Background: The inflammatory prognostic index (IPI) is a novel hematological parameter that reflects both inflammatory burden and immune status. Despite several studies on this new index, the prognostic value of IPI in CABG remains unclear so far. This study aimed to evaluate whether the IPI could serve as a predictor of postoperative outcomes in patients undergoing coronary artery bypass grafting (CABG). 

Methods: A total of 640 patients who underwent isolated CABG between 2022 and 2025 were retrospectively analyzed. The optimal preoperative IPI cut-off value for predicting mortality was determined using receiver operating characteristic (ROC) curve analysis. The optimal IPI cut-off value was identified as 0.22 (AUC = 0.607; 95% CI: 0.468–0.747; p = 0.14). Based on this threshold, patients were categorized into two groups: high IPI (Group A, n = 293) and low IPI (Group B, n = 347). 

Results: Baseline demographic features, comorbid conditions, echocardiographic findings, operative variables, cardiopulmonary bypass time, cross-clamp time, and laboratory results were comparable between the groups, except for gender distribution and platelet counts. The incidence of postoperative cerebrovascular events was significantly higher in Group A. Although mortality was more frequent in Group A than in Group B (3.8% vs. 1.4%), this difference did not reach statistical significance (p = 0.06). Additionally, patients in Group A had significantly longer intensive care unit (ICU) stays (mean: 3 vs. 2.6 days, p = 0.01) and overall hospital stays (9.5 vs. 8.4 days, p = 0.002). Multivariate regression analysis demonstrated that gender, diabetes mellitus, hypertension, and IPI were not independently associated with mortality. 

Conclusions: The IPI was associated with longer ICU and hospital stays in isolated CABG patients. These results support the use of IPI as a potential prognostic index for CABG patients.