The Effect of Silymarin on the Prevention of Atrial Fibrillation After Coronary Artery Bypass Grafting.

Introduction: Postoperative atrial fibrillation is a frequent complication after coronary artery bypass grafting and is associated with increased mortality. The effects of various drugs on the occurrence of postoperative atrial fibrillation have been studied, but no one has looked into the effect of silymarin on the occurrence of postoperative atrial fibrillation.
Methods: This prospective experimental study included 160 patients undergoing coronary artery bypass grafting. The experimental group received 400 mg of silymarin orally three days before the surgery, while the control group did not. The occurrence of postoperative atrial fibrillation was monitored. Patients' clinical data and postoperative characteristics were investigated to elucidate their impact on postoperative atrial fibrillation.
Results: Postoperative atrial fibrillation occurred in significantly fewer patients in the experimental group (14 vs. 30, P=0.008). There were also lower mean values of postoperatively measured C-reactive protein (P<0.0005) and aspartate aminotransferase (P=0.001) in the experimental group. Within the multivariate regression model, a non-silymarin group (odds ratio 0.296 [0.109-0.807], P=0.005), postoperative red blood cell transfusion (odds ratio 5.218 [1.930-14.107], P=0.001), left atrial diameter (odds ratio 7.800 [2.122-28.672], P=0.002), postoperative C-reactive protein (odds ratio 1.020 [1.008-1.032], P=0.001), and CHA₂DS₂-VASc score (standing for congestive heart failure, hypertension, age ≥ 75 years [doubled], diabetes, stroke [doubled], vascular disease, age 65 to 74 years, and sex category [female]) (odds ratio 1.873 [1.279-2.743], P=0.001) proved to be independently associated with the development of postoperative atrial fibrillation.
Conclusion: This study showed that preoperative administration of silymarin significantly reduces the development of atrial fibrillation after coronary artery bypass grafting.