What does the TIMI score predict?

The TIMI score for NSTEMI/UA predicts the combined 14-day rate of all-cause mortality, new or recurrent myocardial infarction, and severe recurrent ischemia requiring urgent revascularization. It does not predict long-term outcomes beyond 14 days.

What is the difference between low, intermediate, and high TIMI risk?

A score of 0-2 is low risk (approximately 5% 14-day event rate), 3-4 is intermediate risk (approximately 13-20%), and 5-7 is high risk (approximately 26-41%). Higher scores support earlier invasive evaluation and more aggressive antithrombotic therapy.

Does the TIMI score apply to STEMI?

No. There is a separate TIMI Risk Score for STEMI that uses different criteria. The calculator on this page applies only to non-ST-elevation MI (NSTEMI) and unstable angina (UA).

What counts as a CAD risk factor for the TIMI score?

The original TIMI study defined CAD risk factors as: family history of CAD, hypertension, hypercholesterolemia, diabetes mellitus, and current active smoking. Having three or more of these qualifies for this criterion.

What qualifies as elevated serum cardiac markers?

Elevation of any serum cardiac marker above the institution's upper limit of normal qualifies, including troponin I, troponin T, or CK-MB. Even a minimally elevated troponin counts as a positive criterion.

Is this tool a replacement for clinical judgment?

No. The TIMI score is a decision support aid and should be interpreted alongside the full clinical picture, ECG findings, serial biomarkers, patient preferences, and institutional capabilities. It is not intended as a standalone discharge or admission decision tool.

TIMI Score for NSTEMI/UA

Select the 7 TIMI criteria to calculate the risk score and estimate 14-day all-cause mortality, new MI, or severe recurrent ischemia requiring revascularization.

TIMI Criteria (1 point each)

Age ≥ 65 years

Patient is 65 years of age or older at time of presentation

≥ 3 CAD risk factors

Family history of CAD, hypertension, hypercholesterolemia, diabetes mellitus, or active smoking — at least 3 present

Prior coronary stenosis ≥ 50%

Known prior coronary artery stenosis of 50% or more on catheterization

ST-segment deviation on presenting ECG

New or presumed new ST-segment depression or transient ST elevation on initial 12-lead ECG

≥ 2 anginal events in the prior 24 hours

Two or more episodes of rest angina or anginal symptoms in the 24 hours before presentation

Aspirin use in the prior 7 days

Patient was taking aspirin in the 7 days before the index event (suggests aspirin-refractory disease)

Elevated serum cardiac markers

Troponin I, troponin T, or CK-MB above the institution's upper limit of normal

TIMI Risk Score

0 / 7

Low Risk

14-day event rate: ~5%

Score progress (0-7)

Clinical Interpretation

A score of 0 reflects no identified risk factors. Standard care is appropriate; consider serial ECGs and biomarkers per protocol.

Risk Stratification Reference

Score	Risk Category	14-Day Event Rate
0 / 1	Low	~5%
2	Low	~8%
3	Intermediate	~13%
4	Intermediate	~20%
5	High	~26%
6	High	~41%
7	High	~41%

Event = all-cause mortality, new/recurrent MI, or severe recurrent ischemia requiring urgent revascularization at 14 days. Rates from the original TIMI 11B/ESSENCE pooled analysis.

Medical Disclaimer: This tool is for educational and clinical decision support purposes only. It does not constitute medical advice and must not be used as the sole basis for treatment decisions. Always apply clinical judgment, consult current guidelines, and involve qualified healthcare professionals in patient care decisions.

Summary

The TIMI (Thrombolysis in Myocardial Infarction) Risk Score for NSTEMI/UA is a validated clinical decision aid developed from the TIMI 11B and ESSENCE trials. It uses seven equally weighted binary criteria to estimate a patient's risk of all-cause mortality, new or recurrent MI, or severe recurrent ischemia requiring urgent revascularization within 14 days of presentation. Scores range from 0 to 7 and are grouped into low (0-2), intermediate (3-4), and high (5-7) risk categories, each associated with increasing event rates. The tool is widely used in emergency medicine and cardiology to guide intensity of treatment and early invasive strategy decisions.

How it works

Review the seven clinical criteria listed on the left panel.
Check each criterion that applies to the patient at the time of presentation.
Each checked criterion adds 1 point to the total score (range 0-7).
The risk panel on the right updates instantly with the score, risk category, and estimated 14-day event rate.
Use the result alongside clinical judgment to guide treatment intensity and disposition.
Click "Reset" to clear all selections for a new patient.

Use cases

Emergency department triage of chest pain patients presenting with NSTEMI or unstable angina.
Cardiology consultation to determine need for early invasive versus conservative strategy.
Medical education and exam preparation for USMLE, cardiology boards, and emergency medicine training.
Bedside risk communication with patients and families during acute coronary syndrome workup.
Quality improvement and protocol development for ACS pathways.

Frequently Asked Questions

Last updated: 2026-09-30 · Reviewed by Nham Vu