TIMI NSTEMI Score Calculator

TIMI Risk Score for Unstable Angina and NSTEMI

The TIMI Risk Score for Unstable Angina (UA) and Non-ST-Elevation Myocardial Infarction (NSTEMI) is an evidence-based clinical risk stratification algorithm developed by Dr. Elliott Antman and colleagues (JAMA 2000). Derived from the TIMI 11B and ESSENCE clinical trials, it calculates the 14-day composite risk of all-cause mortality, recurrent myocardial infarction, or severe recurrent ischemia requiring urgent coronary revascularization.

The Seven Prognostic Variables

Each of the following binary criteria is assigned 1 point (total score ranges from 0 to 7):

• Age $\ge 65$ years: Advanced age increases coronary complexity and adverse cardiovascular events.
• $\ge 3$ CAD Risk Factors: Documented family history of premature CAD, hypertension, hypercholesterolemia, diabetes mellitus, or active tobacco smoking.
• Known Prior CAD: Documented coronary artery stenosis $\ge 50\%$ on prior angiography.
• Aspirin Use in Past 7 Days: Reflects acute coronary plaque rupture or progression despite antiplatelet therapy.
• Severe Angina: At least 2 distinct episodes of rest or severe angina in the preceding 24 hours.
• ST-Segment Deviation $\ge 0.5\text{ mm}$: Significant transient or persistent ST depression or elevation on presenting 12-lead ECG.
• Positive Cardiac Biomarkers: Elevated baseline cardiac troponin (I or T) or CK-MB above the upper limit of normal.

14-Day Risk Stratification & Clinical Strategy

The cumulative score predicts 14-day adverse composite endpoints:

• Score 0 to 1 (4.7% risk): Low risk. Non-invasive observation, stress testing, or outpatient management.
• Score 2 (8.3% risk): Low risk. Observation and selective invasive evaluation based on symptoms.
• Score 3 (13.2% risk): Intermediate risk. Early invasive strategy (diagnostic catheterization within 24 to 72 hours).
• Score 4 (19.9% risk): Intermediate risk. Inpatient invasive strategy with dual antiplatelet therapy.
• Score 5 (26.2% risk): High risk. Urgent coronary angiography and intensive antithrombotic therapy.
• Score 6 to 7 (40.9% risk): High risk. High-priority catheterization and potential surgical or percutaneous revascularization.

Related Cardiovascular Tools

Complement your cardiac risk assessments with our related calculators:

• TIMI STEMI Score Calculator for ST-elevation myocardial infarction mortality.
• Revised Cardiac Risk Index Calculator for non-cardiac surgery perioperative risk.
• Shock Index Calculator for rapid hemodynamic instability screening.