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

Abstract

Background: The current evaluation of patients with chest pain presenting to an emergency department (ED) with suspected acute coronary syndrome (ACS) is a lengthy process involving serial measurements of troponin.

Objective: We aimed to validate the diagnostic accuracy of a Thrombolysis in Myocardial Infarction (TIMI) score with single high-sensitive cardiac troponin T (hs-cTnT) for 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 (history, electrocardiogram, age, risk factors, troponin) score.

Methods: We recruited 602 consecutive adult patients with chest pain and suspected ACS in the ED. Each patient had TIMI and HEART scores, and a point-of-care H-FABP test.

Results: MACE occurred in 42 (7.0%) patients within 30 days. A low risk for 30-day MACE was identified by a modified TIMI score of 0 in 65 (11%) patients, and by a HEART score ≤ 2 in 96 (16%) patients. No MACE occurred in these groups, giving both scores a sensitivity of 100% (95% confidence interval [CI] 91.6-100%), and specificity of 11.6% (95% CI 9.2-14.5%) and 17.1% (95% CI 14.2-20.5%), respectively. Use of combined TIMI and HEART scores improved the specificity further to 22.0% (95% CI 18.7-25.6%) without lowering sensitivity. Early H-FABP measurement > 7 μg/L had a sensitivity of 41.5% (95% CI 27.8-56.6%) and a specificity of 91.1% (95% CI 88.4-93.2%) for predicting 30-day MACE.

Conclusions: A modified TIMI score of 0 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 h of ED arrival.

Keywords: acute coronary syndrome; chest pain; diagnosis; major adverse cardiac event.