What is the most common cause of mitral regurgitation?

Myxomatous degeneration is recognized as the most common cause of mitral regurgitation, particularly in the context of primary degenerative mitral valve disease. This condition often manifests as a degeneration of the valve leaflets and supporting structures, resulting in a pathological elongation and displacement of the chordae tendineae. This leads to improper closure of the mitral valve during systole, causing regurgitation of blood from the left ventricle back into the left atrium.

Myxomatous degeneration is frequently seen in younger individuals and can be associated with connective tissue disorders, such as Marfan syndrome and Ehlers-Danlos syndrome. It is important to note that this condition may present asymptomatically or with symptoms of heart failure as the regurgitation progresses.

In contrast, while rheumatic heart disease is a known cause of mitral regurgitation due to inflammation and scarring of the mitral valve following rheumatic fever, it is less common in industrialized nations where antibiotic prophylaxis is available. Infection, such as endocarditis, can also cause valve dysfunction, but this is typically less frequent than myxomatous degeneration. Hypertension primarily leads to left ventricular hypertrophy and may indirectly contribute to mit