The results demonstrated that CTGF protein levels were positively correlated with LAD (immunofluorescence: r = 0.862, P = 0.030, Western blot: r = 0.740, P = 0.045) and the duration of AF episodes (immunofluorescence: r = 0.766, P = 0.045, Western blot: r = 0.806, P = 0.025). The gene discussed is CCN2; the disease is atrial fibrillation.