In summary, our study suggested that miR-27a-3p/Hoxa10/Kv4.3 axis regulated myocardial hypertrophy and electrical remodeling caused by Ang II, thus providing new therapeutic strategies for myocardial hypertrophy and arrhythmias clinically, as well as opening up new fields and expanding new horizons for researchers. The gene discussed is KCND3; the disease is cardiac hypertrophy.