Surgical repair of congenital aortic regurgitation by aortic root reduction: A finite element study.
Surgical repair of congenital aortic regurgitation by aortic root reduction: A finite element study.
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DOI：
10.1016/j.jbiomech.2015.09.030
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发表时间：
2015-11-05
影响因子：
2.4
通讯作者：
del Nido PJ
中科院分区：
文献类型：
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作者：
Hammer PE;Berra I;del Nido PJ
在儿童主动脉瓣外科重建术中，由于移植物不能与儿童一起生长并加速结构退化，使用异种移植物材料可能会限制修复的耐久性。在这项研究中，我们使用计算机模拟和体外实验来探索一种外科修复方法，这种方法有可能在不引入移植物材料的情况下治疗一种特殊形式的先天性主动脉瓣反流。具体地说，对于因先天叶过小而返流的主动脉瓣，我们建议切除属于正常叶之一的部分主动脉根部，以改善瓣膜关闭和消除返流。我们使用主动脉瓣的结构有限元模型来模拟关闭的加压瓣膜，采用不同的手术方法(例如，三角形和矩形切除)切除主动脉根部。结果表明，主动脉根部减压术可以改善瓣膜关闭和消除返流，但其效果与切除部位的形状和大小密切相关。只有在瓣环水平上缩小主动脉根部大小的切除策略才能改善瓣膜关闭，只有切除一大块矩形部分的策略-延长根部的完整高度并将根部直径缩小约12%-才能消除返流并产生适当的修复。离体猪主动脉的体外验证实验证实了模拟结果。
During surgical reconstruction of the aortic valve in the child, the use of foreign graft material can limit durability of the repair due to inability of the graft to grow with the child and to accelerated structural degeneration. In this study we use computer simulation and ex vivo experiments to explore a surgical repair method that has the potential to treat a particular form of congenital aortic regurgitation without the introduction of graft material. Specifically, in an aortic valve that is regurgitant due to a congenitally undersized leaflet, we propose resecting a portion of the aortic root belonging to one of the normal leaflets in order to improve valve closure and eliminate regurgitation. We use a structural finite element model of the aortic valve to simulate the closed, pressurized valve following different strategies for surgical reduction of the aortic root (e.g., triangular versus rectangular resection). Results show that aortic root reduction can improve valve closure and eliminate regurgitation, but the effect is highly dependent on the shape and size of the resected region. Only resection strategies that reduce the size of the aortic root at the level of the annulus produce improved valve closure, and only the strategy of resecting a large rectangular portion-extending the full height of the root and reducing root diameter by approximately 12% – is able to eliminate regurgitation and produce an adequate repair. Ex vivo validation experiments in an isolated porcine aorta corroborate simulation results.