[Biomechanical characterization of the wall of abdominal aortic aneurysm exposed to infection].

Presented herein are three cases of biomechanical evaluation of the wall of the normal abdominal aorta, of the wall of an abdominal aortic aneurysm infected by Chlamydia pneumoniae, and of the wall of an abdominal aortic aneurysm uninfected by Chlamydia pneumoniae. The samples of the aortic wall and aortic aneurysm were tailored in two directions--transverse and longitudinal. The samples were inserted into the appliance 858 Mini Bionix produced by the MTS for testing the strength of materials and stretched at a constant speed. Based on the studies performed there were obtained the "tension-deformation" curves on which the points of resistance and plasticity were plotted. It has been established that the presence pneumoniae in the abdominal aortic wall favours a significant decrease in the maximal magnitude of the tension in the wall of abdominal aortic aneurysm. As compared to the wall of the abdominal aortic aneurysm, the wall of the normal abdominal aorta demonstrated the higher tension in the transverse direction than in the longitudinal whereas the wall of abdominal aortic aneurysm showed the greater tension in the longitudinal direction.