AF burden (10.1% [IQR 4.8%, 16.5%] vs. 6.0% [IQR 2.3%, 9.5%], <i>p</i> = 0.003), inflammatory markers (interleukin-6 [IL-6] on Day 1: 104 ± 20 vs. 98 ± 16 pg/mL, <i>p</i> < 0.001), markers of prothrombotic state (D-dimer on Day 5: 2.6 ± 0.7 mg/L FEU vs. 2.3 ± 0.7 mg/L FEU, <i>p</i> < 0.001), and postoperative hospital stay (10.7 ± 1.8 vs. 10.3 ± 1.8 days, <i>p</i> = 0.006) were significantly higher in the IR group compared to the CR group. This evidence concerns the gene IL6 and atrial fibrillation.