Abstract 2844: Heart Fatty Acid Binding Protein Improves Early Diagnosis and Risk Stratification of Acute Coronary Syndromes
Purpose: To assess if early detection of myocardial infarction (MI) would be improved by measuring heart fatty acid binding protein (hFABP), a marker of myocardial ischemia. Also, to determine if hFABP and biomarkers of inflammatory and hemostatic activity can independently predict risk of subsequent adverse events in patients with acute chest pain.
Methods: In a multicentre study, patients presenting with chest pain between Aug 03-Dec 05 were recruited prospectively. Patients were assessed on admission for clinical characteristics, ECG features, renal function, cardiac troponin T (cTnT), hFABP, inflammatory markers (white cell count (WCC), hsCRP, myeloperoxidase), and hemostatic markers (d-dimer, fibrinogen). A 12hr cTnT sample was also obtained. MI was defined as elevated cTnT (>0.03mcg/L). McNemar’s test was used to compare sensitivities. Patients recruited in the first year of the study were followed up for 1 year for the subsequent incidence of death and MI. The independent predictive value of abnormal clinical/ECG features and elevated biomarkers (including cTnT) for death or MI within 1year was determined using logistic regression analysis.
Results: MI was confirmed in 223 of the 420 patients recruited who had complete blood data available. Of the 128 patients who presented within 3 hours of symptom onset 69 had MI. For these patients the sensitivity of hFABP >5 mcg/L for MI was 70%, significantly higher than for initial cTnT (45%, p<0.002): the specificity of hFABP was 63%. For patients presenting after 3 hours sensitivities were not significantly different. One year follow-up data were available in 233 of the 252 patients recruited during the first year. Death/MI occurred in 30/233 (13%). The only independent predictors of death/MI were hFABP >5 mcg/L (p=0.016), WCC >12,100/microL (p=0.027), and creatinine >120 micromol/L (p<0.001).
Conclusions: Sensitivity of hFABP within the first 3 hours is superior to cTnT for detection of MI. Additionally, hFABP has significant independent value for prediction of recurrent adverse events; hsCRP, myeloperoxidase, fibrinogen, and d-dimer have not.