Visceral Adiposity Index and Postoperative Atrial Fibrillation After Isolated On-Pump Coronary Artery Bypass Grafting

Abstract

Background:Postoperative atrial fibrillation (PoAF) remains the most common complication after coronary artery bypass grafting (CABG). The visceral adiposity index (VAI) is a composite marker of visceral adipose dysfunction and metabolic risk. This study aimed to evaluate the association between preoperative VAI and PoAF in patients undergoing isolated on-pump CABG.Methods:This retrospective, single-center cohort study included 400 consecutive patients who underwent isolated on-pump CABG between January 2019 and December 2023. VAI was calculated using sex-specific formulas that incorporated body mass index, waist circumference, triglyceride levels, and high-density lipoprotein cholesterol levels. Patients were categorized according to the median VAI value (2.87) for descriptive analyses. The primary outcome was new-onset PoAF during the index hospitalization. Multivariable logistic regression analysis was performed to identify independent predictors of PoAF. Receiver operating characteristic (ROC) analysis was used to evaluate the discriminative performance of VAI.Results:PoAF occurred in 61 patients (15.3%). Patients with VAI ≥2.87 had a significantly higher incidence of PoAF than those with VAI <2.87 (21.4% vs. 9.0%; p < 0.001). In multivariable logistic regression analysis adjusted for age, sex, left ventricular ejection fraction, and cardiopulmonary bypass duration, VAI remained independently associated with PoAF (odds ratio (OR) 1.34 per unit increase, 95% confidence interval (CI) 1.09–1.63; p = 0.005). ROC analysis demonstrated good discriminative ability of VAI for predicting PoAF (area under the curve [AUC] 0.85, 95% CI 0.79–0.90). Exploratory ROC analysis identified a VAI threshold of 3.5, corresponding to a sensitivity of 91% and a specificity of 68%.Conclusions:Higher preoperative VAI was independently associated with PoAF in patients undergoing isolated on-pump CABG. As an easily obtainable marker of visceral adiposity and metabolic dysfunction, VAI may provide complementary information for preoperative risk assessment. However, the ROC findings should be considered exploratory, and external validation is required before routine clinical application.