Aortic valve leaflets (anatomy)

The aortic valve leaflets are three in number:

• right
• left
• posterior

As with the other heart valves:

• each leaflet has a central lamina fibrosa which is attached to the fibrous annulus of the valve
• surrounding the lamina fibrosa is a layer of endocardium

However, the aortic valve leaflets are notable for:

• prominent thickening of the lamina fibrosa at the centre of the free margin of each leaflet; forms the fibrous nodules of each leaflet. When the valve is closed, the three nodules meet centrally.
• the leaflets being thicker than those of the pulmonary valve
• the region between the leaflets being relatively thin due to a paucity of fibrous tissue - the lunules of each cusp
• the aortic surface of the endocardium being rougher in nature than the ventricular surface
• the aortic sinuses lying superior to each leaflet

There is some variability as to the terminology of the various valves - see submenu.