聚对二氧环己酮缝线编织构建仿生型人工小口径血管支架的实验研究

目的 探讨以聚对二氧环己酮(polydioxanone,PDS)缝线编织网管为中间弹力层,构建仿生型三层小口径血管支架的可行性,并检测其生物力学性能.方法 采用7-0 PDS缝线编织内径为4mm的网管,比较不同的编织结构和编织工艺角对PDS网管生物力学性能的影响.将小肠黏膜下基质包被于PDS支架外表面,以8-0 PDS缝线沿纵轴连续缝合固定,支架内层覆以复合硫酸软骨素共混胶原,真空冷冻干燥.检测血管支架的生物力学性能(爆破压力、抗拉伸能力、顺应性等),并与犬颈总动脉进行比较.方果 选择65°的编织工艺角编织内径为4 mm规则结构的网管,长度为3～5 cm;所制备的人工血管的爆破压为(43,50±8.30)kPa,断裂强度为(19.10±1.56)N,应变率为(42.88±3.16)%,径向顺应性为(5.96±0.87)%/100 mm Hg.方论 以PDS编织网管作为中间弹力层构建的复合型人工小血管支架力学性能满意,可以满足动物体内移植试验的需要.

Suture-reinforced polydioxanone-elastin for tissue engineering of small-diameter vessels: a feasibility study

Objective To investigate the feasibility of constructing sutuze-reinforced polydioxanone(PDS)multilayer small-caliber artificial scaffolds and determine its biomechanical properties.Methods 7-0PDS fibers were woven into a stent with 4 mm inner diameter.The influence of different weaving angle and knitting structure on the mechanical properties were investigated.Multilayer scaffolds were constructed using the preparecl PDS stent as the middle elasticity layer and covering it with small intestinal submucosa(SIS).To reinforce the scaffold,the outer two lavers were continuously sutured with 8-0 PDS suture perpendicular to the longitudinal axis.The inner layer of scaffold was coated With collagen sponge which was added with 10%chondroitin sulfate(CS).The biomechanical properties of the scaffold such as burst strength,tensile strength and compliance were tested and compared to those of canine carotid artery.Results 65-degree weaving angle was chosen to construct stent with 4 mm inner diameter and 3 to 5 cm length.These scaffolds had(43.50±8.30)kPa burst strength,(19.10±1.56)N tensile strength,(42.88±3.16)% strain ratio and(5.96±0.87)%/100 mm Hg radial compliance.Conclusion The multilayer scaffolds have satisfactory biomechanical properties that meet the mechanical requirements for in vivo implantation as a tissue engineered blood vessel.