The study suggests patients presenting with a normal ECG, TIMI score of zero, and negative highly sensitive troponin I assay may be safely discharged from the ED, but it needs validation.

In the ongoing search for the best approach to determine which patients with chest pain can be safely discharged from the emergency department (ED), researchers evaluated outcomes in adult patients who presented with nontraumatic chest pain and were evaluated for acute coronary syndrome at an academic hospital in Australia. Patients were considered low risk if they had a normal electrocardiogram (ECG), a presentation TIMI risk score of zero (see table), and an initial highly sensitive troponin I level 99th percentile.

The primary outcome was experiencing a major adverse cardiac event (MACE) — defined as death, cardiac arrest, revascularization, cardiogenic shock, arrhythmia, or prevalent (the cause for the presentation) or incident (occurring within the follow-up period) myocardial infarction — within 7 days; the secondary outcome was MACE within 30 days. Follow-up was by structured record review and telephone interview.

Of 651 patients studied, 215 met the low-risk criteria. One patient (0.47%) had a MACE (revascularization within 7 days). The negative predictive value of low-risk criteria was 99.5% at both 7 and 30 days, and the negative likelihood ratio was 0.005.

CITATION(S):

Kelly A-M. What is the incidence of major adverse cardiac events in emergency department chest pain patients with a normal ECG, thrombolysis in myocardial infarction score of zero and initial troponin 99th centile: An observational study? Emerg Med J 2013 Jan; 30:15.