A Poroviscoelastic Model of Intraluminal Thrombus From Abdominal Aortic Aneurysms

Computational models, developed to study abdominal aortic aneurysm (AAA) biomechanics, demonstrated that the presence of an intraluminal thrombus (ILT) can significantly alter the wall stress distribution in the degenerated vessel wall [1,2]. ILT is a soft hydrated tissue constituted of 90% of water. The solid porous matrix is made of a fibrin lattice entrapping solid aggregates, mostly platelets [3].. Although the ILT is subjected to compression in vivo, up to now ILT constitutive models have been based on parameters derived from tensile testing of ILT specimens [1]. The aim of this study was to define the biomechanical properties of ILT under compressive loads, using a combined experimental-numerical approach. ILT samples were tested for unconfined compression and permeation. A poroviscoelastic model was implemented to interpret the experimental data.