The aortic valve separates the left ventricular outflow tract from the ascending aorta. The aortic
valve has also been called the left semilunar valve and the left arterial valve and has three
leaflets, or cusps: the left coronary cusp, the right coronary cusp, and the non-coronary cusp. The
inlets to the coronary artery system can be found within the sinus of Valsalva, superior to the the
leaflet attachments and inferior to the sinotubular junction. The left coronary ostium is found
midway between the commissures of the left coronary cusp, and almost immediately branches into the
anterior interventricular branch and the circumflex branch. The right coronary ostium is found
above the right coronary cusp and gives rise to the right coronary artery. The final cusp is named
the non-coronary cusp and is positioned posteriorly relative to the other two cusps.
The mitral valve is also called the bicuspid valve and the left atrioventricular valve. As the name
bicuspid valve may suggest, the mitral valve is considered to have two primary leaflets: the
anterior and posterior leaflets. The anterior leaflet has also been called the septal, medial, or
aortic leaflet, while the posterior leaflet is also referred to as the lateral, marginal, or mural
leaflet. Each leaflet is then further broken down into scallops divided by commissures, or zones of
apposition. Due to the high variability of leaflet and scallop anatomy, and an alphanumeric
nomenclature has been proposed by Carpentier that breaks the leaflets into regions. Three regions
are found on the anterior leaflet (A1-A3) with opposing regions on the posterior leaflet (P1-P3).
The subvalvular apparatus of the mitral valve consists of chordae tendinae attaching to the anterior
and posterior papillary muscles of the left ventricle.