This TIMI score calculator computes the TIMI Risk Score for unstable angina / NSTEMI — seven yes/no predictors whose sum maps, in the original Antman trial data, to the 14-day risk of death, new or recurrent MI, or severe ischemia requiring urgent revascularization. Where HEART sorts undifferentiated chest pain, TIMI starts after ACS is diagnosed and asks how dangerous the next two weeks are.

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Seven Predictors, Deliberately Unweighted

The TIMI Risk Score (Antman et al., JAMA 2000) was distilled from the TIMI 11B and ESSENCE trial populations — patients with confirmed unstable angina or NSTEMI — by finding the baseline variables that independently predicted the 14-day composite of death, MI and urgent revascularization. Seven survived multivariate analysis, and the authors made a design choice that explains the score’s longevity: each counts one point, no coefficients, no calculator required at 3 a.m. Age ≥ 65, ≥ 3 conventional risk factors, documented CAD with ≥ 50% stenosis, aspirin already taken in the last week (a marker of breakthrough symptoms despite therapy), two or more anginal episodes in 24 hours, ST deviation of at least 0.5 mm, and a positive cardiac marker. The derivation cohorts’ event rates then stair-step with beautiful menace: 4.7% at scores 0–1 up to 40.9% at 6–7 — nearly a tenfold gradient from seven coin flips.

The score earned its keep guiding therapy, not just prognosis: in the trial analyses, the benefit of enoxaparin over unfractionated heparin and of an early invasive strategy grew with the score, being clearest at ≥ 3. That treatment-linked gradient is why TIMI persists in guidelines long after flashier models appeared — a score that changes management at a visible threshold is clinically alive. (The GRACE score is more precise for mortality prediction across ACS, at the price of many more inputs; TIMI’s seven boxes remain the bedside instrument.) Note the separate TIMI score for STEMI — different variables, different table; this page is the UA/NSTEMI instrument, named so on purpose.

Worked Example

  • Defaults: a patient with ≥ 2 recent anginal episodes, ST deviation and a positive troponin — but under 65, fewer risk factors, no known CAD, no recent aspirin: score 3, 14-day composite risk ≈ 13.2% — squarely at the threshold where early invasive management showed its benefit in the defining trials.
  • The low end: a 58-year-old with atypical-but-real NSTEMI by troponin alone scores 1 (marker only) → 4.7% — “low” only relative to a population that all has ACS; discharge thinking does not apply anywhere on this scale.
  • The full house: 71 years old, diabetic hypertensive smoker, known CAD, symptoms breaking through aspirin, ST depression, positive marker = 7 → ≈ 40.9%: two in five such patients met the composite endpoint within two weeks in the derivation era — the score at its most eloquent.

TIMI Discipline

  • Population discipline: TIMI applies to diagnosed UA/NSTEMI. Applying it to undifferentiated chest pain to justify discharge is the classic misuse — its floor (4.7%) is an event rate no ED accepts for rule-out.
  • “Known CAD” means documented ≥ 50% stenosis; presumed disease doesn’t count. Likewise the aspirin item means actually taken within 7 days, not prescribed.
  • Event rates are era-stamped: derivation patients predate high-sensitivity troponin, potent P2Y12 inhibitors and radial-access early-PCI defaults; modern absolute rates at each score run lower, though the gradient and the ≥ 3 decision threshold remain the taught landmarks.
  • The score is static by design (presentation variables) — clinical course (recurrent pain, dynamic ECG, hemodynamics) overrides it in either direction, as it should.

Related Tools

Frequently Asked Questions

How is the TIMI (UA/NSTEMI) score calculated?

One point each for: age ≥ 65; ≥ 3 CAD risk factors; known coronary stenosis ≥ 50%; aspirin use within 7 days; ≥ 2 anginal episodes in 24 hours; ST deviation ≥ 0.5 mm; and positive cardiac markers. The sum (0–7) maps to 14-day composite risk (death/MI/urgent revascularization) in Antman 2000: 0–1 → 4.7%, 2 → 8.3%, 3 → 13.2%, 4 → 19.9%, 5 → 26.2%, 6–7 → 40.9%. This calculator sums and maps exactly that table.

What does the TIMI score predict?

The 14-day risk of the composite endpoint — all-cause mortality, new or recurrent myocardial infarction, or severe recurrent ischemia requiring urgent revascularization — in patients with unstable angina or NSTEMI. It’s a short-horizon, treatment-relevant prognosis: historically, scores ≥ 3 identified patients who benefited most from enoxaparin and early invasive strategy, which is the clinical action the score exists to trigger.

TIMI vs HEART — what’s the difference?

Population and purpose. HEART is for undifferentiated ED chest pain and specializes in finding the low-risk patients who can go home. TIMI (UA/NSTEMI) is for patients already diagnosed with ACS and stratifies how aggressively to treat in the following days. A TIMI score of 0–1 still means ~4.7% events in 14 days among confirmed-ACS patients — far too risky for discharge decisions — while HEART would never be applied after the ACS diagnosis is made. The two calculators are sequential doors on the chest-pain pathway, not alternatives.

Is there a different TIMI score for STEMI?

Yes — the TIMI Risk Score for STEMI (Morrow et al.) uses different variables (age bands, blood pressure, heart rate, Killip class, anterior location/LBBB, diabetes/ hypertension/angina history, weight, and time to treatment) to predict 30-day mortality after ST-elevation MI. It is a separate instrument with its own table; this page implements only the UA/NSTEMI score, which is the one most often meant by “TIMI score” in ED and cardiology-ward usage. Mixing the two tables is a real and dangerous clerical error — labels matter.

Why does recent aspirin use count as a risk point?

Because in the derivation data, patients whose symptoms occurred despite aspirin already on board fared worse — plausibly a marker of more aggressive plaque activity or aspirin non-response (“breakthrough” events). It’s the score’s most counterintuitive item and the one most often mis-scored (prescribed ≠ taken; taken 10 days ago ≠ within 7). The item rewards careful history-taking, not medication shaming — nobody should stop aspirin to improve a score.

Are the 2000 event rates still valid today?

The ranking and gradient remain robust and guideline-endorsed; the absolute percentages have drifted downward with modern therapy (high-sensitivity troponins also reclassify the marker item’s population) and contemporary registries generally show lower event rates at each score. Use the table as this calculator presents it — the published Antman benchmarks — while understanding that a modern ≥ 3 score still triggers the same escalation conversation, because the relative benefit of early invasive strategy in higher scores has persisted across eras.

What score warrants early invasive strategy?

The trial-era signal — benefit of early angiography/invasive management and of enoxaparin concentrated at TIMI ≥ 3 — still anchors teaching and many pathways, integrated with GRACE assessment, hemodynamics, ECG dynamics and patient factors in current guidelines. The score informs the urgency conversation; it doesn’t schedule the cath lab by itself. Documented score + trajectory + guideline pathway remains the complete clinical sentence.

Is this TIMI score calculator free?

Yes — free and instant, reproducing the published Antman criteria and rates as an educational aid; management decisions belong to the treating team.