Trowbridge E A, Crofts C E
Biomaterials. 1986 Jan;7(1):49-54. doi: 10.1016/0142-9612(86)90089-x.
Natural and glutaraldehyde fixed bovine pericardium samples were mechanically conditioned by a cyclic uniaxial load procedure. The samples tested were controlled for both position and direction in the pericardial sac. The natural tissue demonstrated a significant increase in length and a significant decrease in width after mechanical conditioning. The deformations were not permanent. The test specimens had returned to their original length by 10.5 h after the mechanical test. The control samples of natural tissue showed no significant changes in length during this time. The chemically modified tissue showed a significant increase in length but no significant changes in width or thickness after mechanical conditioning. As in the natural tissue, the length changes were not permanent. Twenty four hours after returning the fixed tissue to its normal buffered glutaraldehyde storage medium the test samples had returned to their original length. A subsequent mechanical retest 8 d after the initial test procedure suggested that the history of the original test had been removed. These observations may be important in the interpretation of 'in vitro' hydrodynamic tests for heart valve substitutes.
天然和经戊二醛固定的牛心包样本通过循环单轴加载程序进行机械预处理。所测试的样本在心包囊中进行了位置和方向的控制。机械预处理后，天然组织的长度显著增加，宽度显著减小。这些变形并非永久性的。机械测试后10.5小时，测试样本恢复到了原始长度。在此期间，天然组织的对照样本长度未出现显著变化。化学改性组织在机械预处理后长度显著增加，但宽度和厚度未出现显著变化。与天然组织一样，长度变化并非永久性的。将固定组织放回其正常的缓冲戊二醛储存介质中24小时后，测试样本恢复到了原始长度。在初始测试程序8天后进行的后续机械复测表明，原始测试的影响已消除。这些观察结果对于解释心脏瓣膜替代物的“体外”流体动力学测试可能很重要。
