ACS - Risk Stratification


  • The score has been derived and validated in an ED population and predicts 6 week adverse cardiac events[1][2]
  • Low risk patients have a score 0-3 and have a less than 2% risk of MACE at 6 weeks.
Criteria Point Value
Highly Suspicious +2
Moderately Suspicious +1
Slightly Suspicious 0
Significant ST-depression +2
Non specific repolarisation disturbance +1
Normal 0
≥ 65 +2
45-65 +1
≤ 45 0
Risk Factors (Hypercholesterolemia, Hypertension, Diabetes Mellitus, Smoking,Obesity)
≥ 3 risk factors or history of atherosclerotic disease +2
1-2 risk factors +1
No risk factors known 0
≥ 3× normal limit +2
1-3× normal limit +1
≤ normal limit 0
  • 0-3: 2.5% risk of adverse cardiac event. Patient's can be discharged with follow-up.
  • 4-6: 20.3% risk of adverse cardiac event. Patients should be admitted to the hospital for trending of troponin and provocative testing.
  • ≥7: 72.7% risk of adverse cardiac event, suggesting early invasive measures with these patients and close coordination with inpatient cardiology

New Vancouver Chest Pain Rule

  • Useful for screening patient with low risk for ACS
  • The old Vancouver chest pain rule was not properly validated[3][4] [4]
  • The new rule was validated in 2014 on 1635 patients and published in 2014[5]
  • With high sensitivity troponins the sensitivity is 99.1% (95% CI 97.4-99.7), & specificity is 16.1 (95% CI 14.2-18.2)
  • With sensitive troponin-I the sensitivity was 98.8% (97.0-99.5), & specificity of 15.8 (13.9-17.9)


  • Is the same for c-TnI assay and hs-TnI assay but sensitivity differences by a percentage point
  1. Is there an abnormal ECG, positive troponin at 2 hrs or prior ACS nitrate use?
    • If Yes to any then no early discharge
  2. Does palpation reproduce the pain?
    • If Yes then early discharge
  3. Age ≥50, or does pain radiate to neck, jaw, or left arm?
    • If Yes then no early discharge
  • If answer is No to all of the above stepwise questions then the patient can have early discharge with close follow-up for further provocative testing

Likelihood That Signs/Symptoms Represent ACS due to CAD

Feature High Likelihood (any of the following) Intermediate Likelihood (absence of high-likelihood features and presence of any of the following) Low Likelihood (absence of high- or intermediate-likelihood features but may have)
History Chest or left arm pain or discomfort as chief symptom reproducing prior documented angina Chest or left arm pain or discomfort as chief symptom Probable ischemic symptoms in absence of any of the intermediate-likelihood characteristics
Known history of coronary artery disease, including myocardial infarction Age >70 y old Recent cocaine use
Male sex
Diabetes mellitus
Examination Transient mitral regurgitation murmur, hypotension, diaphoresis, pulmonary edema, or rales Extracardiac vascular disease Chest discomfort reproduced by palpation
ECG New, or presumably new, transient ST-segment deviation (1 mm or greater) or T-wave inversion in multiple precordial leads Fixed Q waves T-wave flattening or inversion <1 mm in leads with dominant R waves
ST depression 0.5–1.0 mm or T-wave inversion >1 mm
Normal ECG
Cardiac markers Elevated cardiac troponin I, troponin T, or MB fraction of creatine kinase Normal Normal

Short-Term Risk of Composite Outcome

Composite Outcome: Death or Nonfatal Myocardial Infarction by Risk Stratification in Patients with Unstable Angina

Feature High Likelihood (at least one of the following features must be present) Intermediate Likelihood (no high-risk feature, but must have one of the following) Low Likelihood (no high- or intermediate-risk feature, but may have any of the following)
History Accelerating tempo of ischemic symptoms in preceding 48 h Prior myocardial infarction, peripheral or cerebrovascular disease, or coronary artery bypass grafting; prior aspirin use
Character of the pain Prolonged ongoing (>20 min) rest pain Prolonged (>20 min) rest angina, now resolved, with moderate or high likelihood of CAD Increased angina frequency, severity, or duration
Rest angina (>20 min) or relieved with rest or sublingual nitroglycerin Angina provoked at a lower threshold
New-onset angina with onset 2 wk to 2 mo before presentation
Nocturnal angina
New-onset or progressive Canadian Cardiology Society Class III or IV angina in the past 2 wk without prolonged (>20 min) rest pain but with intermediate or high likelihood of CAD;  
Clinical findings Pulmonary edema, most likely due to ischemia Age >70 y old Chest discomfort reproduced by palpation
New or worsening mitral regurgitation murmur
S3 or new/worsening rales
Hypotension, bradycardia, tachycardia
Age >75 y old
ECG Angina at rest with transient ST-segment changes >0.5 mm T-wave changes, pathologic Q waves, or resting ST depression <1 mm in multiple lead groups (anterior, inferior, lateral) Normal or unchanged ECG
Bundle-branch block, new or presumed new
Sustained ventricular tachycardia
Cardiac markers Elevated cardiac TnT, TnI, or CK-MB (e.g., TnT or TnI >0.1 nanogram/mL) Slightly elevated cardiac TnT, TnI, or CK-MB (e.g., TnT >0.01 but <0.1 nanogram/mL) Normal

TIMI Risk Stratification Score


Used to estimate percent risk of all-cause mortality, new/recurrent MI, or need for revascularization at 14 days
  • Age >65 yrs (1 point)
  • Three or more risk factors for coronary artery disease: (1 point)
    • family history of coronary artery disease
    • hypertension
    • hypercholesterolaemia
    • diabetes
    • current smoker
  • Use of aspirin in the past 7 days (1 point)
  • Significant coronary stenosis (stenosis >50%) (1 point)
  • Severe angina (e.g., >2 angina events in past 24 h or persisting discomfort) (1 point)
  • ST-segment deviation of ≥0.05 mV on first ECG (1 point)
  • Increased troponin and/or creatine kinase-MB blood tests (1 point)
TIMI Risks
points % risk of mortality, MI, or need for revascularization
0 5%
1 5%
2 8%
3 13%
4 20%
5 26%
6 41%

See Also


  1. Six AJ, Backus BE, Kelder JC. Chest pain in the emergency room: value of the HEART score. Neth Heart J. 2008 Jun;16(6):191-6.PMID 18665203
  2. Backus BE, Six AJ, Kelder JC, Bosschaert MA. et al. A prospective validation of the HEART score for chest pain patients at the emergency department. Int J Cardiol. 2013 Oct 3;168(3):2153-8 PMID 2346525
  3. Jalili M. Validation of the Vancouver Chest Pain Rule: a prospective cohort study. Acad Emerg Med. 2012 Jul;19(7):837-42.
  4. 4.0 4.1 Christenson J. A clinical prediction rule for early discharge of patients with chest pain. Ann Emerg Med. 2006 Jan;47(1):1-10.
  5. Cullen L et al. The new Vancouver Chest Pain Rule using troponin as the only biomarker: an external validation study. Am J Emerg Med. 2014 Feb;32(2):129-34
  6. Antman, Elliot et al. The TIMI Risk Score for Unstable Angina/Non–ST Elevation MI A Method for Prognostication and Therapeutic Decision Making. JAMA. 2000;284(7):835-842. doi:10.1001/jama.284.7.835. PDF