Cardiac troponin I (cTnI) is a highly sensitive and specific marker for myocardial damage, which has been shown to predict patients outcome pre- and postoperatively following elective coronary artery bypass surgery (CABG). Wether preoperatively elevated cTnI levels similarily predict the outcome in patients undergoing emergency CABG due to acute coronary syndromes (ACS) is currently unknown.
A possible correlation between preoperative cTnI levels and in-hospital mortality and major adverse cardiac events (MACE) were investigated in 57 patients with ST-elevation ACS (STE-ACS) in group 1 and 197 with Non-ST-elevation ACS (NSTE-ACS) in group 2 with 12 hours between onset of symptoms and revascularization. Primary study endpoint was all-cause in-hospital mortality. Secondary endpoints were low cardiac output syndrome (LCOS) and hospital course.
CTnI levels on admission were significantly higher in group 1 compared to group 2 (7.1±1.8 vs. 1.4±1.8 ng/mL; P<0.001). LCOS with subsequent IABP-support occurred in 16/57 (28.1%), and 18/197 (9.1%) patients, respectively (Odds ratio [OR]: 3.9, 95% confidence interval [CI]: 1.7-8.8; P<0.001). Overall in-hospital mortality was significantly higher in group 1 compared to group 2 (14.3 vs. 4.1%; OR: 3.9, 95% CI: 1.3-12.3; P<0.01). Postoperative ventilation time, intensive care and hospital stay were significantly longer in group 1 compared to group 2. Univariate and multivariate logistic regression analyses of preoperative cTnI levels strongly correlated with in-hospital mortality and LCOS in patients with STE-ACS (P<0.01) and NSTE-ACS (P<0.001).
Preoperative cTnI measurement before emergency CABG appears as a powerful and independent determinant of short-term surgical risk like in-hospital mortality and MACE in STE-ACS and NSTE-ACS.
Preoperative cTnI measurement in patients undergoing emergency CABG due to STE-ACS or NSTE-ACS can serve as an incremental variable of risk for in-hospital mortality and MACE. Whether the time point for surgery should be postponed or rather accelerated due to the information of a single preoperative cTnI level remains uncertain and has to be elucidated in further studies.
Matthias Thielmann, None.