ST-elevation myocardial infarction

Red Flags

ST elevation ≥1 mm in two contiguous leads or new LBBB with chest pain — immediate reperfusion. First medical contact to PCI ≤90 min, to fibrinolysis ≤30 min^[1]
Cardiogenic shock complicating STEMI (SBP <90, signs of hypoperfusion) — emergent revascularisation regardless of time from symptom onset^[1]
Mechanical complication (acute mitral regurgitation, ventricular septal rupture, free-wall rupture) — emergent surgical consult and inotropic/MCS support^[1]
Posterior STEMI (ST depression V1–V3 with ST elevation V7–V9) — easily missed; obtain posterior leads^[1]

Primary percutaneous coronary intervention (pPCI)^[1]
Preferred reperfusion when achievable within 90 min of first medical contact (120 min if transfer required). Door-to-balloon time ≤90 min for direct presentation; FMC-to-device ≤120 min for transfer
Fibrinolytic therapy^[1]
Tenecteplase weight-based bolus when pPCI unavailable within 120 min FMC. Half-dose for age ≥75. Transfer to PCI-capable centre afterward for routine angiography within 2–24 h

Drug	Class	Adult	Paediatric	Notes
Aspirin^[1]	Antiplatelet (loading)	162–325 mg chewed and swallowed at first medical contact	—	Followed by 75–100 mg once daily lifelong
Ticagrelor^[1]	P2Y12 inhibitor (loading)	180 mg PO loading then 90 mg BD for 12 months	—	Preferred over clopidogrel in PCI-treated STEMI; prasugrel 60 mg load then 10 mg daily is alternative if no prior stroke/TIA
Unfractionated heparin^[1]	Parenteral anticoagulant	60 U/kg IV bolus (max 4000 U) then 12 U/kg/h infusion (max 1000 U/h)	—	During PCI; titrate to ACT. Bivalirudin is alternative
Atorvastatin^[1]	High-intensity statin	80 mg PO once daily	—	Initiate during admission regardless of baseline LDL-C; LDL-C goal <55 mg/dL
Metoprolol tartrate^[1]	Beta-blocker	25–50 mg PO BD initially, transition to long-acting succinate 25–200 mg once daily	—	Within 24 h if no contraindication (heart failure, shock, heart block)
Ramipril^[1]	ACE inhibitor	1.25–2.5 mg PO BD initially, titrate to 5 mg BD	—	Within 24 h, especially with anterior infarct, LVEF <40%, heart failure, or diabetes

Aspirin^[1]

Antiplatelet (loading)

Followed by 75–100 mg once daily lifelong

Ticagrelor^[1]

P2Y12 inhibitor (loading)

Preferred over clopidogrel in PCI-treated STEMI; prasugrel 60 mg load then 10 mg daily is alternative if no prior stroke/TIA

Unfractionated heparin^[1]

Parenteral anticoagulant

During PCI; titrate to ACT. Bivalirudin is alternative

Atorvastatin^[1]

High-intensity statin

Initiate during admission regardless of baseline LDL-C; LDL-C goal <55 mg/dL

Metoprolol tartrate^[1]

Beta-blocker

Adult: 25–50 mg PO BD initially, transition to long-acting succinate 25–200 mg once daily
Paediatric: —

Within 24 h if no contraindication (heart failure, shock, heart block)

Ramipril^[1]

ACE inhibitor

Within 24 h, especially with anterior infarct, LVEF <40%, heart failure, or diabetes

Take dual antiplatelet therapy (aspirin + ticagrelor or clopidogrel) every day for 12 months without interruption — stopping early sharply raises the risk of stent clot^[1]
Recurrence of chest pain at rest or with exertion at any time after discharge — call emergency services immediately^[1]
Attend cardiac rehabilitation — supervised exercise after a heart attack reduces death and re-admission by 20–30%^[1]

Diagnostic ECG for STEMI in any settingActivate cath lab; transfer to PCI-capable centre if not on-site (target FMC-to-device ≤120 min)^[1]
Cardiogenic shock or mechanical complicationHeart team plus mechanical circulatory support consideration (intra-aortic balloon pump, Impella, VA-ECMO)^[1]
Post-STEMI LVEF ≤35% at 40 days despite optimal medical therapyCardiology for primary prevention ICD evaluation^[1]

Recognition, reperfusion, and post-reperfusion management of ST-elevation myocardial infarction (STEMI) in adults.

1.2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes (2025)