Risk stratification in non-ST elevation acute coronary syndromes: predictive power of troponin I, C-reactive protein, fibrinogen and homocysteine.

INTRODUCTION

In acute coronary syndromes, myocardial damage markers and acute-phase reactants predict adverse cardiac events. The aim of this study was to define the fitted prognostic value of the most widely used variables of necrosis and inflammation as well as of homocysteine.

METHODS AND RESULTS

Troponin I, high-sensitivity C-reactive protein, fibrinogen and homocysteine were measured in 515 consecutive patients admitted to our institution for non-ST elevation acute coronary syndrome. The risk for major events (death or nonfatal myocardial infarction) through 6 months of follow-up was analysed. In the univariate analysis, all markers were related to major events (p<0.01 in all cases). In a multivariate model fitting for baseline characteristics and electrocardiographic changes, the only biomarkers related to major events were C-reactive protein >11 mg/l (2.1 [1.2-3.8] p=0.007) and troponin I >3 ng/ml (1.9 [1.1-3.4] p=0.03). Moreover, the rate of major events was significantly higher (p<0.0001) only when both C-reactive protein and troponin I were increased (31.4% vs. 9.3% if any or both markers were normal).

CONCLUSION

In non-ST elevation acute coronary syndromes elevated levels of troponin I, C-reactive protein, fibrinogen and homocysteine are strongly related to the risk of major events. The prognostic value of troponin I and C-reactive protein is independent and additive with respect to each other.