Department of Pediatric Cardiology and Pediatric Intensive Care Medicine, Georg-August University Goettingen, Robert Koch Strasse 40, Goettingen, Germany.
Circ Cardiovasc Interv. 2009 Apr;2(2):90-6. doi: 10.1161/CIRCINTERVENTIONS.108.810507. Epub 2009 Feb 20.
We sought to evaluate tissue reactions within and at the surface of devices for interventional therapy of septal defects and to identify antigen characteristics of neotissues.
Atrial or ventricular septal defect-occlusion devices (Amplatzer, n=7; Cardioseal/Starflex, n=3) were processed using a uniform protocol after surgical removal from humans (implantation time, 5 days to 4 years). Devices were fixed in formalin and embedded in methylmethacrylate. Serial sections were obtained by sectioning with a diamond cutter and grinding, thus saving the metal/tissue interface for histologic evaluation. Immunohistochemical staining was performed using conventional protocols. Superficial endothelial cells stained positive for von Willebrand factor. Within the newly formed tissues, fibroblast-like cells were identified with a time-dependent expression of smooth muscle cell maturation markers (smooth muscle actin, smooth muscle myosin, h-caldesmon, and desmin) beside extracellular matrix components. Neovascularization of the newly formed tissues was demonstrated with the typical immunohistochemical pattern of capillaries and small vessels. Inflammatory cells could be identified as macrophages (CD68+) and both T-type and B-type lymphocytes (CD3+, CD79+).
This is the first presentation of results from serial immunohistochemical staining of a collection of explanted human septal-occlusion devices. A time-dependent maturation pattern of the fibroblast-like cells in the neotissues around the implants could be described. Neoendothelialization was seen in all specimens with implantation times of 10 weeks or more. The time course of neoendothelialization, as seen in our study, further supports the clinical practice of anticoagulant or antiplatelet therapy for 6 months after implantation. This time interval should be sufficient to prevent thromboembolic events due to thrombus formation at the foreign surface of cardiovascular implants.
我们旨在评估介入治疗室间隔缺损器械的内部和表面的组织反应,并确定新组织的抗原特性。
在从人体取出后(植入时间为 5 天至 4 年),采用统一的方案处理房间隔或室间隔缺损封堵器械(Amplatzer,n=7;Cardioseal/Starflex,n=3)。器械用甲醛固定并包埋在甲基丙烯酸甲酯中。通过金刚石切割和研磨获得连续切片,从而为组织学评估保留金属/组织界面。采用常规方案进行免疫组织化学染色。表面内皮细胞对血管性血友病因子呈阳性染色。在新形成的组织中,鉴定出成纤维细胞样细胞,这些细胞随着时间的推移表达平滑肌细胞成熟标志物(平滑肌肌动蛋白、平滑肌肌球蛋白、h-钙调蛋白和结蛋白)和细胞外基质成分。新形成的组织中的新生血管化通过典型的毛细血管和小血管免疫组织化学模式得以证明。炎症细胞可被鉴定为巨噬细胞(CD68+)和 T 型和 B 型淋巴细胞(CD3+、CD79+)。
这是首次展示一系列植入人体室间隔封堵装置的连续免疫组织化学染色结果。在植入物周围的新组织中,成纤维细胞样细胞的时间依赖性成熟模式可以被描述。在植入时间为 10 周或更长时间的所有标本中均可见新的内皮化。在我们的研究中观察到的新内皮化时间过程进一步支持了植入后抗凝或抗血小板治疗 6 个月的临床实践。这个时间间隔应该足以防止由于心血管植入物外表面形成血栓而导致的血栓栓塞事件。