Yu T J, Ho D M, Chu C C
Department of Surgery, Veterans General Hospitals-Taipei, Taiwan, Republic of China.
J Invest Surg. 1994 May-Jun;7(3):195-211. doi: 10.3109/08941939409018286.
The objectives of this research were (1) to determine whether the use of partially absorbable vascular grafts would improve their nonthrombogenic performance and whether they are more prone to aneurysmal dilation and subsequent failure in vivo, and (2) to find out the relationships, if any, between these in vivo and the previously reported in vitro data with an emphasis on how the in vitro changes in fabric structure and properties related to these in vivo data. Bicomponent vascular fabrics were made from Dacron and polyglycolic acid (PGA) yarns with a range of composition ratios of the PGA to Dacron. Both woven and single Jersey knit fabrics were made, and implanted in dogs for 4 months. The following findings and relationships were obtained. (1) The bicomponent vascular fabrics resulted in a full-wall healing in the thoracic aorta of dogs. All bicomponent vascular grafts in survived dogs exhibited 100% patency, no thrombus or aneurysmal formation, no hematoma or seroma around the grafts, and no fibrin coagula in the inner capsules. The gross morphology of the regenerated tissues was very similar visually to the adjacent original arterial tissue. Histologically, the luminal surface was lined with a layer of endothelial cells with myofibroblasts, fibroblasts, and collagens underneath. (2) The extent of the full-wall healing depended on the type of fabric structure, the concentration of absorbable yarns, the location of absorbable yarns (for the woven group only), and initial water permeability. It is believed that the concentration effect was related to the level of macrophage activation from the degradation products of the absorbable yarns, while the location effect was attributed to the various types of fabric structure change on the degradation of the absorbable yarns. (3) In general, the knitted group (K), was better than the woven group (W). K3 showed the best in vivo performance in the knitted group. (4) In the woven group, W3 was the best. The incorporation of absorbable yarns in the weft direction of the bicomponent fabrics (W3) resulted in a velourlike, loose and porous fabric surface for facilitating tissue ingrowth. The placement of absorbable yarns in the warp direction (W1), however, did not show this unique surface morphology. Calcification was, however, occasionally observed in the woven samples with low initial water permeability. These observed in vivo performances correlated well with our previously reported in vitro study.
（1）确定使用部分可吸收血管移植物是否会改善其抗血栓形成性能，以及它们在体内是否更容易发生动脉瘤样扩张和随后的失效；（2）找出这些体内情况与先前报道的体外数据之间的关系（如有），重点是织物结构和性能的体外变化如何与这些体内数据相关。双组分血管织物由涤纶和聚乙醇酸（PGA）纱线制成，PGA与涤纶的组成比例范围不同。制备了机织和单面针织织物，并将其植入犬体内4个月。得到了以下发现和关系。（1）双组分血管织物使犬胸主动脉实现全壁愈合。存活犬体内的所有双组分血管移植物均表现出100%的通畅率，无血栓或动脉瘤形成，移植物周围无血肿或血清肿，内囊无纤维蛋白凝块。再生组织的大体形态在视觉上与相邻的原始动脉组织非常相似。组织学上，管腔表面衬有一层内皮细胞，其下方有肌成纤维细胞、成纤维细胞和胶原蛋白。（2）全壁愈合的程度取决于织物结构类型、可吸收纱线的浓度、可吸收纱线的位置（仅针对机织组）以及初始透水性。据信，浓度效应与可吸收纱线降解产物激活巨噬细胞的程度有关，而位置效应则归因于可吸收纱线降解时织物结构的各种变化。（3）一般来说，针织组（K）优于机织组（W）。K3在针织组中表现出最佳的体内性能。（4）在机织组中，W3是最好的。在双组分织物的纬向加入可吸收纱线（W3）导致织物表面呈天鹅绒状、疏松且多孔，便于组织向内生长。然而，在经向放置可吸收纱线（W1）并未呈现这种独特的表面形态。不过，在初始透水性较低的机织样品中偶尔会观察到钙化现象。这些观察到的体内性能与我们先前报道的体外研究结果相关性良好。
