What is the most common cause of mitral stenosis?

Mitral stenosis is most commonly caused by rheumatic disease, which results from rheumatic fever—a complication of untreated streptococcal throat infections. This inflammatory condition primarily affects children and young adults, but its effects can lead to long-term heart issues, including scarring of the mitral valve. Over time, this scarring can lead to obstruction of the valve, causing mitral stenosis.

Rheumatic fever can lead to both acute and chronic valvular heart diseases, and it has historically been the predominant cause of mitral stenosis in many populations, particularly in regions where rheumatic fever is more prevalent due to issues with access to medical care.

While congenital heart disease, age-related calcification, and infective endocarditis can also lead to mitral stenosis, they are less common compared to the significant impact of rheumatic disease. Congenital heart defects are present at birth, and while they can lead to mitral stenosis, they do not account for the majority of adult cases. Age-related calcification is typically associated with aortic stenosis rather than mitral stenosis, and infective endocarditis can cause valve issues, but it is not a primary cause of chronic mitral stenosis.