Cyclophosphamide (CTX) induces myocardial fibrosis and cardiac hypertrophy, as well as changes in the expressions of several cytokines, such as interleukin (IL)-2, IL-10, IL-6, and TNF-α, which can further facilitate the occurrence and development of AF (Liu et al., 2015). Here, IL6 is linked to Myocardial fibrosis.