Introduction
Mitral valve disease affected approximately 5.8 million adults in the United States in 2016, with 5.49 million suffering from mitral regurgitation and 323 127 suffering from mitral stenosis. Mitral valve disease is prevalent across all age groups; however, it increases with age and affects 5.1% of elderly aged 65 and above.1-3The mitral valve has the most complex anatomy out of the four valves of the heart. It is also the valve most frequently causing disease. The three most common diseases of the mitral valve include mitral stenosis, mitral regurgitation, and mitral valve collapse.4 Out of these, mitral regurgitation (MR) is by far the most frequently diagnosed and accounts for approximately 9.3% of over 75-year old, whereas mitral stenosis accounts for around 0.2%.5
Mitral regurgitation consists of two types: primary and secondary. Primary MR is a pathology of the mitral valve apparatus whereas secondary MR is a pathology of the left atrium or ventricle that ultimately affects the function of the mitral valve. Secondary MR can be further classified into ischemic or non-ischemic, depending on the cause, which will require different treatment plans.6 Common causes of MR include annular calcification in the elderly, rheumatic fever, infective endocarditis, and left ventricular dilatation in functional mitral regurgitation. On the other hand, typical causes of mitral stenosis include rheumatic fever and congenital causes.7 In order to treat mitral valve diseases, a surgical attempt is the golden standard and aims to either restore function or to replace the valve. Where surgery is contraindicated, the transcatheter approach has proved to be a reliable option, especially for secondary mitral regurgitation.8,9