This document discusses rheumatic heart disease, defining it as a post-streptococcal inflammatory disease affecting the heart, joints, nervous system and skin. It most commonly affects children ages 5-15. The disease is more common in low socioeconomic groups and causes damage through lesions in the heart tissue known as Aschoff nodules. These nodules progress through exudative, proliferative and fibrotic stages, ultimately causing scarring of the heart valves and tissues if left untreated. The mitral valve is most often affected, followed by the aortic valve.