Yang Qi, Lei Dong, Huang Shixing, Yang Yi, Yang Yang, Ye Xiaofeng, You Zhengwei, Zhao Qiang
Department of Cardiac Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-dimension Materials (Donghua University), College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
Ann Transl Med. 2020 Feb;8(4):102. doi: 10.21037/atm.2020.01.16.
The poor long-term patency ratio of vein grafts prevents patients from benefiting from coronary artery bypass graft (CABG). It is reported that external venous stents have notably improved the patency ratio of stented vein grafts in animal models. The most crucial influence on stented grafts' fate is the size of the stents. This study aims to investigate the effects on intimal hyperplasia and inflammation of vein graft by using different sizes of stents and explore the potential mechanism.
Two different sizes of external stents were fabricated through 3D printing technology. Male SD rats were divided into three groups. In the control group rat's autologous left jugular vein was grafted on the ipsilateral artery directly. In the stent groups, grafts were surrounded by two different-sized stents before anastomosing with arteries. The patency ratio and diameter of the grafts were examined by ultrasound. Masson staining was used to characterize intimal hyperplasia. The expression of inflammatory factors was detected by immunohistochemical staining. Moreover, TUNEL staining was used to label apoptotic cells.
The two sizes of external stents were fabricated by 3D printing technology. In the control group, the intima area and wall thickness dramatically increased 8 weeks after implantation. While in the stent groups, these data only slightly increased, especially in the 1.5 mm-stent group. The expressions of inflammatory factors in TNF signaling were more remarkable than in the control group. On the contrary, the expressions were rarely detected in the stent groups. Similarly, the number of TUNEL positive cells dramatically decreased by using the appropriate-sized stent.
In this study, we concluded that the appropriate sizes of external stents could effectively inhibit vein graft neointima formation, attenuate inflammatory reaction and reduce cell apoptosis, which might improve the long-term patency ratio of vein grafts.
静脉移植物长期通畅率较低，这使得患者无法从冠状动脉旁路移植术（CABG）中获益。据报道，在动物模型中，外部静脉支架显著提高了带支架静脉移植物的通畅率。对带支架移植物命运的最关键影响因素是支架的尺寸。本研究旨在探讨使用不同尺寸的支架对静脉移植物内膜增生和炎症的影响，并探索其潜在机制。
通过3D打印技术制作两种不同尺寸的外部支架。将雄性SD大鼠分为三组。对照组将大鼠自体左颈静脉直接移植到同侧动脉上。在支架组中，移植物在与动脉吻合前被两种不同尺寸的支架环绕。通过超声检查移植物的通畅率和直径。采用Masson染色来表征内膜增生。通过免疫组织化学染色检测炎症因子的表达。此外，使用TUNEL染色标记凋亡细胞。
通过3D打印技术制作了两种尺寸的外部支架。在对照组中，植入8周后内膜面积和管壁厚度显著增加。而在支架组中，这些数据仅略有增加，尤其是在1.5毫米支架组。TNF信号通路中炎症因子的表达在支架组中比对照组更显著。相反，在对照组中很少检测到这些表达。同样，使用合适尺寸的支架可使TUNEL阳性细胞数量显著减少。
在本研究中，我们得出结论，合适尺寸的外部支架可有效抑制静脉移植物新生内膜形成，减轻炎症反应并减少细胞凋亡，这可能会提高静脉移植物的长期通畅率。
