How often does troponin elevation identify acute myocardial infarction in the emergency department?
Jain T, Nowak R, Hudson M, Moyer M, Jacobsen G, McCord J. How often does troponin elevation identify acute myocardial infarction in the emergency department? J Am Coll Cardiol. Mar 2017;69(11):1191-1191.
J Am Coll Cardiol
Background: Cardiac troponin (cTnI) is used broadly in a heterogeneous population evaluated for possible acutemyocardial infarction (AMI) in the emergency department(ED). We sought to determine how often cTnI elevation, at various levels, was associated with the diagnosis of AMI. Methods: In a single-center we prospectively enrolled 569 patients evaluated for possible AMI in the ED from May 2013 to April 2015. Diagnosis of AMI was adjudicated by 2 independent physicians in accordance with the universal definition of AMI using all available clinical information over 30 days and serial cTnI measurements, with cTnI > 0.04 ng/ml (Siemens Ultra-cTnI) considered positive. Patients requiring immediate reperfusion were excluded. Thehighest measured cTnI was divided into interquartile ranges. Results: Of the 569 patients, 116 (20%) had a cTnI > 0.04 ng/ml. Of those with elevated cTnI 45 patients (39%) were diagnosed with AMI. Patients with low-level cTnI were unlikely to be diagnosed with AMI and the incidence of AMI increased with higher cTnI levels (p<0.001). Conclusions: The majority of patients with low-level cTnI above therecommended 99th percentile are not diagnosed with AMI in the ED. The incidence of AMI increases with higher cTnI values. (Figure Presented).