The prognostic value of postoperative cardiac troponin I and T for major adverse cardiac events after coronary artery bypass grafting: a systematic review

Background

This systematic review describes the prognostic value of postoperative cardiac high-sensitive troponin I and T as risk markers for major adverse cardiac events (MACE) after coronary artery bypass graft (CABG) surgery and their predictive performance.

Methods

PubMed and Embase were searched up to 14 October 2024. Studies were included if they reported either the association between cardiac troponin I and T and MACE (using risk-, hazard-, or odds ratios) or the accuracy of troponin I and T based prediction models for MACE (using c-statistics and calibration) within 72 h after CABG. MACE was defined as the composite of myocardial infarction, coronary artery revascularisation, cardiac death, non-fatal cardiac arrest, and heart failure. Risk of bias was assessed using the Quality in Prognostic Studies tool.

Results

Out of 2273 studies, 10 studies were included. Five studies reported on troponin I (1956 patients) and five on troponin T (5615 patients). MACE composites were heterogenous, with only two studies using an identical composite. Increased postoperative troponin I and T concentrations were associated with higher risk of MACE, with a hazard ratio range of 1.6–11.1 for troponin I (n=2) and an odds ratio range of 0.9–67.9 for troponin T (n=5). Discriminative performance was moderate to good for troponin I (n=3, c-statistics range 0.60–0.81) and moderate for troponin T (n=3, c-statistics range 0.72–0.77). No studies reported calibration for troponin I. For troponin T (n=1) calibration was good for in-hospital MACE (Hosmer–Lemeshow P=0.20). Risk of bias was moderate to high across domains.

Conclusions

Postoperative cardiac troponin I and T biomarkers are associated with postoperative MACE after CABG. The current evidence on the predictive value for postoperative MACE is insufficient to use troponin I and T for risk stratification.