<unk>  <unk>  is a multifactorial chronic degenerative process in which calcium with lipid is deposited (calcified) in the<unk>  fibrosa ring of the heart's mitral valve.<unk>  was first discovered and described in 1908 by M. Bonninger in the journal Deutsche Medizinische Wochenschrift. In the majority of cases, affected patients are asymptomatic and the condition is only noted incidentally on echocardiography or computed tomography (CT) scans. However,<unk>  remains clinically significant because while in many cases the<unk>  is limited to the annulus and proximal leaflet bases, it may also extend further into the valve structure. This may potentially cause mitral regurgitation (MR) or more rarely mitral stenosis (MS), which may produce the classic symptoms of these conditions over time. In addition,<unk>  of the annulus can inhibit electrical conduction of the AV node, consequently causing various degrees of heart block. While<unk>  does not usually necessitate treatment independently, the degree of<unk>  present in the annulus is an important factor in choosing the most appropriate treatment modality for several conditions that do require intervention, particularly those that cause symptomatic obstruction of left ventricular outflow (LVOT).
Mitral annular calcification
Bicuspid aortic valve
Quadricuspid aortic valve
Supravalvular aortic stenosis
Flutter valve
Mitral annular disjunction
Accessory auricle
Overriding aorta