Teshima Hideki, Hayashida Nobuhiko, Yano Hirohisa, Nishimi Masaru, Tayama Eiki, Fukunaga Shuji, Akashi Hidetoshi, Kawara Takemi, Aoyagi Shigeaki
Departments of Surgery and Pathology, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830-0011, Japan.
J Thorac Cardiovasc Surg. 2003 Aug;126(2):401-7. doi: 10.1016/s0022-5223(03)00702-5.
This study aims to reveal the morphological, histological, and immunohistochemical mechanism of pannus formation using resected pannus tissue from patients with prosthetic valve dysfunction.
Eleven patients with prosthetic valve (St Jude Medical valve) dysfunction in the aortic position who underwent reoperation were studied. We used specimens of resected pannus for histological staining (hematoxylin and eosin, Grocott's, azan, elastica van Gieson) and immunohistochemical staining (transforming growth factor-beta, transforming growth factor-beta receptor 1, alpha-smooth muscle actin, desmin, epithelial membrane antigen, CD34, factor VIII, CD68KP1, matrix metalloproteinase-1, matrix metalloproteinase-3, and matrix metalloproteinase-9).
Pannus without thrombus was observed at the periannulus of the left ventricular septal side; it extended into the pivot guard, interfering with the movement of the straight edge of the leaflet. The histological staining demonstrated that the specimens were mainly constituted with collagen and elastic fibrous tissue accompanied by endothelial cells, chronic inflammatory cells infiltration, and myofibroblasts. The immunohistochemical findings showed significant expression of transforming growth factor-beta, transforming growth factor-beta receptor 1, CD34, and factor VIII in the endothelial cells of the lumen layer; strong transforming growth factor-beta receptor 1, alpha-smooth muscle actin, desmin, and epithelial membrane antigen in the myofibroblasts of the media layer; and transforming growth factor-beta, transforming growth factor-beta receptor 1, and CD68KP1 in macrophages of the stump lesion.
Pannus appeared to originate in the neointima in the periannulus of the left ventricular septum. The structure of the pannus consisted of myofibroblasts and an extracellular matrix such as collagen fiber. The pannus formation after prosthetic valve replacement may be associated with a process of periannular tissue healing via the expression of transforming growth factor-beta.
本研究旨在利用人工瓣膜功能障碍患者切除的血管翳组织，揭示血管翳形成的形态学、组织学和免疫组化机制。
对11例接受再次手术的主动脉位人工瓣膜（圣犹达医疗瓣膜）功能障碍患者进行研究。我们将切除的血管翳标本用于组织学染色（苏木精和伊红染色、格罗科特染色、偶氮染色、弹性纤维染色）和免疫组化染色（转化生长因子-β、转化生长因子-β受体1、α-平滑肌肌动蛋白、结蛋白、上皮膜抗原、CD34、因子VIII、CD68KP1、基质金属蛋白酶-1、基质金属蛋白酶-3和基质金属蛋白酶-9）。
在左心室间隔侧瓣环周围观察到无血栓的血管翳；它延伸至枢轴护圈，干扰瓣叶直边的运动。组织学染色显示，标本主要由胶原和弹性纤维组织构成，伴有内皮细胞、慢性炎性细胞浸润和成肌纤维细胞。免疫组化结果显示，管腔层内皮细胞中转化生长因子-β、转化生长因子-β受体1、CD34和因子VIII表达显著；中层成肌纤维细胞中转化生长因子-β受体1、α-平滑肌肌动蛋白、结蛋白和上皮膜抗原表达强烈；残端病变巨噬细胞中转化生长因子-β、转化生长因子-β受体1和CD68KP1表达。
血管翳似乎起源于左心室间隔瓣环周围的新生内膜。血管翳的结构由成肌纤维细胞和细胞外基质如胶原纤维组成。人工瓣膜置换术后血管翳的形成可能与通过转化生长因子-β表达的瓣环周围组织愈合过程有关。
