IL6 and rheumatic heart disease: In our study, plasma C-reactive protein level and interleukin-6 level were significantly correlated to each other, and this result can be explained by the hypotheses that following acute RF attack, there will be a continuous chronic inflammation of cardiac valves and patients with more intense inflammatory reaction have a more rapid progression of valvular dysfunction [7–9] and that C-reactive protein and interleukin-6 levels are correlated to each other and to the inflammatory process in chronic rheumatic heart disease patients [3].