Which valve is most commonly affected in rheumatic heart disease?

Rheumatic heart disease primarily affects the heart valves as a consequence of rheumatic fever, which is typically a complication of untreated streptococcal throat infections. The mitral valve is the most commonly involved valve in this condition. It can become stenotic (narrowed) or regurgitant (leaking), leading to heart failure symptoms and other complications.

The mitral valve is particularly susceptible because it experiences significant mechanical stress during the cardiac cycle and is subject to the immunological damage caused by the body's response to streptococcal infection. While the aortic valve can also be affected in rheumatic heart disease, the mitral valve is most frequently the primary site of disease, making it a key focus for diagnosis and management in patients with a history of rheumatic fever. Understanding this prevalence emphasizes the importance of early treatment for streptococcal infections to prevent the development of rheumatic heart disease.