BackgroundCarbohydrate antigen 125 (CA125) is a biomarker often used in diagnosis of ovarian tumors. Studies also show that elevated CA125 implicates worse outcomes among patients with heart failure, while latter of which plays an important role in the pathophysiology of left ventricular aneurysm (LVA). However, the prognostic value of CA125 in LVA patients undergoing surgical left ventricular reconstruction (SLVR) remains unclear. MethodsIn this single-centered cohort study, a total of 309 patients with LVA undergoing SLVR were retrospectively recruited. Univariable regression analysis was performed to identify the potential confounders for each outcome, followed by multivariable adjustment to confirm the association between CA125 and outcomes. The primary outcome was the overall mortality, and the secondary outcome was the major adverse cardiovascular and cerebrovascular events (MACCE) and perioperative outcomes. A receiver operating characteristic (ROC) curve was use to find the optimal cut-off value of CA125. ResultsThe median follow-up time was 55 months. The cohort was predominantly male (86.4%), with an average age of 58.6 years. Log (CA125) was associated with overall mortality (hazard ratio [HR]: 2.15, 95% confidence interval [CI]: 1.06–4.36, P = 0.033), prolonged hospital-stay time (HR:1.07, 95%CI: 1.03–1.12, P = 0.001) and increased risk of postoperative ventricular support (HR: 2.81, 95%CI: 1.10–7.18, P = 0.031) after multivariate adjustment. The optimal cut-off value for the CA125 for all-cause mortality was 13.825 U/ml with the area under curve of 0.675. ConclusionElevated-CA125 implicates poorer short- and long-term prognosis in LVA patients undergoing SLVR.