Chest pain with ST elevation: activate the primary PCI pathway immediately. Give aspirin 300 mg and a second antiplatelet per your local STEMI protocol unless contraindicated.
Red flags
- Central crushing pain radiating to jaw or arm
- Diaphoresis, nausea, haemodynamic instability
- New ST elevation, LBBB, or posterior MI signs (ST depression V1 to V3)
- Dynamic high-sensitivity troponin rise
Initial meds (typical)
- Aspirin 300 mg chewed
- P2Y12 inhibitor (ticagrelor or prasugrel) per pathway if not high bleeding risk
- Anticoagulation per PCI pathway
- GTN if BP allows; avoid in RV infarction or hypotension
Low-risk chest pain
- Normal serial troponin and ECG
- Consider other causes
- Outpatient assessment
NSTEMI / unstable angina
- Troponin rise or ischaemic ECG
- GRACE risk stratification
- Angiography within 72 h if high risk
STEMI
- ST elevation or new LBBB
- Primary PCI within 120 min
- Aspirin plus a P2Y12 inhibitor now
ACS pathway
1
1. Assess
12-lead ECG within 10 minutes and repeat if ongoing pain. History, risk factors, exam. Give oxygen only if SpO2 below 94%. Morphine sparingly.
12-lead ECG within 10 minutes and repeat if ongoing pain. History, risk factors, exam. Give oxygen only if SpO2 below 94%. Morphine sparingly.
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2
2. STEMI
Primary PCI if presentation within 12 h and PCI deliverable within 120 min of when thrombolysis could be given. Otherwise thrombolysis, then transfer for angiography.
Primary PCI if presentation within 12 h and PCI deliverable within 120 min of when thrombolysis could be given. Otherwise thrombolysis, then transfer for angiography.
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3
3. NSTEMI / unstable angina
Risk stratify with GRACE. Fondaparinux if not for immediate angiography. Early invasive angiography (within 72 h) if intermediate or high risk.
Risk stratify with GRACE. Fondaparinux if not for immediate angiography. Early invasive angiography (within 72 h) if intermediate or high risk.
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4
4. Aftercare
Dual antiplatelet, high-intensity statin, ACE inhibitor, beta-blocker, echo for LV function. Cardiac rehab and secondary prevention.
Dual antiplatelet, high-intensity statin, ACE inhibitor, beta-blocker, echo for LV function. Cardiac rehab and secondary prevention.
| Scenario | Action |
|---|---|
| PCI within 120 min of when thrombolysis could be given | Primary PCI |
| PCI not available in that window, within 12 h of onset | Thrombolysis then transfer for angiography |
| Presenting after 12 h | Discuss with cardiology; angiography if ongoing ischaemia |
Right ventricular infarct
- Inferior STEMI: do right-sided leads (V4R)
- Preload-dependent: give fluids, avoid GTN and opioids
- Hypotension with clear chest
Pitfalls
- Missing posterior or right ventricular MI
- Delaying aspirin or the PCI call
- GTN or opioids in RV infarction with hypotension
- Routine high-flow oxygen when saturations are normal
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026