his
figure shows the flow pattern in a thin section through a model
heart in the neighborhood of the aortic valve during ventricular
ejection. Aortic structures are shown in yellow (other parts of
the heart model are not shown). The flow pattern is represented
by streamlines, which are calculated from the 3-D velocity field
at the instant shown. Flow is passing from the left ventricle
upward through the aortic valve into the aorta. Note the prominent
vortex in the cavity behind the valve leaflet, near the left center
of the figure. There is such a cavity, known as an aortic sinus,
behind each of the three leaflets of the aortic valve. Because
of the orientation of the valve relative to the plane of the section,
the vortex in only one of these sinuses is visible. Vortices such
as these are believed to play an important role in closing the
aortic valve when ejection is complete. 
.
|
|