Here, the hub nodes, including leucine-rich repeat kinase 2 (LRRK2; degree = 38), calmodulin 1 (CALM1; degree = 25), chemokine (C-X-C motif) receptor 4 (CXCR4; degree = 25), toll-like receptor 4 (TLR4; degree = 21), catenin (cadherin-associated protein), beta 1(CTNNB1; degree = 21), and chemokine (C-X-C motif) receptor 2 (CXCR2; degree = 21) are considering as hub-genes in related to AF maintaining. The gene discussed is CXCR2; the disease is atrial fibrillation.