Diffuse non-specific myocarditis with Aschoff bodies.(c) Endocardium --* Small way projections, i.e. verucae along the line of closure on the valvular leaflets (especially on left side mitral valve).2. Chronic rheumatic carditiso Chronic RHD is chracterized by organization of the acute inflammation and subsequent fibrosis. o In paicular, the valvular leaflets becomes involved and characterized by -ra Leaflet thickening Commissural fusion Shoening, thickning and fusion of chordae tendinae.o Fibrous bridging across the valvular commissures and calcification create "fish moutn" or "Buttonhole"stenosis. o Mitral valve is involved most commonly.o RHD is the most common cause of mitral stenosis.o Aoic valve is second commonest valve to involve.o Tricuspid valve may also be involved.o Irrigular thickening of the posterior wall of left atrium --> MacCallum plaque.o MacCallum plaque is due to subendothelial collection of Aschoff nodules.">