Fundamental study on small-diameter vascular graft incorporated with new design concepts of mechanical compatibility and tissue morphogenesis.

结合机械相容性和组织形态发生新设计理念的小直径血管移植物的基础研究。

基本信息

批准号：
12470277
负责人：
MATSUDA Takehisa
金额：
$ 10.24万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12470277/
关键词：
co-axial artificial graft compliance vascular vessel

项目摘要

In order to minimize compliance mismatch between native artery and arterial graft prosthesis over the entire pressure regions, we proposed a coaxial double tubular artificial graft, which consists of an enhanced compliant inner tube and a less compliant outer tube, both of wihch were fabricated using well-controlled multiply micropored segmented polyurethane (SPU) films. Double tubular grafts were coaxially assembled by inserting the inner tube into the outer tube.Firstly, the pressure-diameter (P-D) relationship of canine common carotid arteries, which exhibited a "J" curve, was determined as a targeted artery. Two determinant variables, the pressure-induced distensibility of each tube and the intertubular space distance, were defined and formulated in several models of coaxial double tubular SPU grafts, which had various intertubular space distances, micropore densities and wall thicknesses. Tire distensibility of the inner tube determined the distensibility in the low-pressure regio … More ns, which was adjusted using wall thickness and microporosity. Thinner films with higher porosities resulted in a high pressure-induced distensibility. On the other hand, a low pressure-induced distensibility in the high-pressure regions was realized using an outer tube with a thicker wall and lower microporosity. The transition point from low- to high-pressure regions was determined by the intertubuiar distance using the theoretical values. On the basis of these results, we presented a prototype model of a coaxial double tubular graft that exhibited well-matched compliance with canine carotid artery.The graft was coaxially assembled by inserting the high-compliant inner tube (coated with photoreactive gelatin mixed with heparin) into the less-compliant outer tube (coated with photoreactive hydrophilic polymer). Twenty-eight coaxial double-tubular compliant grafts were implanted into the canine common carotid arteries up to 12 months in end-to end fashion. The overall patency rate was 85.7% (24 / 27). and neither rupture nor aneurysmal formation was observed. The neoarterial wall was reconslructed form the anastomoses into the luminal surface and into the imer-tubular space of the double-tubular graft, mainly with the myofibroblasts and inflammatory cells in the early stage and collagen-rich extracellular matrices in the late stage of implantation. Adhesion was prevented on the surface of the outer tube with the hydrophilic polymer coating. Although the "J" curve of the implanted prototype model was preserved at 1 month-implantation, the tissue ingrowth, the tissue-adhesion and the biodegradation of the SPU films were clarified to affect the mechanical property of the implanted coaxial double-tubular graft in the late stage. Less

为了最大限度地减少整个压力区域内天然动脉和动脉移植假体之间的顺应性不匹配，我们提出了一种同轴双管人工移植物，它由增强顺应性内管和顺应性较低的外管组成，两者均采用良好的制造方法通过将内管插入外管，将双管状移植物同轴组装。首先，压力-直径（P-D）关系。表现出“J”曲线的犬颈总动脉被确定为目标动脉，在同轴双管 SPU 的几种模型中定义和制定了两个决定性变量，即每根管的压力引起的扩张性和管间空间距离。具有不同管间空间距离、微孔密度和内胎壁厚的移植物决定了低压区域的扩张性，这是通过壁进行调整的。具有较高孔隙率的较薄薄膜导致较高的压力引起的膨胀性，而使用具有较厚的壁和较低的微孔性的外管实现了高压区域的较低的压力引起的膨胀性。从低压区域到高压区域的过渡点是通过使用理论值的管间距离来确定的。基于这些结果，我们提出了同轴双管移植物的原型模型，该模型具有良好的顺应性。犬颈动脉。通过将高顺应性内管（涂有与肝素混合的光反应性明胶）插入低顺应性外管（涂有光反应性亲水聚合物）中，同轴组装移植物。二十八个同轴双管顺应性移植物。以端到端方式植入犬颈总动脉长达 12 个月，总体通畅率为 85.7%（24 / 27）并且没有观察到新动脉壁从吻合处重建到管腔表面和双管移植物的内管间隙，早期主要是肌成纤维细胞和炎症细胞。富含胶原蛋白的细胞外基质在植入后期被亲水性聚合物涂层阻止粘附在外管表面。植入原型模型在植入1个月时保留了“J”曲线，明确了SPU膜的组织长入、组织粘附和生物降解对植入同轴双管移植物后期力学性能的影响。少阶段。