Computational methods for the analysis of ascending aortic aneurysms

Thoracic aortic aneurysm is a disease which affects 5.3 per 100,000 individuals per year. Degenerative processes cause a weakening of the aortic wall and a dilatation of the vessel. Under the standard clinical practice, the severity of an aneurysms is evaluated considering its dimensions exclusively. However, this procedure is not able to capture the patient-specific condition. In order to shed some light on the state and integrity of the blood vessels under physiological conditions prior to performing a surgery, computational tools can be used. This thesis presents a series of computational solutions for the assessment of both the hemodynamic and structural condition of ascending thoracic aneurysms. In first instance, an analysis of the optimal computational strategy for the modelling of hemodynamic flows is presented. In particular, the effect of different turbulence and viscosity models on wall shear stress biomarkers is assessed. In second instance, after having defined the optimal computational strategy for computational fluid dynamics (CFD) analyses, the correlation between CFD derived biomarkers and aneurysm growth rate is examined. Lastly, in order to provide a more complete picture of the aneurysm condition by including the structural domain, a methodology for the creation of high-fidelity fluid-structure interaction aorta models is presented.