Researchers in Japan may have found a way to repair cardiac damage in patients suffering from chronic heart attack and heart failure by reprogramming cardiac fibroblasts (CFs) to cardiomyocytes (CMs) in a mouse model of chronic myocardial infarction (MI). Published online Dec. 12, 2022, in Circulation, the study showed that by tweaking the expression of a few key genes, researchers could reverse the lasting damage caused by heart attacks.