Mitral valve chordae attached to the posterior cusp. Advanced lesions—also commonly involving the posterior leaflet—lead to leaflet folding, inversion, and displacement toward the left atrium. A valve prolapse can result in mitral insufficiency which is a regurgitation or backflow of blood due to the incomplete closure of the valve. Rheumatic heart disease often affects the mitral valve. The valve may also be affected by infective endocarditis Surgery can be performed to replace or repair a damaged valve. A less invasive method is that of mitral valvuloplasty which uses a balloon catheter to open up a stenotic valve. Rarely there can be a
Mitral valve prolapse "atrialis", "fibrosa", and "spongiosa". Patients with classic mitral valve prolapse have excess connective tissue that thickens the spongiosa and separates collagen bundles in the fibrosa. This is due to an excess of dermatan sulfate, a glycosaminoglycan. This weakens the leaflets and adjacent tissue, resulting in increased leaflet area and elongation of the chordae tendineae. Elongation of the chordae tendineae often causes rupture, commonly to the chordae attached to the posterior leaflet. Advanced lesions—also commonly involving the posterior leaflet—lead to leaflet folding, inversion, and displacement toward the left atrium. Echocardiography is the most useful method of diagnosing a prolapsed mitral valve.