ABSTRACT
Mechanical stresses in the aortic valve may determine the longevity of the valve because occurrence of excessive stresses can damage the valve and perhaps cause certain types of valvular pathology. To determine mechanical stress in a leaflet it is necessary to know the stress-strain properties, the loading conditions, and the type of deformation to which the leaflet is subjected. Stress-strain properties of a leaflet have been investigated in two different ways: uniaxial stress-strain properties and stress-strain properties of a leaflet in an intact closed valve. The stress analysis of most biological structures presents a challenging problem, because biological tissues are inhomogeneous, anisotropic, nonlinear, and generally viscoelastic and the structures usually have a complex geometry. Stress analysis requires knowledge of the geometry of the valve, material properties of the leaflets, and loading conditions. The geometry of the valve was determined from several silicone rubber molds made of closed human aortic valve.
