Department of Cardiovascular Surgery, Semmelweis University, Budapest, Hungary.
Eur J Vasc Endovasc Surg. 2010 Jul;40(1):88-93. doi: 10.1016/j.ejvs.2010.01.008. Epub 2010 Feb 19.
Improved maintenance of endothelial function and higher viability of saphenous vein grafts stored in a complex tissue culture medium (TCM) have been demonstrated. This article studies the biomechanical properties of saphenous vein segments.
Biomechanical properties of 72 saphenous vein segments remaining from coronary bypass grafting of 32 patients have been studied after different storage procedures.
The materials studied included fresh segments, segments stored in a cooled conventional physiological salt solution (normal Krebs-Ringer (nKR)) for 1-2 weeks, segments stored in a cooled chemically defined TCM (X-Vivo) for 1,2,3 and 4 weeks and segments cryopreserved for a few weeks.
Specimens were cannulated at both ends and pressure-diameter curves were recorded in the 0-85-mmHg range in nKR with 10 microM norepinephrine added to induce maximum smooth muscle contraction, as well as in Ca(2+)-free medium to induce full relaxation. Tensile strength was checked at 300 mmHg. Distensibility, elastic modulus and active strain were computed.
Segments stored in nKR dilated morphologically, their distensibility decreased and they lost their ability to contract (1.5+/-0.7% from 10.1+/-1.5% of control) in 1 week. The TCM-stored segments preserved their contractility until 1 week, and this parameter only slowly decreased afterwards (first week, 11.5+/-7.3%; fourth week, 3.9+/-0.6%). There was a slight decrease in wall thickness but the lumen diameter was not affected. The elastic parameters of these segments were practically identical to those of fresh segments. Cryopreserved segments narrowed morphologically, their wall thickened and contractility diminished.
Storage in TCM helps preserve the passive and active biomechanical properties of human saphenous vein segments. Such properties can be expected to improve graft tissue viability.
已证明，在复杂的组织培养基（TCM）中保存的内皮功能得到改善，并且大隐静脉移植物的存活率更高。本文研究了大隐静脉段的生物力学特性。
对 32 名患者冠状动脉旁路移植术剩余的 72 个大隐静脉段进行了不同保存程序后的生物力学特性研究。
研究材料包括新鲜的静脉段、在冷藏的常规生理盐水溶液（正常 Krebs-Ringer（nKR））中保存 1-2 周的静脉段、在冷藏的化学定义的 TCM（X-Vivo）中保存 1、2、3 和 4 周的静脉段以及冷冻保存数周的静脉段。
在 nKR 中，静脉段的两端均进行了套管，并记录了 0-85mmHg 范围内的压力-直径曲线，同时加入 10μM 去甲肾上腺素以诱导最大的平滑肌收缩，以及在不含 Ca2+的介质中以诱导完全松弛。在 300mmHg 下检查拉伸强度。计算可扩展性、弹性模量和主动应变。
在 nKR 中保存的静脉段在形态上扩张，其可扩展性降低，并且在 1 周内失去了收缩能力（从 10.1%+/-1.5%的对照值下降到 1.5%+/-0.7%）。TCM 保存的静脉段保持收缩能力直到 1 周，此后该参数缓慢下降（第一周，11.5%+/-7.3%；第四周，3.9%+/-0.6%）。静脉段的壁厚度略有下降，但管腔直径不受影响。这些静脉段的弹性参数与新鲜静脉段基本相同。冷冻保存的静脉段在形态上变窄，壁变厚，收缩力减弱。
在 TCM 中保存有助于保持人源性大隐静脉段的被动和主动生物力学特性。这种特性有望提高移植物组织的存活率。
