Table 1 Risk stratification tools

HFA ¹⁶

High risk

Presentation with clinical features consistent with ACS and any of:

• Repetitive or prolonged (>10 min) ongoing chest pain/discomfort

• Elevation of at least one cardiac biomarker (troponin or CK-MB)

• Persistent of dynamic ST depression ≥0.5 mm or new T wave inversion ≥2 mm

• Transient ST segment elevation (≥0.5 mm) in more than two contiguous leads

• Hemodynamic compromise: systolic BP <90 mmHg, cool peripheries, diaphoresis, Killip class >1 and/or new onset mitral regurgitation

• Sustained ventricular tachycardia or syncope

• Left ventricular systolic dysfunction (LVEF <40%)

• Prior PCI within 6 months or prior CABG

• Presence of known diabetes or chronic kidney disease (eGFR <60 ml/min) with typical symptoms of ACS

Intermediate risk

Presentation with clinical features consistent with ACS and any of:

• Chest pain or discomfort within the past 48 h that occurred at rest or was repetitive or prolonged (but currently resolved)

• Age >65 years

• Known coronary artery disease: prior MI with LVEF ≥40% or known coronary lesion >50% stenosis

• No high-risk ECG changes

• Two or more of: known hypertension, family history, active smoking and hyperlipidemia

• Presence of known diabetes or chronic kidney disease (eGFR <60 ml/min) with atypical symptoms of ACS

• Prior aspirin use

AND NOT meeting the criteria for high-risk NSTEACS

Low risk

Presentation with clinical features consistent with ACS without intermediate- or high-risk features

• Onset of angina symptoms within the last month

• Worsening in severity or frequency of angina

• Lowering in angina threshold

TIMI RS ¹⁹

1 point for each positive factor

• Age >65 years

• Documented prior coronary artery stenosis >50% or prior cardiac catheterization with known disease or PCI or prior CABG or documented prior myocardial infarction

• 3 or more conventional cardiac risk factors (hypertension, diabetes, cholesterol elevation, family history of coronary artery disease/MI, history of tobacco use)

• Use of aspirin in the preceding 7 days

• 2 or more angina events in the past 24 h

• ST-segment elevation or depression >1 mm

• Elevated cardiac biomarkers

Goldman ⁶

Very low risk

• No ECG evidence of acute ischemia/MI and none of the following urgent factors:

▪ Rales above both lung bases

▪ Systolic BP <100 mmHg

▪ Unstable IHD (worsening of previously stable angina, new onset of post-infarction angina or angina after a coronary revascularization procedure or pain that was the same as associated with a prior MI)

Low risk

No ECG evidence of acute ischemia/MI and 1 of above urgent factors

Moderate risk

No ECG evidence of acute ischemia/MI and 2 or 3 of above urgent factors

OR ECG evidence of acute ischemia AND 0 or 1 of above urgent factors

High risk

ECG evidence of AMI alone OR ECG evidence of acute ischemia with 2 or 3 of above urgent factors