TIMI Risk Score Calculator
Score seven TIMI items and see the 14 day risk of death, heart attack, or urgent revascularization in UA or NSTEMI.
What it does
The TIMI risk score is a seven item tool for adults with unstable angina or non ST elevation myocardial infarction. It estimates the chance of death, a new myocardial infarction, or urgent revascularization within 14 days. The original study was published in 2000 and the score is still used in emergency departments and cardiology wards.
Each item is worth one point. The items are age 65 or older, three or more coronary risk factors, known coronary artery disease with at least 50 percent stenosis, aspirin use in the past week, severe angina in the past 24 hours, ST segment change of at least 0.5 mm, and a positive cardiac marker. The score is the count of items present.
Higher scores track with higher event rates. A score of 0 or 1 has a 14 day event rate near 4.7 percent, a score of 2 about 8.3 percent, a score of 3 about 13.2 percent, a score of 4 about 19.9 percent, a score of 5 about 26.2 percent, and a score of 6 or 7 about 40.9 percent. These rates come from the original cohort and are used as a reference, not a promise for an individual.
The score is often grouped into low, intermediate, and high risk. A common grouping is 0 to 2 for low, 3 to 4 for intermediate, and 5 to 7 for high. The grouping helps with communication, but the exact event rate is more useful for shared decisions. A patient with a score of 4 is not automatically sent for an invasive procedure, and a patient with a score of 2 is not automatically discharged.
TIMI was built before high sensitivity troponin and modern drug eluting stents became routine. Later studies show that it still separates risk, but it is less precise than newer tools that include troponin values, kidney function, and bleeding risk. Use it as one input. The ECG, the troponin trend, the patient's stability, and the bleeding profile remain central.
How to use
- Confirm the diagnosis is unstable angina or NSTEMI. Do not use this score for ST elevation myocardial infarction.
- Check the age. Add 1 point if the patient is 65 or older.
- Count coronary risk factors. Add 1 point if there are three or more among family history, high blood pressure, high cholesterol, diabetes, and current smoking.
- Add 1 point for known coronary artery disease with at least 50 percent stenosis, 1 point for aspirin use in the past 7 days, and 1 point for severe angina in the past 24 hours.
- Review the ECG for ST change of at least 0.5 mm and the troponin result. Add 1 point for each positive finding.
- Total the points, read the 14 day event rate, and combine the result with bleeding risk and the local chest pain pathway.
Formula
- Age
- 1 point when age is 65 or older.
- Risk factors
- 1 point for three or more of family history, hypertension, hypercholesterolemia, diabetes, or current smoking.
- Known CAD
- 1 point for known coronary stenosis of 50 percent or more.
- Aspirin
- 1 point for aspirin use in the past 7 days.
- Severe angina
- 1 point for two or more anginal episodes in the past 24 hours.
- ST change
- 1 point for transient ST elevation or depression of at least 0.5 mm.
- Marker
- 1 point for an elevated cardiac marker such as troponin.
The seven items are counted once each, even when more than one risk factor is present. The risk factor item is positive at three or more factors, not one point per factor. The score is for unstable angina and NSTEMI. It does not apply to STEMI, where reperfusion urgency is decided by the ECG and symptom timeline. The 14 day rates are from the original TIMI 11B cohort and may differ in contemporary populations.
Worked example
Example: score 4, 19.9 percent
A 68 year old smoker with high blood pressure and diabetes has two episodes of angina at rest in the past day and a positive troponin. The ECG shows no ST change and the patient has not taken aspirin.
- Age 65 or older: yes, 1 point.
- Three or more risk factors: smoking, high blood pressure, and diabetes, 1 point.
- Known coronary artery disease: no, 0 points. Aspirin in the past 7 days: no, 0 points.
- Severe angina in the past 24 hours: yes, 1 point.
- ST change: no, 0 points.
- Positive cardiac marker: yes, 1 point.
- Total: 1 + 1 + 0 + 0 + 1 + 0 + 1 = 4. The 14 day event rate for a score of 4 is 19.9 percent.
Reference table
| Score | 14 day death, MI, or urgent revascularization | Category |
|---|---|---|
| 0 to 1 | 4.7% | Low |
| 2 | 8.3% | Low |
| 3 | 13.2% | Intermediate |
| 4 (worked example) | 19.9% | Intermediate |
| 5 | 26.2% | High |
| 6 to 7 | 40.9% | High |
Limits
- The score was derived for unstable angina and NSTEMI. It should not be used for STEMI or for chest pain with a normal ECG and normal troponin.
- The original cohort predates high sensitivity troponin and modern invasive care, so the absolute rates may not match current practice.
- The score does not include bleeding risk, kidney function, or frailty, all of which affect treatment choices.
- The risk factor item depends on how many factors are documented, so incomplete history can lower the score.
Common mistakes
- Counting one point for each coronary risk factor instead of one point for having three or more.
- Applying the score to STEMI. Reperfusion in STEMI is time critical and follows a different pathway.
- Scoring a positive marker when the troponin is only mildly elevated from a non cardiac cause without clinical correlation.
- Using the score to decide discharge without considering serial troponins, ECG changes, and the patient's stability.
- Ignoring bleeding risk when a high score prompts a plan for potent antiplatelet therapy.
Try it yourself
Quick checks. Answers sit tucked under each question.
All seven items are present. What is the score and 14 day event rate?
7 points. The 14 day event rate for a score of 6 or 7 is 40.9 percent.
Only age 65 or older is present. What is the score and event rate?
1 point. The 14 day event rate for a score of 0 to 1 is 4.7 percent.
Age, three risk factors, and known CAD are present. What is the score and event rate?
3 points. The 14 day event rate for a score of 3 is 13.2 percent.
Questions
What does a TIMI score of 4 mean?
It means four of the seven items are present. The original 14 day rate for death, myocardial infarction, or urgent revascularization is 19.9 percent.
Is TIMI used for STEMI?
No. TIMI was built for unstable angina and NSTEMI. STEMI care is driven by the ECG and the time from symptom onset.
Does a high TIMI score require an angiogram?
It supports early risk review and often an invasive strategy, but the decision also depends on symptoms, ECG changes, troponin, bleeding risk, and patient preference.
How is the risk factor item counted?
It is one point when three or more of the listed factors are present. It is not one point per factor.
Can TIMI be used in the emergency department?
Yes, it is often used there, but only after the ECG and troponin are available and the diagnosis fits unstable angina or NSTEMI.
Why do the event rates look old?
They come from a 2000 cohort. Contemporary care has changed, so use the rates as a relative guide rather than an exact prediction.