DIRECTIONAL DIFFERENCES IN THE BIOMECHANICAL PROPERTIES OF ASCENDING AORTIC ANEURYSMS

摘要

The present study aimed to examine directional differences in the biomechanical properties of ascending aortic aneurysms. Fresh tissue from patients undergoing graft replacement of the ascending aorta was classified according to direction and submitted to biomechanical testing beyond rupture. In the majority of tests, the inner layers of the aortic wall ruptured first, and tensile strength and maximum tissue stiffness were significantly higher in the circumferential compared to the longitudinal direction. The present findings relating to directional differences in the biomechanical properties of aneurysmal tissue should be considered together with wall stresses predicted from finite element analyses, offering an explanation as to why aneurysmal dissections may occur in the aortic intima with a circumferential tear.