Biomechanical characteristics of the abdominal aortic wall

Abstract

Background. The structure of the aorta wall is well adapted to withstand the mechanical loads caused by arterial blood pressure. The most important structural components of the aortic wall are elastin and collagen fibres. Elastin and collagen fibres allow reversible deformation of, and give mechanical strength to, the aorta. Alterations in composition cause changes in the mechanical properties of the aortic wall. Hence, the main aim of this study is the biomechanical assessment and preliminary histological study of the abdominal aortic wall.
Material and methods. Specimens were cut from the materials obtained during autopsies, taking research standards into consideration, which were then examined in order to determine the directional material properties. The second part of the materials was intended for histological analysis.
Results. It was appreciable that the mechanical strength of the aortic wall is higher in the transversal than in the longitudinal direction, which has a vital meaning for the correct functioning of the organism, and it makes the vessel able to perform reversible deformation under the influence of pulsatile blood pressure. This ability is strongly dependent on the structural composition of the aortic wall.
Conclusions. Structural alterations due to atherosclerotic lesions of various degrees lead to a significant increase of stiffness and decrease of mechanical strength of the walls of abdominal aorta.