Rheumatic heart disease
Following the initial attack, ARF can be reactivated by subsequent exposure to GAS. The development of rheumatic heart disease (RHD) may occur over years or even decades, as recurrent inflammation of the endocardium, and especially the heart valves, leads to increased fibrosis and scarring. The valves of the heart become permanently thickened and retracted, and leaflets (flaps of the heart valves) may adhere to each other. This stenosis of the valves causes dysfunction, with regurgitation and reduced opening.