Cardiology

TIMI Risk Score (UA/NSTEMI)

7-point risk score for unstable angina and NSTEMI. Predicts 14-day all-cause mortality, new MI, and urgent revascularisation. Guides early invasive versus conservative management per ACC/AHA guidelines.

Antman et al. 2000 14-day event prediction PDF export
TIMI Criteria (UA/NSTEMI)
TIMI Result
-
out of 7
-
14-day all-cause mortality / MI / urgent revascularisation

Risk stratification:

0-2
Low risk
~5% 14-day events
3-4
Intermediate
~13% 14-day events
5-7
High risk
~26% 14-day events

TIMI Risk Score for UA/NSTEMI

The Thrombolysis in Myocardial Infarction (TIMI) Risk Score was published by Antman et al. in 2000. It assigns one point for each of 7 predictors of 14-day adverse outcomes in confirmed unstable angina or NSTEMI. The original derivation study is indexed on PubMed.

Event rate by score

Score14-Day Event RateStrategy
0-1~5%Conservative
2~8%Conservative (monitor closely)
3~13%Early invasive acceptable
4~20%Early invasive recommended
5~26%Urgent early invasive
6-7~41%Urgent angiography within 2-24h

Intermediate and high-risk patients are typically started on anticoagulation alongside antiplatelet therapy; renal function should be checked before dosing, our Creatinine Clearance Calculator covers the equations most anticoagulant dosing tables reference.

TIMI vs HEART Score

HEART Score is for undifferentiated chest pain in the ED, before ACS is confirmed. TIMI is for patients with a confirmed UA or NSTEMI diagnosis, guiding the next decision: invasive or conservative. Use HEART first, TIMI after confirmation. If the presentation also raises suspicion for pulmonary embolism, the Wells Score should be applied in parallel rather than as an afterthought once ACS has been excluded.

TIMI and the 2025 ACC/AHA/ACEP/NAEMSP/SCAI ACS Guideline

The invasive-versus-conservative thresholds referenced above come from the 2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes, which formally retired and replaced the 2014 NSTE-ACS guideline this score was originally validated against. The TIMI score itself, and its published event rates, remain unchanged; only the downstream guideline-directed management recommendations have been updated.

Frequently Asked Questions

Can I use TIMI for chest pain before ACS is confirmed?+
No. TIMI was derived and validated only in patients with a confirmed diagnosis of unstable angina or NSTEMI. For undifferentiated chest pain where the diagnosis is not yet known, use the HEART Score instead, then move to TIMI once UA or NSTEMI is confirmed.
What counts as a CAD risk factor for the TIMI score?+
The three-or-more risk factor criterion counts family history of coronary artery disease, hypertension, hypercholesterolaemia, diabetes, and active smoking. A patient needs three or more of these five factors present to score the point for that criterion.
Does a TIMI score of 0 rule out a cardiac event?+
No. Even a TIMI score of 0-1 still carries an approximately 5% 14-day event rate in the original validation cohort. TIMI stratifies relative risk to guide management intensity, it does not rule out events entirely, and clinical judgement, serial troponins, and ECG changes still matter regardless of the numeric score.

Related tools

For undifferentiated chest pain triage, see HEART Score. For 10-year CVD risk, see Framingham Risk Score. For QTc monitoring during antiarrhythmic therapy, see QTc Calculator.

References

  • Antman EM, et al. "The TIMI risk score for unstable angina/non-ST elevation MI." JAMA. 2000;284(7):835-842.
  • Amsterdam EA, et al. "2014 AHA/ACC Guideline for NSTE-ACS." JACC. 2014;64(24):e139-228. Superseded by the 2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes.
Clinical note: TIMI is a risk stratification tool, not a diagnosis. All management decisions require comprehensive clinical assessment and cardiologist input.