MANF and atrial fibrillation: Our previous studies have demonstrated a positive role of MANF in cardiocyte protection, as well as the increased MANF level in atrial fibrillation and bacterial myocarditis.[22, 23] To further explore the protective effect of MANF on myocardial cells, we focused on the change and function of myocardial cell‐derived MANF in the MH pathological process.