Cardiac arrest and ACLS
STEMI Algorithm
From the 12-lead to reperfusion
1 12-lead within 10 minutes of arrival
- ST elevation in two contiguous leads (1 mm, or 2 mm in V2–V3 by age and sex), or new LBBB with ischemic features or a posterior MI pattern
- Repeat every 15–30 minutes if the first is not diagnostic and symptoms continue
2 First medications
- Aspirin 162–325 mg chewed
- P2Y12 inhibitor per cath lab protocol
- Heparin bolus per protocol
- Nitroglycerin for pain if SBP over 90 and no RV infarct or PDE-5 use; oxygen only if SpO₂ under 90%
PCI-capable hospital → step 4No PCI within 120 minutes → step 5
3 Inferior MI: check the right ventricle
- Right-sided leads: ST elevation in V4R
- RV infarct: give fluids for hypotension; avoid nitrates, diuretics and morphine
4 Primary PCI
- Door-to-balloon 90 minutes or less (first medical contact to device 90 minutes, or 120 with transfer)
- Cardiogenic shock: emergent revascularization; consider a microaxial pump in selected patients
5 Fibrinolysis
- Within 12 hours of symptoms, door-to-needle 30 minutes or less
- Then transfer for angiography: urgently if reperfusion fails (under 50% ST resolution at 60–90 minutes)
Drugs in this algorithm
Related one-pagers
- ACS and STEMIACS spectrum and STEMI criteria: STEMI: Rises; never wait for it: New ST elevation
- Prehospital Stroke and STEMISTEMI: 12-lead and destination: STEMI: new J-point ST elevation in 2 contiguous leads, ≥1 mm (V2-V3: ≥2 mm men 40+, ≥2.5 mm men <40, ≥1.5 mm women), without LBBB or LVH
- Aortic Dissection and Hypertensive EmergencyAortic dissection: A vasodilator before the beta-blocker causes reflex tachycardia and raises aortic wall stress. No anticoagulants or thrombolytics: dissection can mimic an inferior STEMI.
- IABP ManagementIndications and contraindications: Guideline shift: IABP-SHOCK II showed no 30-day survival benefit in MI-related shock (39.7% vs 41.3% mortality). ACC/AHA (2025) and ESC advise against routine IABP there unless a mechanical complication exists; selected STEMI shock may get a microaxial flow pump instead. Older items may still call shock the classic indication.
More cardiac arrest and acls algorithms
- Adult Cardiac Arrest
- Bradycardia With a Pulse
- Tachycardia With a Pulse
- Arrest After Cardiac Surgery
- VT Storm
- Flash Pulmonary Edema (SCAPE)
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