The optimized material properties were implemented in FE simulations of transcatheter aortic valve (TAV) deformation.
Just before crossing the aortic valve, a deformation of the cobalt chromium stent with an outward bending of two struts was observed, which had been caused by resistance of endogenous calcium plaques in the descending aorta during catheter introduction (figure 1A and D).
The specialized properties of the myocardium and valvular tissues, including the capability of contraction of cardiac tissue and the deformation of valves, provide obstacles for the fabrication of tissue-engineered implants for cardiac interventions.
A fictitious domain method extended with a local mesh adaptation algorithm provides the required flexibility with respect to the motion and deformation of the valve.
Nonlinear FEA in ANSYS using the fluid pressure penetration (FPP) technique revealed that there is a limited amount of fluid penetrating into gap, which is caused by the plastic deformation of the valve seat at the macroscale.
By the calculation results, the evolution laws with time and space are revealed regarding to the pressure and temperature of the fluid in the chambers, and the temperature, stress and deformation of the valve plate friction pair, the wedge-shaped clearance forms between them, even mixed friction occurs, and the corresponding improving measures aimed at the discovered problems are discussed.
According to the boundary conditions, tensile deformation of the valve can be obtained as follows: Delta = intlimits_{{r_{1} }}^{{r_{2} }} {frac{{qr_{2} cos theta }}{{Et_{m} varphi (x)}};{text{d}}x} = frac{{qr_{2} cos theta }}{{Et_{m} varphi (x)}}ln frac{{r_{2} }}{{r_{1} }}.
(13)The tensile deformation of the valve is varepsilon = frac{dDelta }{{rm d}x} = frac{F}{EA} = frac{{qr_{2} cos theta }}{{Et_{m} varphi (x)}}, (14 where A is the cross-sectional area of the valve, and Δ is a tensile variable of the valve.
The name comes from the joint problem, which resembles rheumatism, but the most dangerous consequence is the deformation of heart valves.
The results of this study showed that the anisotropic Fung model accurately simulated the leaflet deformation and coaptation during valve opening and closing.
