As depicted in Fig. 2b, quantitative IOD also confirmed that cTGF expression was significantly higher in EAT from the AF group (AF EAT vs. AF SAT, 50487.00 ± 30750.84 vs. 6240.7 5 ± 3001.37, P < 0.001; AF EAT vs. AF PAT, 50487.00 ± 30750.84 vs. 33461.50 ± 13565.64, P = 0.052; AF EAT vs. SR EAT, 50487.00 ± 30750.84 vs. 27277.85 ± 15141.24, P = 0.006). Here, CCN2 is linked to atrial fibrillation.