We sought to evaluate the added value of heart fatty acid protein assay (HFABP) for rapid diagnosis of acute myocardial infarction in a prospective cohort of emergency department (ED) patients with acute chest pain.

High-sensitivity cardiac troponin T (hs-cTnT; Roche Diagnostics, Meylan, France) and HFABP (Randox, Mauguio, France) were blindly assayed from venous blood samples obtained at admission. Diagnosis was made by 2 ED physicians using all available data and serial cardiac troponin I as the biochemical standard. Diagnostic performances of HFABP combined with hs-cTnT were assessed using logistic regression. Analysis was conducted in all patients and in patients without ST-elevation myocardial infarction.

A total of 181 patients were included (age, 61 ±17 years; male sex, 66%). Acute myocardial infarction occurred in 47 (25.9%) patients, including non–ST-elevation myocardial infarction in 31 (17.1%). The receiver operating characteristic area under the curve was 0.893 for hs-cTnT levels at presentation (95% confidence interval, 0.812-0.974) and 0.908 (95% confidence interval, 0.839-0.977) for the combination of hs-cTnT and HFABP, with no significant (P=.07). Adding HFABP to hs-cTnT increased both sensitivity and negative predictive value (NPV) for non–ST-elevation myocardial infarction diagnosis, with about 13% and 3% increase, respectively, leading to a sensitivity of 97% and an NPV of 99%.

The assessment of HFABP at ED admission adds incremental value to initial hs-cTnT. The increase of sensitivity and NPV without sacrificing the specificity and positive predictive value in patients with chest pain with noncontributive electrocardiogram could potentially allow safe and early rule out of acute myocardial infarction without the need for further serial troponin testing.