73 Early Exclusion of Major Adverse Cardiac Events in Emergency Department Chest Pain Patients: Prospective Observational Study

Abstract

The current evaluation of chest pain patients presenting to an emergency department (ED) with suspected acute coronary syndrome (ACS) is a lengthy process involving serial measurements of troponin. We aimed to validate the diagnostic accuracy of combinations of the Thrombolysis in Myocardial Infarction (TIMI) score with a single high-sensitivity cardiac troponin T (hs-cTnT) assay within 2 hours of ED arrival for the early rule-out of 30-day major adverse cardiac events (MACE), and to compare the TIMI score with combinations of heart-type fatty acid binding protein (H-FABP) and a modified HEART score. 602 consecutive adult patients with chest pain (ST-elevation myocardial infarction was excluded) and suspected ACS were recruited with TIMI and HEART scores, and point-of-care H-FABP test performed. MACE occurred in 42 (7.0%) patients within 30 days. A modified TIMI score of zero alone identified 65 (11%) patients, and a HEART score ≤2 identified 96 (16%) patients, as having low risk for 30-day MACE. No MACE occurred in these groups giving both scores a sensitivity and negative predictive value of 100% (95% CI 91.6-100%), and respectively a specificity of 11.6% (95% CI 9.2-14.5%) and 17.1% (95% CI 14.2-20.5%). Use of both TIMI and HEART scores improved specificity further to 22.0% (95% CI 18.7-25.6%). Early H-FABP had a sensitivity of 41.5% (95% CI 27.8-56.6%) and a specificity of 91.1% (95% CI 88.4-93.2%). A modified TIMI score of zero or a HEART score of ≤2, incorporating a single hs-cTnT level, will identify patients with low risk of 30-day MACE for early discharge within 2 hours of ED arrival.