Prognostic value of the new high sensitive cardiac troponin T assay (hs-cTnT) after coronary artery bypass grafting

Abstract

Background The aim of the study was to assess the value of post-operative cardiac troponin T-levels, measured with a new highly sensitive assay (hs-cTnT), as a suitable parameter to predict patients' outcome after cardiac surgery. With the introduction of the new hs-cTnT assay the correlation between measured levels and the post-operative patient's outcome remains to be evaluated. Methods Patients undergoing coronary artery bypass grafting (n = 213) were included. Perioperative measurements of hs-cTnT and CK-MB were correlated to parameters of clinical outcome and further explored. Patients with an uneventful course were compared with those with post-operative complications, including need of repeat revascularization (RR) or death (RR/death), cardiogenic shock (CS) or death (CS/death) and a combination of all (RR/CS/death). Results Significant results were observed in patients after isolated CABG, where CS/death and RR/CS/death patients had higher post-operative hs-cTnT levels (P < 0.01). Moreover, multivariate analysis of the CABG-group revealed that acute renal failure (OR =14.7, 95% CI =2.7-79.1, P < 0.001), early post-operative hs-cTnT levels higher than the upper quintile (> 1,476.8 pg/ml) (OR =8.1, 95% CI =3.0-22.2, P < 0.001) and unstable angina pectoris (OR =2.4, 95% CI =1.1-5.7, P < 0.05) were the most powerful independent predictors of post-operative complications. Upon discriminant analysis the application of hs-cTnT almost doubled the sensitivity of the outcome prediction. Conclusions The new hs-cTnT assay is a useful diagnostic tool that may significantly enhance the prediction of adverse events after CABG. In our study a hs-cTnT-value >1,476.8 pg/ml proved to be a reliable marker for ongoing post-operative complications.

Keywords: High sensitive troponin; cardiac surgery; coronary artery bypass grafting.