Rheumatic fever (RF) and rheumatic heart disease (RHD) remain highly prevalent, affecting approximately 40 million people, mostly in low- and middle-income countries, but also in select marginalized populations in higher-income countries.^, Brazilian data regarding RF prevalence is scarce mainly due to (a) difficulties in acute RF diagnosis, (b) cost of RHD screening and (c) the fact that reported data on surgery or death may represent RF incidence from 2 decades ago. The most feared consequence of RF is valvular heart disease, which leads to a worsening in the quality of life, hospitalizations and need for surgical procedure, primarily in young people.^, Therefore, there is an urgent need to better understand the factors that influence valvular heart disease (VHD) progression. In this context, Gomes et al. studied the histopathological changes in mitral valves of patients with RHD undergoing mitral valve replacement.

Inflammation in one of the key components of VHD in patients with RF. In the acute stage of infection, the histopathological findings are the presence of dense valvular inflammatory infiltrates and Aschoff nodules, characterized as collagen fibrinoid degeneration surrounded by lymphocytes, macrophages, giant cells, plasma cells, and palisades of fibroblasts.^– Chronic RHD usually presents with cuspid calcification, fibrosis and commissural fusion. However, the role of inflammation in chronic VHD is still under study.

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