SCN8A and atrial fibrillation: Therefore, the predicted AF models of Nav1.2 and Nav1.6 were superimposed onto the cryo-EM structure of Nav1.2 (PDB ID: 6J8E) for the Cα atoms belonging to the transmembrane (TM) α helices (aa 1-1777), achieving backbone RMSD values of 0.899 Å and 0.744 Å, respectively.