Surgical management of thoracic aortic aneurysms is based on the maximum diameter of the aorta. However, this criterion is not robust and it appears necessary to complement it with other parameters that take into account the biomechanics of the aorta. The aim of this project is to develop a patient-specific pathological aorta model from MRI, and to extract predictive biomechanical markers of aneurysm rupture. This model will be designed from a population of 100 patients. Specific markers of rupture of aneurysms modelled from MRI may be a combination of elasticity, strain, parietal stress or parameters characterising blood flow within the aorta such as vorticity and helicity. Ex-vivo biomechanical studies of the aortic tissue collected during the patient’s surgery, as well as histological studies of these samples, will generate and validate this modeling. The biomechanical parameters ex-vivo will be deduced in particular from Young’s module and histological studies will make it possible to have a precise idea of the composition of the aortic tissue (especially in collagen). The objective is to graduate the clinical condition of the patient, to be able to detect early patients at risk of rupture of aneurysm, even if their diameter of the aorta did not reach the threshold value for surgery.