Tricuspid valve contains anterior (largest), posterior, and medial leaflets.
Pulmonic valve contains the anterior, right, and left cusps and is 4 cm2 in area.
Mitral valve is normally 4-6 cm2 and is made up of the anteromedial and posterolateral leaflets. The blood supply to the mitral chordae tendinae and papillary muscles is often in jeopardy. [Lam JHS et al. Circulation 41: 449, 1970] The left circumflex or right coronary artery (depending on dominance) provides the blood supply to the postero-medial papillary muscle. Because of its single system of blood supply, this papillary muscle is particularly prone to injury from myocardial infarction.
Aortic valve is made of the posterior (noncoronary), and left (coronary) and right (coronary) cusps. It is 3-4 cm2, about the same as the pulmonic valve.