Critical Issues in the Evaluation and Management of Emergency Department Patients With Suspected Non-ST-Elevation Acute Coronary Syndromes

In adult patients without evidence of ST-elevation acute coronary syndrome, the History, electrocardiogram [ECG], Age, Risk factors, Troponin (HEART) score can be used as a clinical prediction instrument for risk stratification. A low score (≤3) predicts a 30-day major adverse cardiac event miss rate within a range of 0% to 2%.

In adult patients without evidence of ST-elevation acute coronary syndrome, other risk-stratification tools, such as Thrombolysis in Myocardial Infarction (TIMI), can be used to predict a rate of 30-day major adverse cardiac event.

In adult patients with suspected acute non–ST-elevation acute coronary syndrome, conventional troponin testing at 0 and 3 hours among low-risk acute coronary syndrome patients (defined by HEART score 0 to 3) can predict an acceptable low rate of 30-day major adverse cardiac events.

A single high-sensitivity troponin result below the level of detection on arrival to the emergency department, or negative serial high-sensitivity troponin result at 0 and 2 hours is predictive of a low rate of major adverse cardiac events.

In adult patients with suspected acute non–ST-elevation acute coronary syndrome who are determined to be low risk based on validated accelerated diagnostic pathways that include a nonischemic electrocardiogram (ECG) result and negative serial high-sensitivity troponin testing results both at presentation and at 2 hours can predict a low rate of 30-day major adverse cardiac events allowing for an accelerated discharge pathway from the emergency department.

Do not routinely use further diagnostic testing (coronary computed tomography [CT] angiography, stress testing, myocardial perfusion imaging) prior to discharge in low-risk patients in whom acute myocardial infarction has been ruled out to reduce 30-day major adverse cardiac events.

Arrange follow-up in 1 to 2 weeks for low-risk patients in whom myocardial infarction has been ruled out. If no follow-up is available, consider further testing or observation prior to discharge (consensus recommendation).

P2Y12 inhibitors and glycoprotein IIb/IIIa inhibitors may be given in the emergency department or delayed until cardiac catheterization.