复合鞣制方法处理生物瓣膜生物材料性能评估

The functional appraisal of the biological materials compoundly tanned for prothetic valve

目的 对复合鞣制方法处理的生物材料性能及生物瓣膜临床应用效果进行评估。方法 对比用戊二醛、阳离子油、三氧化二铬及甘油等复合鞣制的生物材料和单纯戊二醛鞣制生物材料的组织钙含量。对生物材料进行组织学、超微结构和机械抗张强度测试 ,用傅立叶红外光谱仪测定羧基含量。生物瓣膜经体外模拟疲劳寿命实验台加速检测。结果 复合鞣制生物材料组织钙含量低 ,组织胶原纤维结构排列致密、整齐 ,细胞结构完整 ,收缩温度在 86～ 90℃时生物材料最柔软 ,抗张强度 199～ 2 5 9N/mm2 ,延伸率 4 34%～ 4 6 0 % ;红外光谱图显示羧基 (COOH-1)峰明显降低 ;体外模拟加速疲劳实验台测试 ,猪主动脉瓣膜能经受 3892亿次循环 ,牛心包瓣膜为 3888亿次 ,从受力疲劳方面看将能经受住大约 10年的寿命。结论 用复合鞣制方法处理生物材料 ,可提高生物瓣膜的柔软性和强度 ,对生物瓣膜的防钙化起重要作用。

Objective: To evaluate biological materials tanned with a compound method for clinical performance of biovalves. Methods: The tissue calcium concentration was compared between biological materials tanned simply with amylic aldehyde and those compoundly tanned with amylic aldehyde, cation fat, chromium trioxide and glycerol. The histological morphology, the ultra-structure and tensile strength of the biological materials were tested and the content of hydroxyls in the materials was measured with the Fourier infrared spectrum detector. The prosthetic biological cardiac valves made of the materials were tested with an accelerated wearing device extracorporeally. Results: The tissue calcium concentration was lower in the compoundly tanned materials. In these materials, the collagenous fibers were dense and lined up in order. The cellular structure was maintained. The materials were pliable at the contracting temperature of 86℃ to 90℃. The tensile strength of the materials was 19.9 to 25.9 N/mm 2 and the extension rate was 43.4% to 46.0%. The peak of the hydroxyls decreased significantly at the wave length of 1741.11 cm -1 in the Fourier infrared spectrum. The swine aortic valve experienced 3.892×10 8 cycles in the accelerated wearing tests, and the bovine pericardial valve, 3.888×10 8 cycles. By estimation, the biovalves will last for about ten years. Conclusion: Compound tanning can increase firmness and softness of the materials and may play an important role in anticalcification of the biovalves.