CXCR4 and atrial fibrillation: As shown in Figure S9, the relative expression levels of CXCR4, SNAI2, S100A4, IGFBP3, CSNK2A1, CHGB, VCAN, APOE, C1QC and TYROBP were significantly higher in the AF group compared with the control group, according to the PCR results (p < 0.05, Figure S9).