KCNE1 and atrial fibrillation: To establish the function of Kcne1 in AF inducibility in aged male mice, 2‐month‐old and 18‐month‐old mice were intravenously injected with AAV9 carrying a cTnT promoter to drive Kcne1 overexpression (AAV9‐cTnT‐Kcne1‐oe) (n = 6/group).