In RHD, heart valve lesions are formed which are mediated by autoimmune reaction between streptococcal antigens (M protein and group A carbohydrate epitope GlcNAc) and heart tissues.
Rheumatic heart disease (RHD) is considered to be an autoimmune disorder mediated by group A streptococcal (GAS) M protein-specific T cells and antibodies that cross-react with cardiac antigens and epitopes of the GAS M protein.