Objective:To investigate whether preoperative serum soluble receptor activator of nuclear factor-кB ligand(sRANKL),osteoprotegerin(OPG),and sRANKL/OPG ratio are associated with the stabilization of restored sinus rhythm(SR) in persistent atrial fibrillation(AF) patients after valve surgery with concomitant modified maze procedure. Methods:We enrolled 114 patients with persistent AF who restored SR after valve surgery with concomitant modified maze procedure. According to the clinical follow-up outcomes at the third months after surgery,all the patients were divided into the AF recurrence group and the non recurrence group, respectively. Preoperative radial artery blood samples were obtained for measurement of serum sRANKL and OPG by ELISA. Results:Preoperative serum levels of sRANKL,OPG and sRANKL/OPG ratio were significantly higher in the AF recurrence group than those in the group with no AF recurrence. In multivariate Logistic regression analysis, except left atrial diameter,preoperative serum sRANKL level and sRANKL/OPG ratio independently predicted AF recurrence. According to ROC curve analysis,the best diagnostic values of serum sRANKL level and sRANKL/OPG ratio for predicting AF recurrence were 6.75 pmol/L and 0.87,respectively. The sensitivity,specificity, and accuracy of the recurrence predicted by sRANKL(>6.75 pmol/L)were 89.7%,89.3% and 89.5%,respectively,and those by the sRANKL/OPG ratio(>0.87)were 92.3%,98.7% and 92.1%,respectively. Conclusion:These findings suggest that preoperative serum sRANKL level and sRANKL/OPG ratio independently predict the recurrence of AF after valve surgery with concomitant modified maze procedure. Therefore,it can be used to screen patients who are suitable for the modified maze procedure or to be used as the target of early intervention to reduce the recurrence of AF.