Abstract 1792: Multiple Biomarker Utilization for Detection of Myocardial Infarction Based on Presentation Sample in Patients with Symptoms Suggestive of Acute Coronary Syndrome

OBJECTIVES: To determine if multiple biomarkers representative of numerous pathophysiologic pathways increase diagnostic accuracy for early detection of myocardial infarction (MI) in patients presenting with symptoms of acute coronary syndrome (ACS). BACKGROUND: Cardiac troponin has been accepted as the preferred biomarker for detecting myocardial injury and acute myocardial infarction. METHODS: Seven biomarkers (myeloperoxidase (MPO), soluble CD40 ligand (CD40L), placental growth factor (PIGF), metalloproteinase-9 (MMP-9), high sensitive C-reactive protein (hsCRP), cardiac troponin I (cTnI), N-terminal pro-B-type natriuretic peptide (NT-proBNP)) were measured on admission plasma specimens and estimated glomerular filtration rate (eGFR) calculated in 457 patients presenting with symptoms suggestive of ACS. Median time from symptom onset to presentation was 3.1 hours. Twenty-five (5.4%) patients were diagnosed with acute MI (ICD 410.×1 code). Clinical sensitivities and specificities of each biomarker for AMI were determined based on 99 th percentile reference values. Forward and backward stepwise logistic regression modeling techniques were used to identify biomarkers independently predictive of AMI. RESULTS: Clinical sensitivity of the biomarkers ranged from 20% to 96% with specificity ranging from 19% to 89%. Highest clinical sensitivity was MMP-9 but specificity was only 19%. cTnI demonstrated a clinical sensitivity of 72% and specificity of 89% with false negatives occurring in 7 patients and false positives in 49. In multivariate models, cTnI (p < 0.001) and either hsCRP (p = 0.009) or MMP-9 (p = 0.03) and cTnI were independently predictive of AMI. hsCRP or MMP-9 increased specificity to 95% or 94% respectively but reduced sensitivity to 56% and 68% respectively relative to cTnI alone. CONCLUSION: Our findings support utilization of cTnI alone, rather than a multi-biomarker approach, when using an analytically robust assay based on the 99 th percentile reference value decision cutoff, as the most clinically accurate biomarker for the early diagnosis of AMI.