Abstract 15134: Calcium-Modulated Protein S100a8/a9: Novel And Sensitive Biomarker for Early Diagnosis of Acute Coronary Syndromes
Plaque instability and rupture leads to coronary thrombosis, the pathophysiologic substrate of acute coronary syndromes (ACS). Transcriptional profiling studies in patients with ACS identified the calcium-modulated protein S100A8/A9 as potential predictor of myocardial infarction. S100A8/A9 broadly regulates vascular inflammation and contributes to vascular injury. In order to establish a role for S100A8/A9 for coronary atherosclerotic plaque rupture, we measured plasma concentration of S100A8/A9 from samples simultaneously obtained from the aorta (Ao) and the coronary venous sinus (CVS) in patients with stable CAD (n=30) and with ACS (n=26). In patients with ACS, circulating levels of S100A8/A9 were significantly elevated in both the aorta (p=0.038) and the CVS (p=0.037). Most importantly, detailed analysis of the temporal release kinetics into the coronary circulation revealed that S100A8/A9 levels were significantly increased in the CVS of ACS patients presenting within 3h from symptom onset compared to stable CAD (p=0.001). This resulted in a significant positive transcoronary concentration gradient ([CVS]>[Ao], p=0.014) for S100A8/A9, indicating a coronary release into the systemic circulation. Of note, elevated levels of S100A8/A9 were already measurable in patients (n=3) presenting within 2h after symptom onset despite no elevation of hsTroponin T (hsTNT), yet. Consistently, diagnostic performance, by ROC curve analysis, of S100A8/A9 concentration was excellent for early diagnosis of ACS (AUC=0.834, p=0.001), as compared to hsTNT (AUC=0.751, p=0.012). In conclusion, S100A8/A9 may represent a promising, novel and sensitive marker for early diagnosis of ACS.
- © 2011 by American Heart Association, Inc.