IL4 and myocarditis: Studies have found that in the acute and recovery periods of theinflammatory response, many cytokines, such as interleukin-4 and transforminggrowth factor-β, can stimulate the proliferation and differentiation offibroblast, thereby causing ventricular remodeling and cardiac dysfunction [19].In our study, fibroblast activation was observed in all patients withCOVID-19-related myocarditis.