TIMI Score Calculator for UA/NSTEMI
Calculate the TIMI risk score and estimated 14-day event risk using seven clinical predictors. TIMI Score Calculator for UA/NSTEMI helps healthcare professionals assess risk and support treatment decisions for patients with acute coronary syndromes.
Highlights
- Calculates the TIMI risk score for patients with unstable angina or NSTEMI.
- Uses seven validated clinical predictors for a structured risk assessment.
- Estimates the 14-day risk of death, myocardial infarction, or urgent revascularization.
- Accounts for age, CAD risk factors, aspirin use, angina, ECG changes, and cardiac markers.
- Provides an easy-to-understand risk category to support clinical decision-making.
Table of Contents
How TIMI Score Calculator for UA/NSTEMI Works?
The TIMI score for unstable angina and non-ST-elevation myocardial infarction (NSTEMI) adds one point for each of seven clinical predictors. The calculator evaluates age, coronary artery disease risk factors, known coronary artery disease, recent aspirin use, recurrent angina, ST-segment deviation, and elevated cardiac markers.
One point is assigned when each criterion is present:
| Predictor | Point | Criterion |
|---|---|---|
| Age | 1 | Age 65 years or older |
| Coronary artery disease risk factors | 1 | At least 3 of the following: diabetes, smoking, hypertension, hypercholesterolemia, or family history of premature coronary artery disease |
| Known coronary artery disease | 1 | Previous angiography showing at least 50% stenosis in a major coronary artery |
| Aspirin use | 1 | Aspirin used during the previous 7 days |
| Severe angina | 1 | At least 2 angina episodes during the preceding 24 hours |
| ST-segment deviation | 1 | ST-segment deviation of at least 0.5 mm on electrocardiography |
| Elevated cardiac markers | 1 | Troponin or CK-MB above the laboratory reference range |
The resulting score ranges from 0 to 7 points. The estimated 14-day risk is mapped to the score using the commonly reported TIMI event-risk estimates:
| TIMI score | Estimated 14-day risk | Risk category |
|---|---|---|
| 0–1 | 4.7% | Low |
| 2 | 8.3% | Low |
| 3 | 13.2% | Intermediate |
| 4 | 19.9% | Intermediate |
| 5 | 26.2% | High |
| 6–7 | 40.9% | High |
For example, a patient aged 68 years with three coronary artery disease risk factors, recurrent angina, ST-segment deviation, and elevated cardiac markers receives 6 points. The corresponding estimated 14-day risk is 40.9%. The score supports structured risk assessment but does not replace clinical evaluation, serial electrocardiography, biomarker testing, or guideline-directed management.
Practical Use Cases
Emergency physicians can use the calculator during the initial assessment of a patient with suspected unstable angina or NSTEMI to organize key history, electrocardiographic, and laboratory findings and identify the patient's short-term risk category.
Cardiologists can use the TIMI score as one component of a broader acute coronary syndrome evaluation when discussing monitoring intensity, invasive assessment, and treatment planning alongside clinical findings and current guidelines.
Emergency and cardiac nurses can use the seven-item checklist to confirm that relevant symptoms, aspirin exposure, electrocardiographic findings, and biomarker results have been documented before escalation or handoff.
Medical students and clinical trainees can use the calculator to practice applying the seven binary predictors and understand how additional risk features increase the estimated 14-day probability of death, myocardial infarction, or urgent target-vessel revascularization.
Clinical researchers and quality-improvement teams can use the standardized score to stratify patients in audits, registries, and educational cases, provided that the original score definitions and outcome population are preserved.
Accuracy and Limitations
The calculator applies the validated seven-predictor TIMI model and its commonly reported 14-day event-risk estimates, but the percentages are population-level estimates rather than an individual prognosis. Accuracy depends on correct classification of borderline findings, including age 65 years or older, at least three coronary artery disease risk factors, at least 0.5 mm of ST-segment deviation, and biomarkers above the laboratory reference range. The model was developed for patients with suspected unstable angina or NSTEMI and estimates death, myocardial infarction, or urgent target-vessel revascularization; it should not be applied as a standalone tool to diagnose acute coronary syndrome, assess STEMI, or determine treatment. It also does not include dynamic changes in symptoms, serial biomarkers, hemodynamic status, comorbid illness, or clinician interpretation of the electrocardiogram.
Quick Examples
Example #1: Low-Risk Presentation
Example of a younger patient with no known coronary artery disease, ischemic ECG changes, or elevated cardiac markers.
Example #2: Intermediate-Risk Presentation
Example of a middle-aged patient with several coronary risk factors and recurrent angina but no known coronary artery disease.
Example #3: High-Risk Presentation
Example of an older patient with established coronary artery disease, multiple risk factors, ischemic ECG findings, and elevated cardiac markers.
