Mitral valve of blood through the valve. The word "mitral" comes from Latin, meaning "shaped like a mitre" (bishop's hat). The word "bicuspid" uses combining forms of "bi-", from Latin, meaning "double", and "cusp", meaning "point", reflecting the dual-flap shape of the valve. Mitral valve The mitral valve (), also known as the bicuspid valve or left atrioventricular valve, is a valve with two flaps in the heart, that lies between the left atrium and the left ventricle. The mitral valve and the tricuspid valve are known collectively as the atrioventricular valves because they lie between the atria and the ventricles of
Mitral insufficiency MR and mitral valve prolapse are also common in Ehlers–Danlos syndromes. Secondary mitral insufficiency is due to the dilatation of the left ventricle that causes stretching of the mitral valve annulus and displacement of the papillary muscles. This dilatation of the left ventricle can be due to any cause of dilated cardiomyopathy including aortic insufficiency, nonischemic dilated cardiomyopathy, and Noncompaction cardiomyopathy. Because the papillary muscles, chordae, and valve leaflets are usually normal in such conditions, it is also called functional mitral insufficiency. Acute MR is most often caused by endocarditis, mainly "S. aureus". Rupture or dysfunction of the papillary muscle