<unk>  <unk>  is  a disorder of the heart in which  the<unk>  valve does not close properly when the heart pumps out blood. <unk>  is the abnormal leaking of blood from the left ventricle through the<unk>  valve, and into the left atrium, when the left ventricle contracts. <unk>  is the most common form of valvular heart disease.<unk>  can be classified into either acute or chronic according to the acuity of the events leading to the valvular abnormality. Regardless of the underlying etiology of<unk> , a decrease in the coaptation between the leaflets of the valve commonly characterizes all cases of<unk> . The causes of<unk>  depend on the acuity of the valvular abnormality and the underlying pathological mechanism. The blowing holosystolic murmur of<unk>  must be distinguished from tricuspid regurgitation and a ventricular septal defect.<unk>  is one of the most common valvular diseases in the general population, ranking first among valvular regurgitation abnormalities. The prevalence of<unk>  of a severity equal to or worse than mild was reported in The Framingham Heart Study as 19.0% in men and 19.1% in women.  The prevalence of<unk>  increases with age.  Chronic<unk>  can be either compensated or decompensated. The natural history and prognosis of<unk>  depend on the underlying etiology and the degree of severity of the valvular abnormality.  Mild<unk>  is associated with few if any complications. The stage of<unk>  can be estimated based on specific criteria for the valve anatomy, valve hemodynamics, associated cardiac findings, and symptoms.
Mitral regurgitation
Aortic regurgitation
Tricuspid regurgitation
Mitral stenosis
Functional mitral regurgitation
Pulmonic regurgitation
Mitral valve prolapse
Aortic stenosis