Wilbring Manuel, Tugtekin Sems Malte, Zatschler Birgit, Ebner Annette, Reichenspurner Hermann, Kappert Utz, Matschke Klaus, Deussen Andreas
Department for Cardiac Surgery, University Heart Center Dresden, Dresden, Germany.
Thorac Cardiovasc Surg. 2013 Dec;61(8):656-62. doi: 10.1055/s-0032-1311549. Epub 2012 Jul 12.
Saphenous vein grafts are still commonly used in cardiac, vessel and also in transplant surgery. In cardiac surgery, a desperate graft situation could force to keep nonutilized explanted vein segments after CABG in reserve for case of early graft failure. Historically there were no options for adequate long-time graft storage protecting the endothelial layer with its important antithrombotic and immunosuppressive functional aspects. Commonly isotonic saline solution (sodium chloride [NaCl]) has been used as a storing solution in this case. We investigated the impact of long-time storage in NaCl and a recently developed potassium-chloride and N-acetylhistidine enriched storage solution (TiProtec, Dr. Köhler Chemie, Germany) on endothelial function of saphenous veins.
Saphenous vein segments (n = 19) were intraoperatively isolated and stored for 24 and 96 hours. The segments were examined in a Mulvany-myograph to assess vessel function. Following preconstriction with norepinephrine, dose-response curves were assessed for relaxation with bradykinin and sodium-nitroprusside. We compared developed maximum wall tension and endothelial cell and smooth muscle cell (SMC) dependent vasodilatory function.
Maximum vessel wall tension was significantly better preserved in TiProtec-stored vessels after 24 h in comparison to segments stored in NaCl (5.11 ± 4.79 mN/mm vs. 2.48 ± 2.43 mN/mm; p = 0.033) and 96 h (4.94 ± 2.82 mN/mm vs. 2.80 ± 1.76 mN/mm; p = 0.042). Likewise endothelium-derived vasodilatory function was maintained significantly after 24 hours in TiProtec-stored vessels (36.9 ± 2.6% vs. 11.8 ± 30.9%; p = 0.005). After 96 hours, endothelium-dependent vascular function was nearly abolished in NaCl-stored vessels, but largely preserved in TiProtec-stored segments (20.6 ± 2.9% vs. 1.9 ± 4.3% in NaCl; p = 0.015). Sodium nitroprusside-mediated SMC-vasodilatory function was better maintained after 24 hours of storage in TiProtec group (88.8 ± 6.4% vs. 61.3 ± 8.2%; p = 0.009). After 96 hours of storage, SMC relaxation did not significantly differ between both storage groups which might be due to a distinct reduction of contractile function in NaCl-stored vessels (98.6 ± 5.0% and 77.9 ± 10.5% for Tiprotec and NaCl, respectively).
Vessel functions comprising contraction, endothelium-dependent and -independent vasodilatation are significantly reduced following 24 hours of cold storage in NaCl. After 96 hours of storage in NaCl these functions are nearly totally abolished. TiProtec is able to largely reduce this loss of function during cold storage. Therefore, TiProtec is a feasible option for longer term storage of saphenous vein grafts in CABG vessel and transplant surgery.
大隐静脉移植物仍常用于心脏、血管及移植手术。在心脏手术中，若移植情况危急，冠状动脉旁路移植术（CABG）后可能会保留未使用的切除静脉段以备早期移植失败时使用。历史上，对于长时间充分保存静脉移植物以保护具有重要抗血栓和免疫抑制功能的内皮细胞层，并无有效方法。通常情况下，等渗盐溶液（氯化钠[NaCl]）被用作这种情况下的保存溶液。我们研究了长时间保存在NaCl溶液以及最近研发的富含氯化钾和N - 乙酰组氨酸的保存溶液（TiProtec，德国科勒化学公司）中对大隐静脉内皮功能的影响。
术中分离出大隐静脉段（n = 19），并分别保存24小时和96小时。使用Mulvany肌动描记器检测这些静脉段的血管功能。先用去甲肾上腺素进行预收缩，然后评估缓激肽和硝普钠引起的舒张反应的剂量 - 反应曲线。我们比较了最大管壁张力以及内皮细胞和平滑肌细胞（SMC）依赖的血管舒张功能。
与保存在NaCl溶液中的静脉段相比，保存在TiProtec溶液中的静脉段在24小时后最大血管壁张力得到显著更好的保存（5.11±4.79 mN/mm对2.48±2.43 mN/mm；p = 0.033），在96小时后也是如此（4.94±2.82 mN/mm对2.80±1.76 mN/mm；p = 0.042）。同样，保存在TiProtec溶液中的静脉段在24小时后内皮依赖性血管舒张功能也得到显著维持（36.9±2.6%对11.8±30.9%；p = 0.005）。96小时后，保存在NaCl溶液中的静脉段内皮依赖性血管功能几乎完全丧失，但保存在TiProtec溶液中的静脉段大部分功能得以保留（20.6±2.9%对NaCl溶液中的1.9±4.3%；p = 0.015）。在TiProtec组中，保存24小时后硝普钠介导的SMC血管舒张功能得到更好的维持（88.8±6.4%对61.3±8.2%；p = 0.009）。保存96小时后，两组之间SMC舒张功能无显著差异，这可能是由于保存在NaCl溶液中的静脉段收缩功能明显降低所致（TiProtec组和NaCl溶液组分别为98.6±5.0%和77.9±10.5%）。
保存在NaCl溶液中24小时后，包括收缩、内皮依赖性和非依赖性血管舒张在内的血管功能显著降低。保存在NaCl溶液中96小时后，这些功能几乎完全丧失。TiProtec能够在很大程度上减少冷藏期间的这种功能丧失。因此，TiProtec是CABG血管和移植手术中长时间保存大隐静脉移植物的可行选择。
