The aortic valve is the heart valve between the left ventricle and the aorta and is one of four valves in the heart. This valve is susceptible to diseases such as aortic stenosis. First performed in 2002 and approved in the US as recently as 2011, Transcatheter Aortic Valve Replacement (TAVR) is an effective, less-invasive treatment for high- and intermediate-risk patients suffering from aortic valve diseases. Towards the development of modelling approaches for fatigue life assessment of TAVR systems under in-vivo and in-vitro (pulse duplicator) loading conditions, the impact of bioprosthetic valve leaflet material properties should be considered. The leaflets considered in this study are porcine pericardium. Variations in leaflet stiffness can be as large as two orders of magnitude and dependent on various factors, including pericardium source, leaflet chemical and preservation treatment and collagen fibre orientation within the leaflets. It is also well known that porcine pericardium tissue used for the prosthetic valves exhibits mechanical anisotropy. The aim of this study is to correlate leaflet constitutive behaviour to the nitinol stent frame deformations and ultimately understand the impact of the pericardium behaviour on the nitinol stent fatigue life. An explicit dynamics finite element model of the nitinol stent with attached porcine pericardium leaflets was built in the commercial software Abaqus (version 2021). The model was used to evaluate the deflection and corresponding stresses of the stent frame posts (commissures) due to the haemodynamic loads acting on the leaflets. The nitinol stent frame was represented as a super-elastic material based on experimental testing. The porcine pericardium behaviour under biaxial testing performed by Li et al was used as a baseline for the numerical study, and the leaflet was described using the Ogden isotropic model and Holzapfel-Ogden anisotropic model with varying collagen fibre orientations. A reasonable correlation has been found between the deflection measurements taken for the stent posts operating under a pulse duplicator. In particular, the leaflet “pinwheeling” effect is captured, where the three leaflets locally rotate at the centre point. Results indicate that the pericardium behaviour appears to be a more dominant mechanism for dictating stent frame deflection than initially expected. Particularly, the inclusion of anisotropy and, importantly, the orientation of collagen fibres within the leaflet, can influence the extent of the deflection encountered by each of the three nitinol stent frame posts. The variation of stent post deflection in turn affects the fatigue strain of the nitinol stent.