Pericardial Fluid Cardiac Troponin I Predicts Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting

This prospective cohort study evaluated whether cardiac troponin I measured in pericardial drainage fluid (PCF-cTnI) enhances risk stratification for postoperative atrial fibrillation (POAF) following coronary artery bypass grafting (CABG). In an analysis of 114 patients, investigators measured peripheral and PCF-cTnI at six hours postoperatively to develop a predictive model and a simplified clinical tool, the CALT score. POAF occurred in 30.7 percent of patients. Postoperative six-hour PCF-cTnI was noted to be an independent predictor of POAF (OR = 5.502, p= 0.002) and demonstrated good discrimination (AUC = 0.821), with favorable calibration and clinical utility. The authors discuss that localized myocardial troponin release into the pericardial space, which was found to be 39-fold higher than in serum, is related to an inflammatory cascade that alters epicardial electrophysiology. The authors conclude that integrating PCF-cTnI into the CALT score effectively captures structural atrial vulnerability and localized injury.