FIG. 2.

Major forces affecting aortic valve. (A) Main forces acting during systole on the valve. The ventricularis is stretched, while the fibrosa is compressed, generating a bending stress in the valve. Blood ejection from the heart exerts unidirectional laminar shear stress on the ventricularis (red arrow). (B) The main forces acting during diastole. Pressure (cyan arrows) is applied to the valve as the ventricle relaxes, and axial stress (purple arrows) prevents regurgitation by sealing the valve. The fibrosa experiences low oscillatory shear stress (red arrow). To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/ars