Eskew T D, Ollerenshaw J D, Philpott J M, Dennis K, Dawson P, Sun Y S, Chitwood W R, Lust R M
Cardiovascular Center, East Carolina University School of Medicine, Greenville, North Carolina 27858-4354, USA.
ASAIO J. 1997 Sep-Oct;43(5):M522-6.
Intimal hyperplasia (IH) limits the long-term success of veins as arterial grafts. IH occurs in veins partly as an adaptive process to arterial pressure conditions. The authors have previously reported early success with cryopreserved (CP) saphenous veins as aortocoronary bypass grafts, and they have hypothesized that CP arterial segments were already structurally adapted for arterial conditions. Six femoral arterial segments were harvested from three adult donor dogs, and cryopreserved. The segments were thawed and implanted into six recipient dogs, in end-to-end fashion, as interpositional grafts in the femoral artery. A similar length of native femoral artery was removed from the implant site and grafted in the contralateral femoral artery of the same animal to serve as native autograft-matched controls. Grafts were harvested bilaterally after 2 (n = 3) and 4 weeks (n = 3), perfusion fixed (80 mmHg, 15 min), and analyzed histologically. All grafts were patent at harvest, and flows distal to the grafted segments were not significantly different between grafts within an animal either at implant or subsequent harvest. Although CP arterial grafts still showed slight but significant dilation compared with native autograft, the dilation was much less than seen previously with either CP or native venous segments. No evidence of inflammation or IH was seen in CP arterial grafts. The absence of early IH or inflammation suggests that CP small diameter arteries may perform better than many currently available allograft tissues and synthetic prosthetics.
内膜增生（IH）限制了静脉作为动脉移植物的长期成功率。内膜增生在静脉中部分是作为对动脉压力条件的一种适应性过程而发生的。作者此前曾报道，冷冻保存（CP）的大隐静脉作为主动脉冠状动脉搭桥移植物取得了早期成功，并且他们推测CP动脉段在结构上已经适应了动脉条件。从三只成年供体犬身上采集了六段股动脉，并进行了冷冻保存。将这些动脉段解冻后，以端对端的方式植入六只受体犬体内，作为股动脉的间置移植物。从植入部位切除相似长度的自体股动脉，并将其移植到同一只动物的对侧股动脉中，作为自体移植匹配对照。在术后2周（n = 3）和4周（n = 3）时双侧采集移植物，进行灌注固定（80 mmHg，15分钟），并进行组织学分析。所有移植物在采集时均通畅，并且在植入时或随后采集时，同一动物体内移植物段远端的血流在各移植物之间无显著差异。尽管与自体移植相比，CP动脉移植物仍显示出轻微但显著的扩张，但这种扩张远小于先前CP或自体静脉段的情况。在CP动脉移植物中未发现炎症或内膜增生的证据。早期内膜增生或炎症的缺失表明，CP小直径动脉可能比许多目前可用的同种异体移植组织和人工合成假体表现更好。
