About the TIMI Risk Score for UA/NSTEMI
The Thrombolysis in Myocardial Infarction (TIMI) Risk Score for UA/NSTEMI was developed by Antman et al. (2000) from the TIMI 11B trial data. It assigns one point for each of seven independent predictors of 14-day adverse outcomes (all-cause mortality, new or recurrent MI, or need for urgent revascularisation) in patients with confirmed unstable angina or NSTEMI.
Event Rate by TIMI Score
| TIMI Score | 14-Day Event Rate | Risk Category |
|---|---|---|
| 0–1 | ~5% | Low |
| 2 | ~8% | Low |
| 3 | ~13% | Intermediate |
| 4 | ~20% | Intermediate |
| 5 | ~26% | High |
| 6–7 | ~41% | High |
TIMI vs HEART Score — When to Use Each
TIMI is designed for patients with confirmed UA or NSTEMI — it is used after ACS is established to guide invasive vs conservative management. The HEART Score is more appropriate for undifferentiated chest pain triage in the emergency department, before a diagnosis of ACS has been established. Use HEART first; use TIMI after ACS confirmation.
Management Strategy Guidance
| TIMI Score | Strategy | Guideline Basis |
|---|---|---|
| 0–2 (Low) | Conservative (selective invasive) | ACC/AHA IIa recommendation for early invasive if refractory symptoms |
| 3–4 (Intermediate) | Early invasive acceptable | ACC/AHA I recommendation — invasive strategy reduces events |
| 5–7 (High) | Early invasive recommended | ACC/AHA I recommendation — urgent angiography within 24–48h |
Related Tools on MediCalc Pro
For initial undifferentiated chest pain triage, use HEART Score before TIMI. For cardiovascular risk factors contributing to TIMI criteria, see Framingham Risk Score. For QTc monitoring during antiarrhythmic therapy, see QTc Calculator. For anticoagulation in AF, see CHA₂DS₂-VASc Score. For DVT/PE risk, see Wells Score. For renal function impacting DOAC dosing, see Creatinine Clearance.
References
- Antman EM, 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.
- Amsterdam EA, et al. "2014 AHA/ACC Guideline for the management of patients with non-ST-elevation acute coronary syndromes." JACC. 2014;64(24):e139-228.
- Collet JP, et al. "2020 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation." Eur Heart J. 2021;42(14):1289-1367.