In the present study, we obtained a list of 1796 immune-related genes from the Immport database and intersected them with hub genes to obtain 7 hub immune-related genes, including HLA-DRA, LCK, ITK, CD48, CD3D, CD247, and IL2RG. These 7 immune-related genes were significantly elevated in DCM and AF patients compared with controls. Here, HLA-DRA is linked to atrial fibrillation.