JAK2 and myocardial infarction: Janus 2 (JAK2)/STAT3 is an evolutionarily conserved signal transduction pathway that is widely involved in the regulation of inflammation, apoptosis, cell cycle, and development, and is involved in many myocardial diseases including myocardial infarction, oxidative damage, myocarditis, myocardial hypertrophy, and ventricular remodeling.