The biomechanics of arterial aneurysms

The formation of an arterial aneurysm is believed to be a multifactorial and predominantly degenerative process, resulting from a complex interplay between biological processes in the arterial wall and the hemodynamic stimuli on the vessel's wall. Once an aneurysm forms, the repetitive pressure and shear stresses exerted by the blood flow on the weakened arterial wall generally, but not always, cause a gradual expansion. As the wall geometry, composition, and strength progressively degrade through the enlargement process, the aneurysm ruptures when the wall of the distended artery fails to support the stresses resulting from the internal blood flow. This review surveys recent progress in this area and provides a critical assessment of the contribution made by hemodynamics studies to the current understanding of the pathogenesis of the disease and to its clinical management.