1/6. Angiogenesis, vascular endothelial growth factor and platelet-derived growth factor-BB expression, iron deposition, and oxidation-specific epitopes in stented human coronary arteries.Pathogenesis of in-stent restenosis remains poorly understood because information from human histopathologic studies is scarce. We used an improved saw-grinding and cutting method on methacrylate-embedded samples containing metal stents, which allows in situ hybridization and immunohistochemical analysis of in-stent restenosis. Twenty-one samples were collected 3 hours to 3 years after stenting from 6 patients aged 36 to 81 years. Except in very early samples collected within hours after the stent deployment, neovascularization was present in all segments studied. At advanced stages, extensive neovascularization was located mainly at the luminal side of the stent struts and was only rarely accompanied by inflammatory cells. The neovessels colocalized with vascular endothelial growth factor (VEGF)-A mRNA and protein expression as well as with iron deposits and oxidation-specific epitopes, which imply the presence of chronic oxidative stress. VEGF-A expression was detected in the same areas containing macrophages, endothelial cells, and, to a lesser extent, smooth muscle cells, which also showed platelet-derived growth factor-BB expression. We conclude that in-stent restenosis features neovascularization, VEGF-A and platelet-derived growth factor-BB expression, and iron deposition, which is most probably derived from microhemorrhages. These mechanisms may play an important role in the development of neointimal thickening and could provide useful targets for the prevention and treatment of in-stent restenosis.- - - - - - - - - - ranking = 1keywords = neointima (Clic here for more details about this article) |
2/6. No delayed restenosis at 18 months after implantation of sirolimus-eluting stent.sirolimus-eluting stent is emerging as a potential solution for the prevention of restenosis. Recently, a sustained suppression of neointimal proliferation 12 months after implantation of this stent was reported. This is the first report of angiographic and IVUS images 18 months after the implantation of a sirolimus-eluting stent.- - - - - - - - - - ranking = 1keywords = neointima (Clic here for more details about this article) |
3/6. Acute myocardial infarction caused by thrombotic occlusion at a stent site two years after conventional stent implantation.Two cases of acute myocardial infarction caused by thrombotic occlusion at the conventional stented site two years after stenting are described. Late thrombotic stent occlusion may be caused by atherosclerotic regression, sustained inflammatory reaction, and inhibition of proliferation of neointima. Cardiologists must be aware of the potential for late thrombosis following even conventional stent implantation.- - - - - - - - - - ranking = 1keywords = neointima (Clic here for more details about this article) |
4/6. Human coronary morphology after beta radiation brachytherapy of in-stent restenosis.This case report discusses the human coronary morphological findings 18 hours after brachytherapy (beta radiation) of an in-stent restenosis. brachytherapy produced aseptic inflammation of the periadventitial connective tissue integrating the vasa vasorum in the acute phase. The stent neointima eight months after stenting and acutely 18 hours after radiation consisted of the same cellular components as human stent neointima of specimen not additionally treated with radiation. No evidence of necrosis or excessive fibrotic alterations of the arterial vessel wall have been found.- - - - - - - - - - ranking = 2keywords = neointima (Clic here for more details about this article) |
5/6. Severe stenosis of anastomoses by using the symmetry aortic connector system.The St. Jude Medical Symmetry Aortic Connector System was developed to create the proximal vein graft anastomoses in coronary artery bypass grafting. We describe three symptomatic patients with severe stenosis of the proximal anastomosis several months after using the Symmetry aortic connector system. Intravascular ultrasound study showed anastomotic neointimal hyperplasia.- - - - - - - - - - ranking = 1keywords = neointima (Clic here for more details about this article) |
6/6. Comparative endoluminal visualization of taxus crush-stenting at 9 months follow-up by intravascular ultrasound and optical coherence tomography.We report a case of crush-stenting with paclitaxel-eluting taxus stents in a left anterior descending artery (LAD) bifurcation lesion. In order to obtain precise information on the mid-term neointimal response of the main vessel to this approach, we evaluated the patient angiographically 9 months later, including intravascular visualization with optical coherence tomography (OCT), a new high resolution imaging technique, and IVUS. The evaluation revealed that there was a homogeneous neointimal coverage of the main vessel stents without evidence of significant recurrent lumen renarrowing or malappositions. Compared to IVUS, OCT proved the coverage of the stent struts adjacent to the vessel wall with a superior imaging quality and, in addition, provided new insights into the stent performance at the open bifurcation site.- - - - - - - - - - ranking = 2keywords = neointima (Clic here for more details about this article) |