Ana Rebeca Jaloma-Cruz

Background/Objectives: Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery with cardiopulmonary bypass (CPB), increasing morbidity and prolonging hospitalization. This study aimed to develop and validate an exploratory prediction model that integrates perioperative inflammatory biomarkers with clinical and surgical variables to identify patients at risk of early POAF. Methods: A prospective exploratory cohort of 89 patients undergoing coronary artery bypass grafting (CABG; n = 36), valve surgery (n = 40), or CABG–valve surgery (n = 13) was evaluated. Clinical, surgical, and proinflammatory serum biomarkers (IL-6, IL-8, IL-10, and CRP) were recorded preoperatively (T1) and at 24 h (T2) and 48 h (T3) postoperatively. Multiple-comparison adjustments were made using the Benjamini–Hochberg false discovery rate. Predictor selection was based on bootstrap-derived stability using LASSO-penalized logistic regression, and the final model was estimated using Firth’s bias-reduced logistic regression. Results: POAF incidence was 8.3% in CABG, in contrast to 22.5% and 30.8% in valve and CABG-valve surgeries, respectively. After multiple-comparison corrections, only IL-6 at T2 postoperatively was significantly higher in patients who subsequently developed POAF. Bootstrap-based stability selection retained T2 postoperative IL-10 and magnesium concentrations in the final model, which achieved an apparent AUC of 0.776 and a bootstrap optimism-corrected AUC of 0.728, with acceptable calibration (Brier score = 0.103), negligible multicollinearity (VIF = 1.04), and a negative predictive value of 95.5% at the optimal Youden threshold. Conclusions: Our findings support an exploratory prediction model with moderate discrimination for POAF after cardiac surgery with CPB, providing a methodological foundation for future multicenter validation studies.

Patients with cardiovascular diseases often require cardiac surgery with cardiopulmonary bypass (CPB), which triggers inflammation and increases the risk of postoperative atrial fibrillation (POAF). This study assessed the predictive value of inflammatory biomarkers and clinical and surgical variables for POAF in patients undergoing coronary artery by-pass grafting (CABG; n = 36), valve surgery (n = 40), or combined CABG and valve surgery (n = 13), all of whom utilized CPB. Levels of IL-6, IL-8, IL-10, and C-reactive protein (CRP) were measured preoperatively, at 24 and 48 hours postoperatively, and at discharge. Sta-tistical analyses included t-tests, Mann–Whitney U tests, correlation analysis, logistic regression, and receiver operating characteristic (ROC) curve analysis. Sixteen of 89 patients (18%) developed POAF between 48 and 72 hours after surgery. The Society of Thoracic Surgeons (STS) score and hemoglobin at 24 hours were significantly different (p < 0.05) between the POAF and non-POAF groups. At 24 hours, POAF patients had significantly higher IL-6, IL-8, and IL-10 levels (p < 0.02); IL-6 remained elevated at 48 hours (p < 0.05), while CRP declined at discharge (p = 0.05). A multivariable model including STS score, IL-6 at 24 hours, and postoperative magnesium yielded an AUC of 0.82, with an optimism-corrected AUC of 0.77 after internal bootstrap validation. Integrating inflammatory and clinical variables produced a robust predictive model.