A Growth-Based Computational Model of Aortic Dissection Morphogenesis*

Aortic dissections originate with a tear in the inner layer of the aortic wall, compromising its integrity and creating a mechanically unstable system. As the human body’s largest pressurized vessel, the aorta is a complex structure composed of hyperbolic and cylindrical sections. This geometric complexity influences dissection evolution as well as suitability for different modalities of clinical treatment. Concurrently, progression of aortic dissection is marked by dynamic shape changes over time. As such, predicting this deformation is a challenge with major implications in treatment of aortic diseases. We used a finite element analysis (FEA) computational model of the aorta’s complex geometry and anisotropic fiber composition (with the Ogden-Gasser-Holzapfel constitutive model) that incorporates pressurization and growth to predict shape change of aortic dissections over time. We modeled deformation of an aorta from a dissection patient with initial minimal pressurization followed by isotropic growth in the longitudinal and circumferential directions. We observed that the resulting geometry predicted by the FEA model closely replicates the patient’s true dissection evolution.Further refining our computational model may help improve treatment for aortic diseases.