Using the SYNTAX score to predict myocardial injury early after on-pump coronary artery bypass surgery: a single-centre experience analysis

INTRODUCTION: Marked isolated elevation of cardiac biomarkers (CK-MB, cardiac troponin I, heart-type fatty acid binding protein, hFABP) within 48 hours after coronary artery bypass surgery (CABG), even in the absence of electrocardiographic/angiographic evidence of myocardial infarction (MI), indicates prognostically significant cardiac procedural myocardial injury. There are no data exploring the relationship between the complexity of coronary atherosclerotic burden and early post-CABG myocardial injury. AIM: To analyse correlations and predictive strength of the SYNTAX score (SS) for early myocardial injury after on-pump CABG. MATERIAL AND METHODS: One hundred and twenty consecutive patients undergoing CABG were included in the analysis. We obtained data on demographics, medical history, cardiovascular risk factors and echocardiography. Cardiac biomarkers were assessed at 6 hours after CABG. Multivariate linear regression analysis was performed to evaluate independent variables correlated with cardiac biomarkers. RESULTS: The most significant predictor for myocardial injury was SS, strongly correlated with the rise of all cardiac biomarkers (p < 0.001). Hypertension and creatinine clearance were associated with cTnI and hFABP. Diabetes was corelated with hFABP. In a multivariate analysis including all significant predictors, SS remained an independent predictor for myocardial injury, strongly associated with hFABP (p < 0.001, OR = 5.79, 95% CI: 3.59–7.98), cTnI (p < 0.001, OR = 6.49, 95% CI: 4.78–8.20), but not with CK-MB (95% CI: 0.61–1.07). CONCLUSIONS: Defining myocardial injury as elevation of cardiac biomarkers between normal values and the cut-off for MI has a tremendous clinical significance as patients maintain high negative prognostic rates. SS could be used to predict post-operative rise of cardiac biomarkers, the correlation between SS and myocardial injury being very solid.