Braile Biomédica Indústria Comércio e Representações SA, São José do Rio Preto, São Paulo, Brazil.
Artif Organs. 2011 May;35(5):497-501. doi: 10.1111/j.1525-1594.2011.01262.x.
Calcification is one of the major causes of failure of heart valve bioprostheses (HVBs) derived from glutaraldehyde (GA)-processed bovine pericardium (BP) or porcine aortic valves. New crosslinking reagent procedures are still far from giving satisfactory results, and this is the main reason why GA is still the reagent of choice for the fixation of native tissue intended for HVB manufacture. Nevertheless, two new findings with respect to GA processing may significantly improve HVB performance postimplantation: the finding that increasing concentrations of GA result in a decrease in calcification; the blocking of free aldehyde usually by nucleophyles or the treatment of processed material at low pH. This work investigates the in vitro properties of BP fixed with GA followed by the treatment with glutamic acid under alkaline conditions in order to prepare BP materials with lower calcification potential postimplantation. In comparison to conventional processing, except for the tensile strength that was slightly lower, elongation and toughness were higher than the accepted values. No significant differences were observed in the performance indexes (mean pressure gradient, mean effective area, regurgitant fraction, performance and efficiency indexes) with wear resistance over 150 × 10⁶ cycles. These results indicate that the processing of BP described in this work may be of potential use in the manufacture of HVBs.
钙化是导致戊二醛（GA）处理的牛心包（BP）或猪主动脉瓣生物瓣（HVB）失效的主要原因之一。新的交联试剂处理方法仍远未达到令人满意的效果，这也是 GA 仍然是用于制造 HVB 的天然组织固定的首选试剂的主要原因。然而，GA 处理的两个新发现可能会显著改善植入后的 HVB 性能：发现 GA 浓度的增加会导致钙化减少；通常通过亲核试剂或在低 pH 值下处理加工材料来阻止游离醛。本研究旨在探讨 GA 固定后再用谷氨酸在碱性条件下处理的 BP 的体外性能，以制备植入后钙化潜力较低的 BP 材料。与传统处理方法相比，除了拉伸强度略低外，伸长率和韧性均高于可接受值。经过 150×10⁶ 次循环的耐磨性测试，在性能指标（平均压力梯度、有效瓣口面积、反流分数、性能和效率指数）方面未观察到显著差异。这些结果表明，本研究中描述的 BP 处理方法可能有潜力用于制造 HVB。
