ObjectivesThe present study aimed to evaluate the prognostic value of preoperative carbohydrate antigen 125 (CA125) levels for clinical outcomes after off-pump coronary artery bypass grafting (OPCAB).MethodsA total of 314 consecutive patients who underwent OPCAB were enrolled in this study and divided into three groups corresponding to baseline CA125 level tertiles. Clinical outcomes of these patients were followed up after 1 year. The primary endpoint was the incidence of combined major adverse cardiac events (MACE).ResultsEvent-free survival was significantly associated with the CA125 tertile (log-rank P=0.021); specifically, hazard ratios (HRs) increased progressively from CA125 tertile 1 to tertile 3 [vs. tertile 1: tertile 2h=1.8; 95% confidence interval (CI): 1.1-2.8, P=0.040; tertile 3h=2.9; 95% CI: 1.1-8.1, P=0.018]. In the first multivariate Cox regression analytical model (all variables except EuroSCORE), CA125 was an independent predictor of MACE (HR=1.1, 95% CI: 1.0-2.4, P=0.016). In a second model (CA125 levels and EuroSCORE only), CA125 remained an independent predictor of MACE (HR=1.1, 95% CI: 1.0-1.3, P=0.036).ConclusionAn increased preoperative CA125 level is an independent predictor of worse clinical outcomes after OPCAB during a 1-year follow-up.