Multi-inflammatory index as a novel predictor of new-onset atrial fibrillation after off-pump coronary artery bypass grafting

Background: To our knowledge, a possible predictive relationship of the multi-inflammatory index (MII) with new-onset atrial fibrillation (AF) after off-pump coronary artery bypass grafting (CABG) has not yet been studied in the literature. Aims: We aimed to investigate whether the MII is a novel group of hematological markers for predicting postoperative new-onset AF in patients undergoing off-pump CABG. Methods: A total of 427 patients undergoing isolated off-pump CABG between October 2021 and December 2023 were enrolled in this retrospective observational cohort study and allocated to two groups: the AF group (n = 108) and the non-AF group (n = 319). The groups were compared in terms of baseline clinical patient characteristics, laboratory parameters, and operative and postoperative data. Results: The median values of age, length of hospital stay, platelet and neutrophil count, C-reactive protein level, systemic immune-inflammation index, MII-1, MII-2, and MII-3 were significantly greater in the AF group compared to the non-AF group in univariate analyses. In multiple explanatory variable logistic regression analysis, MII-1, MII-2, and MII-3 were determined to be significant hematological variables, and thereby these indices were considered the independent predictors of postoperative new-onset AF. Receiver operating characteristic curve analyses showed that to predict postopera - tive new-onset AF, MII-1 of 22.47 constituted the cut-off value with 62.0% sensitivity and 57.0% specificity, MII-2 of 141.77 constituted the cut-off value with 43.5% sensitivity and 76.8% specificity, and MII-3 of 5669 constituted the cut-off value with 63.8% sensitivity and 58.3% specificity. Conclusion: This study demonstrated for the first time that all MIIs predicted new-onset AF after off-pump CABG.