Left atrial ball-valve thrombus

Mitral valve replacement is a procedure whereby the diseased mitral valve of a patient's heart is replaced by either a mechanical or tissue (bioprosthetic) valve. The mitral valve may need to be replaced because: The valve is leaky (mitral valve regurgitation) The valve is narrowed and doesn't open properly (mitral valve stenosis)Causes of mitral valve disease include infection, calcification and inherited collagen disease. [Source: Wikipedia ]