A normal aortic valve is composed of three aortic-valve cusps, each semilunar in appearance. The leaflets are housed within a small dilatation of the proximal aorta associated with each cusp, called the sinuses of Valsalva or aortic sinuses, and their association with the respective coronary ostia identifies them: left, right, and non-coronary sinuses. Each cusp is attached to the wall of the aorta by the outward edges of its semicircular border, and the attachment point between each leaflet is called a commissure [PMID:24827036].