HMMM
Handy Medical Math Machine

ACS / STEMI — Reperfusion Pathway

Source: ACC/AHA Guideline for Management of Acute Coronary Syndromes 2025 · Last reviewed: Jul 2026

1
Initial Action

12-lead ECG within 10 min of first medical contact. Aspirin loading (chewed), oxygen if SpO₂ <90%, nitrates/morphine per symptoms.

2
Decision

ST elevation meeting STEMI criteria?

No → NSTEMI/UA pathway (separate algorithm, not yet published). Yes → continue below.

3
Decision

Facility capable of primary PCI within target time?

Primary PCI

4a

Target door-to-balloon ≤90 min (direct presentation) or ≤120 min (requires transfer).

5a

DAPT: aspirin + ticagrelor/prasugrel (preferred over clopidogrel). Anticoagulant: UFH (or bivalirudin).

Fibrinolytic (if delay >120 min & onset <12 h)

4b

Target door-to-needle ≤30 min, followed by transfer for angiography (pharmaco-invasive approach).

5b

DAPT: aspirin + clopidogrel (mandatory on the fibrinolytic pathway). Anticoagulant: enoxaparin/fondaparinux.

Red Flag

Avoid prasugrel if history of stroke/TIA
Open Heparin Protocol
Calculate initial dose & titrate heparin (UFH) per the ACS/VTE protocol.
International general framework — adapt to local PCI availability, drugs, and referral network.