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
- Shock Types at a GlanceCardiogenic shock: LV, RV, SCAI and MCS escalation: RV shock follows RV infarct (inferior STEMI, ST elevation in V4R), PE, ARDS, pulmonary hypertension and LVAD implantation. The dilated RV pushes the septum into the LV, so LV filling falls even with normal LV muscle. Give fluid until CVP is about 10–15 mm Hg, then stop; keep AV synchrony (pace heart block); avoid hypoxemia, hypercapnia, acidosis
- Implanted Cardiac Devices: Pacemakers, ICDs and Wearable DefibrillatorsPacemaker code, guideline sources and exam points: Exams like the WCD as the bridge: an EF of 25% three days after a STEMI is too early for an ICD, but the risk of sudden death is real now.
- Lab Values to KnowDiabetes, lipids, liver, heart: A1C 5.7–6.4%: prediabetes; it reflects about 3 months, skewed by anemia, kidney failure and transfusion. Troponin up without ischemia is injury, not MI. hs-troponin is serial (often 0 and 1–2 h); STEMI does not wait for it.
- Rhythm GalleryST and T changes: STEMI: new ST elevation in 2 or more contiguous leads (1 mm or more; higher in V2–V3). 12-lead within 10 min of first contact; door-to-PCI goal 90 min or less.
More cardiac arrest and acls algorithms
Practice free in your browser2,150+ exam-style questions with rationales. No account, no ads. Also free on the App Store and Google Play.
For education and exam preparation only. Follow your institution’s protocols. Study aid with typical adult values; follow your institution's protocols and current AHA guidelines.