显著差异。6个移植物因动脉瘤样扩张需要翻修。对同种异体移植物切除标本的组织学检查未显示免疫反应，且未使用免疫抑制药物。
尽管肢体挽救效果令人满意，但与自体静脉相比，冷冻保存的静脉同种异体移植物的长期通畅率较差。冷冻保存同种异体移植物的成本远远超过人工血管移植物，而人工血管移植物已报道有可比且更好的结果。冷冻保存的静脉同种异体移植物应仅用于不存在足够长度自体静脉且人工血管移植物感染风险高的情况。
