SCN5A and atrial fibrillation: In summary, the functional status of critical ion channels (e.g., Nav1.5, Cav1.2, Kir2.x, hERG, KCNQ1) and the corresponding ionic currents they carry (INa, ICa,L, IK1, IKr, IKs) serve as vital indicators for evaluating electrical remodeling in AF.