Hajizadeh Farkoush Siamak, Abolfathi Nabiollah, Mehmanesh Hormoz, Najarian Siamak
a 1 Faculty of Biomedical Engineering , Amirkabir University of Technology , Tehran, Iran.
b 2 Department of Cardiovascular Surgery, Erfan Grand Hospital , Tehran, Iran.
Minim Invasive Ther Allied Technol. 2016;25(1):15-21. doi: 10.3109/13645706.2015.1054838. Epub 2015 Aug 28.
Aortic cross-clamping is a critical action during heart surgeries which may cause some injuries to the wall of the artery. These injuries may have both short-term and long-term adverse effects on the artery function. Appropriate clampers can properly occlude the artery and decrease the extent of injury. Thus, developing a model for evaluation of such clampers is inevitable. In this paper, a finite element model of the aorta is presented; then, different mechanisms of clamping are investigated. In this regard, a numerical model of aortic cross-clamping by three types of clampers has been implemented with consideration of nonlinear behavior of two-layer artery, residual stress in aorta, and calcification. These three clamper models are commercial Chitwood clamper and linear mechanism clamper with and without balloon. Using the obtained results, comparative analysis was performed between the proposed clamper design and the commercial one. Based upon the analysis, it was concluded that the designed clamper, linear mechanism clamper with balloon, helps to distribute the stress uniformly in different layers of the aorta, which results in better performance of the clamping procedure and causes less injury in the aorta, especially when there is calcification.
主动脉交叉钳夹是心脏手术中的关键操作，可能会对动脉壁造成一些损伤。这些损伤可能对动脉功能产生短期和长期的不利影响。合适的钳夹器能够正确地阻断动脉并减少损伤程度。因此，开发一种评估此类钳夹器的模型是必不可少的。本文提出了一种主动脉的有限元模型；然后，研究了不同的钳夹机制。在这方面，考虑到双层动脉的非线性行为、主动脉中的残余应力和钙化，实现了三种类型钳夹器对主动脉交叉钳夹的数值模型。这三种钳夹器模型分别是商用奇伍德钳夹器以及带气囊和不带气囊的线性机械钳夹器。利用所得结果，对所提出的钳夹器设计与商用钳夹器进行了对比分析。基于该分析得出结论，所设计的带气囊线性机械钳夹器有助于在主动脉的不同层中均匀分布应力，从而使钳夹过程表现更好，并且在主动脉中造成的损伤更小，尤其是在存在钙化的情况下。
