Abstract 12590: A Multi-center Comparison of Established and Emerging Cardiac Biomarkers for the Diagnostic Evaluation of Chest Pain in the Emergency Department.
Introduction: Prompt and accurate diagnostic evaluation of chest pain patients in the Emergency Department (ED) remains a challenge. We evaluated an array of established and emerging cardiac biomarkers for acute coronary syndrome (ACS) among patients with chest discomfort.
Methods: Among patients presenting to the ED with symptoms suggestive of ACS, we compared first-draw results of cardiac troponin (cTnT), amino-terminal pro-B type natriuretic peptide (NT-proBNP), ischemia modified albumin (IMA; Inverness Medical Innovations), heart fatty acid binding protein (H-FABP; Hycult Technologies), high sensitivity troponin (hsTnI; Singulex, Inc) and free fatty acids (FFA; FFA Sciences). The value of each marker for ACS diagnosis/exclusion was determined using C-statistic, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) analyses.
Results: 318 patients (mean age = 58 years; 53% male) were studied; 62 (19.5%) had a final diagnosis of ACS, of whom 40 had unstable angina. Neither IMA nor H-FABP detected or excluded ACS. A statistically significant increase in the cTnT C-statistic of 0.60 was seen with the addition of NT-proBNP (change = 0.09; P =.001), hsTnI (change = 0.13; P <.001), and FFA (change = 0.15; P <.001). NT-proBNP had 73% sensitivity, 54% specificity and 90% negative predictive value (NPV) for ACS; hsTnI had 57% sensitivity, 86% specificity, and 81% NPV, while FFA had 75% sensitivity, 72% specificity, and 92% NPV. In IDI and NRI analyses, NT-proBNP, hsTnI and FFA all added significant reclassification information beyond cTnT (Table). Changing the gold standard to hsTnI, FFA still added significant reclassification for both events and non-events (Table).
Conclusions: Among ED patients with symptoms suggestive of ACS, results for NT-proBNP, hsTnI or FFA added diagnostic information to cTnT. In the context of hsTnI results, FFA measurement significantly reclassified both false negatives and false positives.
- © 2010 by American Heart Association, Inc.