Acute coronary syndrome (ACS) affects approximately 805,000 Americans each year, including 605,000 first events and 200,000 recurrent events. ACS refers to a sudden reduction in blood flow to the heart, most often caused by erosion or rupture of unstable coronary artery plaque and subsequent thrombosis.

ACS comprises three clinical conditions that represent a spectrum of severity:

• Unstable angina
• Non–ST-segment elevation myocardial infarction (NSTEMI) 
• ST-segment elevation myocardial infarction (STEMI)

Proper management for each of these conditions is key to reducing both immediate and long-term complications. Despite its prevalence and potentially life-threatening consequences, awareness of ACS symptoms, risk factors, and the importance of timely treatment remains critical.

(link opens in new window)(link opens in new window)2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients with ACS

When evaluating acute chest pain in the emergency department, the goals are to identify life-threatening causes, determine clinical stability and decide whether hospitalization or outpatient management is appropriate. The AHA/ACC guidelines classify chest pain into four categories: STEMI, NSTE-ACS, stable angina and noncardiac. A 12-lead ECG, performed within 10 minutes of arrival, is key for identifying STEMI and guiding urgent treatment, while ST-T abnormalities signaling ischemia require prompt evaluation.   (Gulati et al., 2021)

 

Due to its high sensitivity and specificity for myocardial tissue, cardiac troponin (cTn) is the most reliable biomarker for diagnosing acute myocardial injury, especially when combined with other key clinical information (e.g., patient history, examination, ECG). Measuring cTn is crucial for determining the right treatment pathway for acute chest pain patients, and delays in testing can be harmful.  (Gulati et al., 2021) 

Incorporating an evidence-based risk stratification score can assist emergency departments in deciding if acute chest pain patients are at low, intermediate or high risk for acute coronary syndrome (ACS). Patients presenting with acute chest pain and suspected ACS exhibit a broad range of risk profiles.

After excluding STEMI, it becomes essential to classify these patients into low, intermediate or high-risk categories to inform appropriate management strategies. Chest pain risk scores assist in this process by providing a comprehensive evaluation that incorporates clinical data such as patient age, ECG findings (e.g., ST segment changes), symptom characteristics, coronary artery disease risk factors and cardiac troponin (cTn) levels to estimate the likelihood of ACS or the risk of experiencing major adverse cardiovascular events (MACE) within 30 days.  (Gulati et al., 2021)