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