TIMI STEMI
TIMI risk score for STEMI: predict 30-day mortality. 8 criteria: age, Killip class, HR, BP, ECG, time, weight. Free online clinical risk assessment tool.
About This Calculator
The TIMI (Thrombolysis In Myocardial Infarction) risk score for STEMI is a clinically validated bedside scoring system that predicts 30-day mortality in patients presenting with ST-elevation myocardial infarction. Developed by Morrow et al. in 2000 from the InTIME II trial data and subsequently validated in NRMI-3 and international cohorts, the TIMI STEMI score helps clinicians identify high-risk patients who may benefit from intensive monitoring and aggressive reperfusion therapy.
The score comprises 8 weighted clinical criteria: age (65-74 years: 2 points; ≥75 years: 3 points), history of diabetes/hypertension/angina (1 point), heart rate >100 bpm (2 points), Killip class II-IV indicating heart failure (2 points), systolic blood pressure <100 mmHg (3 points), anterior lead ST elevation or left bundle branch block on ECG (1 point), time to reperfusion therapy >4 hours (1 point), and body weight <67 kg (1 point). The total score ranges from 0 to 14, with higher scores correlating to progressively higher 30-day mortality (0.8% at score 0 to 35.9% at score 9+).
Regional Notes
US: The TIMI STEMI score is widely used in American emergency departments and cardiac care units per ACC/AHA guidelines for STEMI risk stratification. Primary PCI is the preferred reperfusion strategy within 90 minutes of first medical contact.
UK: NICE guidelines (NG185) recommend the TIMI score as part of the initial assessment of STEMI patients. The UK typically uses primary PCI with a target of 120 minutes from diagnosis to balloon inflation.
India: The TIMI STEMI score is increasingly adopted across Indian cardiology centers. Given the high burden of premature CAD in India, the score's weighting for diabetes and hypertension is particularly relevant for risk stratification in the Indian population.
Frequently Asked Questions
What is the TIMI risk score for STEMI?
The TIMI (Thrombolysis In Myocardial Infarction) risk score for STEMI is a validated clinical scoring system that predicts 30-day mortality in patients with ST-elevation myocardial infarction. It uses 8 weighted criteria — age, diabetes/hypertension/angina, heart rate, Killip class, systolic blood pressure, ECG findings, time to treatment, and body weight — to calculate a score from 0-14, where higher scores indicate greater mortality risk.
How is the TIMI STEMI score calculated?
The TIMI STEMI score assigns weighted points across 8 criteria: age 65-74 (2 pts) or ≥75 (3 pts); diabetes, hypertension, or angina history (1 pt); heart rate >100 bpm (2 pts); Killip class II-IV (2 pts); systolic BP <100 mmHg (3 pts); anterior ST elevation or LBBB on ECG (1 pt); time to treatment >4 hours (1 pt); and weight <67 kg (1 pt). The maximum possible score is 14 points.
What do different TIMI STEMI scores mean?
Score 0: 0.8% mortality (low risk). Score 1: 1.6%. Score 2: 2.2%. Score 3: 4.4%. Score 4: 7.3%. Score 5: 12.4%. Score 6: 16.1%. Score 7: 23.4%. Score 8: 26.8%. Score 9-14: 35.9% mortality (high risk). Scores 0-3 are classified as low risk, 4-6 as moderate risk, and 7-14 as high risk for 30-day mortality.
Who developed the TIMI risk score for STEMI?
The TIMI risk score for STEMI was developed by Morrow et al. in 2000 based on data from the InTIME II trial. It was subsequently validated in the National Registry of Myocardial Infarction 3 (NRMI-3) and numerous other international cohorts, confirming its reliability as a bedside risk stratification tool.
Can this calculator replace a doctor's assessment?
No. This calculator is for educational and reference purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. The TIMI score is an adjunctive tool that should be used alongside comprehensive clinical assessment by a qualified healthcare provider. Always consult a physician for any medical decisions.
What is the Killip classification?
Killip classification (Killip-Kimball class) is a 4-grade system to assess heart failure severity in acute MI. Class I: no signs of heart failure. Class II: rales/crackles, S3 gallop, elevated JVP. Class III: acute pulmonary edema. Class IV: cardiogenic shock with hypotension, oliguria, and cyanosis. Killip class II-IV in the TIMI score predicts significantly higher mortality.
How does TIMI STEMI differ from TIMI UA/NSTEMI?
The TIMI STEMI score is specifically designed for patients with ST-elevation myocardial infarction (STEMI) and uses weighted criteria including Killip class, time to treatment, and body weight. The TIMI UA/NSTEMI score is a separate 7-point scoring system for unstable angina and non-ST-elevation MI, using factors like age ≥65, coronary artery disease risk factors, and cardiac enzyme elevation. They serve different patient populations and should not be used interchangeably.
Is the TIMI STEMI score used worldwide?
Yes, the TIMI STEMI risk score is validated and used internationally in the US, UK, India, and across Europe and Asia. It was derived from multinational trial data and has been externally validated in diverse populations, including Indian, European, and North American cohorts. The score is applicable regardless of geographic region when using consistent clinical assessment criteria.