Abstract 18097: Diagnostic and Prognostic Value of Serum Concentration of High-Sensitivity Cardiac Troponin T Relative to Heart-Type Fatty Acid-Binding Protein in the Early Hours of Suspected Acute Coronary Syndrome

Abstract

Background: Heart-type fatty acid-binding protein (H-FABP), a low-molecular-mass cytoplasmic protein, has been proposed as an early biomarker for acute myocardial infarction (AMI). Thus, we prospectively investigated the diagnostic and prognostic value of serum level of high-sensitivity troponin T (hsTnT) relative to H-FABP in the early hours of acute coronary syndrome (ACS). Methods: Serum samples for measurements of hsTnT and H-FABP were drawn on admission in 460 consecutive patients (median age, 67.5 yrs) hospitalized to the cardiac emergency department for suspected ACS within 6 hrs (3.5 hrs) after the onset of chest symptom. Cardiac events, which were defined as cardiac death or rehospitalization for ACS or heart failure, were monitored for 12 months after admission. The final diagnosis was adjudicated by two independent cardiologists. Results: 224 (48.7%) patients were diagnosed as AMI [ST-segment elevation myocardial infarction in 154 (33.4%) patients; and emergent coronary angiography within 24 hrs after admission in 195 (42.4%) patients]. The area under the ROC curve was higher for hsTnT than for H-FABP (Table). The sensitivity and predictive accuracy of increased hsTnT (> 0.014 ng/ml of 99th percentile) were higher than those of increased H-FABP (≥ 6.2 ng/ml of upper reference limit). Also, there was no significant difference in specificity between hsTnT and H-FABP. During 12-month follow-up period, there were 38 (8.3%) cardiac events including 11 cardiac deaths. In a stepwise Cox regression analysis, increased hsTnT (relative risk 14.5, P = 0.009), but not H-FABP, was independently associated with cardiac events. Patients with increased hsTnT had a higher risk of cardiac events within 12 months compared with those without (14.1% vs. 0.5%, P < 0.0001). Conclusion: An hsTnT assay may provide diagnostic and prognostic information superior to H-FABP assay in the early hours of suspected ACS.