The microstructure evolution of the aortic tissue in cardiovascular pathologies, such as aneurysm or arthrosclerosis, leads to an overall change of biomechanical properties. Successful treatment (e.g endovascular) of these pathologies depends on the comprehension of these properties and on the surgeon expertise.

Many investigators have created general-purpose aortic replicas called “phantoms”, for the preoperative training and/or the studies of surgical and radiological processes. However, the importance of the used material properties was generally neglected. Moreover, the specific shape and the mechanical behavior of each patient’s aorta were not taken into account. Our work aims to create patient-specific phantoms able to accurately mimic each individual case.

We use a mechanical model comprising both hyperelastic and viscoelastic behaviors which can be scrutinized to predict aneurysm rupture and to diagnose the atherosclerosis, respectively. To identify the model parameters, we performed steady and dynamic ex-vivo experiments. Results were used to develop a large range of materials able to replicate real healthy and pathologic aortic mechanical behavior. For that purpose, different Bluesil® silicone materials from Bluestar Silicones Company were used and suitably formulated. After adjusting the material formulation, the specific aorta shape given by medical imaging is encoded in a finite element model in order to manufacture the specific phantom by 3D prototyping. The whole process results in a quick production of a specific phantom that can be positioned in a hydro-dynamic test bench, in which physiological hemodynamic conditions can be simulated and the model parameters can be verified from ultrasound images and pressure measurements.