Kozuń Marta, Płonek Tomasz, Jasiński Marek, Filipiak Jarosław
Wrocław University of Science and Technology, Faculty of Mechanical Engineering, Department of Biomedical Engineering, Mechatronics and Theory of Mechanism, Wrocław, Poland.
Wrocław Medical University, the Clinic of Cardiac Surgery, Wrocław, Poland.
Acta Bioeng Biomech. 2019;21(2):127-134.
The aim of the presented work is to determine (i) mechanical properties of the ascending aorta wall (DAA) and the wall of the ascending aortic aneurysm (DAAA), in which spontaneous dissection resulting from the evolving disease occurred, and (ii) the strength of the interface between the layers in the above-mentioned vessels.
The mechanical tests were divided into two steps. In the first step the mechanical properties of the of DAA and DAAA walls were examined on the basis of uniaxial stretching until rapture. In the next step the mechanical parameters of the interface between layers of DAA and DAAA walls were determined by the peeling test.
Higher values of tensile strength ( max) and Young's modulus (E) were obtained for the DAAA group, to which the dissecting wall of the ascending aortic aneurysm was classified. For circumferential samples, the difference between the DAAA and DAA groups was 39% in the case of tensile strength and 70% in the case of the Young's modulus.
Summarizing, the studies performed showed that the dissection process is different in the case of the ascending aortic aneurysm wall and the ascending aorta wall. The wall of the ascending aortic aneurysm is more susceptible to dissection, as evidenced by lower values of the mechanical parameters of the interface between the intima and the media-adventitia complex. The obtained results of mechanical properties tests confirm that dissection and aneurysm should be treated as separate disease entities that may coexist with each other.
本研究的目的是确定（i）升主动脉壁（DAA）和升主动脉瘤壁（DAAA）的力学性能，其中升主动脉瘤壁发生了由疾病进展导致的自发夹层，以及（ii）上述血管各层之间界面的强度。
力学测试分为两个步骤。第一步，基于单轴拉伸直至破裂来检测DAA和DAAA壁的力学性能。第二步，通过剥离试验确定DAA和DAAA壁各层之间界面的力学参数。
将发生夹层的升主动脉瘤壁归为DAAA组，该组获得了更高的拉伸强度（σmax）和杨氏模量（E）值。对于周向样本，DAAA组和DAA组在拉伸强度方面的差异为39%，在杨氏模量方面的差异为70%。
综上所述，所进行的研究表明，升主动脉瘤壁和升主动脉壁的夹层过程有所不同。升主动脉瘤壁更容易发生夹层，内膜与中膜-外膜复合体之间界面的力学参数值较低证明了这一点。力学性能测试的结果证实，夹层和动脉瘤应被视为可能相互共存的不同疾病实体。
