Work

Pericardial fluid cardiac troponin I predicts postoperative atrial fibrillation after coronary artery bypass grafting

Year: 2026

Type: article

Abstract: Objective Cardiac troponin I (cTnI) is a sensitive biomarker of myocardial injury. We hypothesized that cTnI measured in pericardial drainage fluid (PCF), which reflects the cardiac microenvironment, may enhance risk stratification for postoperative atrial fibrillation (POAF) after coronary artery bypass grafting. Methods In this prospective cohort study, 114 patients undergoing elective coronary artery bypass grafting were enrolled. The primary end point was new-onset POAF within 7 days postoperatively. Blood and PCF cTnI at 6 hours postoperatively were measured. Variables were screened using least absolute shrinkage and selection operator regression and were then incorporated into multivariable logistic regression to construct a predictive model. A simplified risk score (CALT score) was developed. Model performance was compared with existing POAF tools, including the POAF score, CHA 2 DS 2 -VASc, and the atrial fibrillation risk index. Results POAF occurred in 30.7% of the cohort. Postoperative 6-hour PCF-cTnI was an independent predictor of POAF (odds ratio, 5.502; 95% CI, 1.887-16.045; P = .002) and significantly enhanced continuous net reclassification improvement (0.562; 95% CI, 0.189-0.921; P = .002). The CALT score comprised left circumflex artery lesions, left atrial diameter, left ventricular end-diastolic diameter, postoperative 0-hour serum calcium, and postoperative 6-hour PCF-cTnI. The PCF-cTnI–based model demonstrated good discrimination (area under the receiver operating characteristic curve=0.821), with favorable calibration and clinical utility. Compared with commonly used risk scores, the CALT score exhibited superior discrimination and calibration. Conclusions This study provides novel evidence that PCF-cTnI is a strong predictor of POAF. The CALT score, integrating PCF-cTnI with clinical factors, provided superior predictive performance by capturing both the vulnerable atrial substrate and localized myocardial injury.

Source: JTCVS Open

DOI: 10.1016/j.xjon.2026.101954