射频球囊血管成形术对兔动脉粥样硬化腹主动脉形态学的影响

发布时间：2018-03-19 19:28

本文选题：射频球囊血管成形术　切入点：动脉重构　出处：《天津医科大学》2017年硕士论文　论文类型：学位论文

【摘要】：目的:我们设计研发了一种新型的温控式血管内射频消融球囊,采用纵向线形式消融增生的动脉内膜,探究射频球囊血管成形术对动脉粥样硬化斑块影响、对动脉的重构作用及可能的机制,为治疗动脉粥样硬化提供一种新的方法。方法:通过高脂喂养联合球囊损伤动脉内膜方法建立兔腹主动脉动脉粥样硬化模型,于第12周末随机处死两只行病理组织学检查,确认动脉粥样硬化模型建立成功。然后分别应用射频球囊及普通球囊对家兔腹主动脉行血管成形术,术后喂养正常饲料,并于术后1小时、7天、14天、28天四个时间点处死动物,取相应腹主动脉标本行病理组织学及免疫组织化学检查;比较7天、14天、28天两组管腔横截面积、内膜面积、中膜面积、内膜面积与中膜面积比值、管腔横截面积与血管外壁面积比值等管腔形态学指标及管壁TGF-β1、MMP-2、MMP-9蛋白的表达是否有差异及随时间变化情况,探讨射频球囊血管成形术对粥样硬化动脉组织形态学的影响及可能的机制。结果:(1)球囊损伤动脉内膜联合高脂饲料喂养12周末,可见整个腹主动脉外观呈灰白色,病理检查,可见动脉内膜明显增生,表面有纤维组织覆盖,构成纤维帽,纤维帽下可见大量炎性细胞及泡沫细胞,中膜可见弹力纤维崩解、断裂,平滑肌细胞排列紊乱,确认兔腹主动脉动脉粥样硬化模型建立成功。(2)射频球囊扩张组与普通球囊扩张组相比,能显著增加管腔内径,减少内膜及中膜面积,管壁变薄,对管腔重构作用明显,并且射频功率越大,对管腔的扩张作用越显著。(3)7天、14天、28天,射频球囊扩张组可见射频消融部位出现局部纤维化,内膜炎性细胞及泡沫细胞减少,甚至消失,中膜平滑肌细胞坏死,弹力纤维变性、拉伸变直。(4)功率较大时,管壁出现全层透壁坏死,发生管腔全层纤维化,内膜可见炎性细胞浸润。(5)1小时,两组TGF-β1、MMP-2、MMP-9蛋白表达未见明显差异;7天、14天、28天,消融扩张部位表达明显增加,内膜全层高表达TGF-β1、MMP-2、MMP-9蛋白。结论:1.射频球囊血管成形术可显著增加管腔面积,可能与减少内膜及中膜面积,使管壁变薄有关。2.射频消融部位出现纤维化,内膜炎性细胞及泡沫细胞减少、消失,中膜平滑肌细胞坏死,弹力纤维变性、拉伸,增加斑块稳定性。3.射频热损伤可使消融部位TGF-β1、MMP-2、MMP-9表达增加。4.射频能量较高时,使整个管腔出现透壁全层坏死,胶原纤维增生,管壁弹性消失,中期可见内膜出现炎性细胞浸润。
[Abstract]:Objective: to investigate the effect of radiofrequency balloon ablation (RFCA) on atherosclerotic plaques. The effect of arterial remodeling and its possible mechanism provide a new method for the treatment of atherosclerosis. Methods: a rabbit model of abdominal aortic atherosclerosis was established by high-fat feeding combined with balloon injury of artery intima. At the end of the 12th week, two rabbits were randomly killed for histopathological examination, which confirmed that the atherosclerosis model was established successfully, and then the rabbit abdominal aorta was treated with radiofrequency balloon and ordinary balloon respectively, and fed with normal diet after operation. The animals were killed at 4 time points, 1 hour and 14 days after operation, and the corresponding abdominal aorta specimens were taken for histopathological and immunohistochemical examination, and the cross sectional area of lumen, intimal area and middle membrane area were compared between the two groups on day 7 and day 14 and day 28, respectively. The ratio of intimal area to middle membrane area, the ratio of lumen cross-sectional area to vascular outer wall area, and the expression of TGF- 尾 _ 1MMP _ 2 / MMP-9 protein were different and varied with time. To investigate the effect of radiofrequency balloon angioplasty on the histomorphology of atherosclerotic artery and its possible mechanism. Results the whole abdominal aorta was grayish white at 12 weeks after balloon injury and fed with high fat diet. The intima of the artery obviously proliferated, the surface was covered with fibrous tissue, forming a fibrous cap, a large number of inflammatory cells and foam cells could be seen under the fibrous cap, and elastic fibers could be disintegrated, broken down, and smooth muscle cells arranged in disorder under the fibrous cap. It was confirmed that compared with the normal balloon dilatation group, the radiofrequency balloon dilatation group could significantly increase the diameter of the lumen, decrease the area of the intima and the middle membrane, and thin the wall of the rabbit abdominal aorta. The radiofrequency balloon dilatation group had a significant effect on the remodeling of the lumen. Moreover, the larger the RF power, the more significant the dilatation of the lumen was. In the radiofrequency balloon dilatation group, the local fibrosis appeared in the radiofrequency ablation site, and the inflammatory cells and foam cells in the endometrium decreased or even disappeared in the radiofrequency balloon dilatation group. When the power of medial smooth muscle cell necrosis, elastic fiber degeneration and stretch straightening is high, there is necrosis of the whole layer through the wall, fibrosis in the whole layer of the lumen, and inflammatory cell infiltration in the intima for 1 hour. There was no significant difference between the two groups in the expression of TGF- 尾 1, MMP-2 and MMP-9. The expression of TGF- 尾 1, MMP-2, MMP-9 and MMP-9 in the whole intima was significantly increased after 14 days and 28 days. Conclusion: 1. Radiofrequency balloon angioplasty can significantly increase the lumen area. It may be related to reducing the area of intima and media and thinning the wall of the tube. 2. Fibrosis occurs in the site of radiofrequency ablation, the inflammatory cells and foam cells of the intima decrease and disappear, the smooth muscle cells of the media are necrosed, the elastic fibers denaturation and stretch, Increase plaque stability .3. radiofrequency thermal injury can increase the expression of TGF- 尾 _ 1MMP _ 2 and MMP-9 in ablation site .4.When radiofrequency energy is high, the whole lumen will be necrosed, collagen fiber will proliferate, wall elasticity will disappear, and inflammatory cell infiltration can be seen in the middle stage.
【学位授予单位】：天津医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R543.5

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