TIMI STEMI Risk Score Calculator
The TIMI Risk Score for STEMI quantifies 30-day mortality risk in patients with ST-elevation MI receiving fibrinolytic therapy. Select each risk factor to compute the score and estimated mortality.
Age group
Diabetes, hypertension, or angina history (+1)
Systolic BP < 100 mmHg (+3)
Heart rate > 100 bpm (+2)
Killip class II–IV (+2)
Weight < 67 kg (147 lb) (+1)
Anterior ST-elevation or LBBB (+1)
Time to fibrinolytic therapy > 4 hours (+1)
Low risk — est. 30-day mortality 0.8 %
- 1
Age group points
0Age < 65 yr = 0 pts; 65–74 yr = 2 pts; ≥ 75 yr = 3 pts. - 2
Haemodynamic risk points
SBP<100 (0) + HR>100 (0) + Killip II–IV (0) = 0 - 3
Clinical history points
DM/HTN (0) + wt<67 kg (0) + ant. STE/LBBB (0) + late Rx (0) = 0 - 4
TIMI STEMI score
0 + 0 + 0 = 0
How does this calculator work?
TIMI STEMI Score (0–14) = age points + weighted clinical variables at presentation. 30-day mortality: score 0 → 0.8%, score 5 → 12%, score ≥ 8 → 26.8% (Morrow 2000). Developed for fibrinolytic-treated STEMI — not validated for primary PCI. For reference only; clinical judgment is essential.
Formula
How this is calculated
The TIMI (Thrombolysis In Myocardial Infarction) Risk Score for STEMI was derived by Morrow et al. (JAMA 2000;284:835–842) from the InTIME II trial of 15,059 patients. It assigns weighted points to eight clinical variables present at hospital presentation: three points each for age ≥ 75 years and systolic BP < 100 mmHg; two points each for heart rate > 100 bpm and Killip class II–IV; one point each for age 65–74 years (if not ≥ 75), history of diabetes/hypertension/angina, body weight < 67 kg (147 lb), anterior ST-elevation or left bundle-branch block, and time from symptom onset to fibrinolytic treatment > 4 hours. The maximum score is 14.
Estimated 30-day all-cause mortality rises steeply with the score: from 0.8 % at score 0 to 26.8 % at score ≥ 8. The score was validated for patients receiving fibrinolytic (thrombolytic) therapy specifically; it is not designed for primary PCI (percutaneous coronary intervention) populations, for whom separate risk tools such as the Primary PCI TIMI score or GRACE score are more appropriate.
This calculator is for reference and education only. Clinical decision-making for STEMI patients requires real-time physician assessment, continuous monitoring and integration of findings beyond what any single score can capture. Mortality estimates are from the original 2000 trial population and may not reflect outcomes with modern reperfusion strategies and pharmacotherapy.
Frequently asked questions
The TIMI Risk Score for STEMI is used to estimate 30-day all-cause mortality risk in patients presenting with ST-elevation MI who are candidates for fibrinolytic (clot-busting) therapy. It helps clinicians rapidly stratify risk at the bedside using information available on presentation — no laboratory values are required.
The Killip classification grades heart failure severity in acute MI: Class I = no heart failure signs; Class II = S3 gallop or pulmonary rales in < 50% of lung fields; Class III = pulmonary oedema (rales > 50%); Class IV = cardiogenic shock. Killip class II–IV scores +2 points and is associated with significantly higher mortality.
No. The original TIMI STEMI score was derived and validated in fibrinolytic-treated patients from the InTIME II trial (2000). Primary PCI, now the preferred reperfusion strategy where available, has different outcomes and risk profiles. For PCI-treated STEMI patients, consider the GRACE score or the PCI-specific TIMI score.
Also known as
TG we-Calculate Editorial Team. (2026). TIMI STEMI Risk Score Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/timi-stemi-calculator
TG we-Calculate Editorial Team. "TIMI STEMI Risk Score Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/timi-stemi-calculator.
TG we-Calculate Editorial Team, "TIMI STEMI Risk Score Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/timi-stemi-calculator
@misc{wecalculate_timi_stemi_calculator, title = {TIMI STEMI Risk Score Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/timi-stemi-calculator}}, year = {2026}, note = {TG we-Calculate} }
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