ICU · Cardiovascular
Acute coronary syndromes (STEMI, NSTEMI, unstable angina)
Also known as ST-elevation myocardial infarction (STEMI) · Non-ST elevation MI (NSTEMI) · Unstable angina (UA) · Primary PCI · Door-to-balloon time · GRACE risk score
Exam-focused guide to acute coronary syndromes in intensive care: STEMI and NSTEACS diagnosis, ECG and troponin, reperfusion strategy, antiplatelet and anticoagulant therapy, risk scores, cardiogenic shock and secondary prevention.
Checked against its sources on 23 Oct 2026
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Target exams
Red flags
- STEMI/ACOMI within 12 h of symptom onset: emergency reperfusion; give fibrinolysis if primary PCI cannot be delivered within 120 min of first medical contact
- ACS with cardiogenic shock: PCI of the infarct-related artery only; routine intra-aortic balloon pump or VA-ECMO not recommended
- Record and assess an ECG for acute coronary occlusion within 10 min of first clinical contact
- SpO2 of 90% or more: oxygen therapy is not required
Meet the patient
A 58-year-old smoker arrives in your resuscitation bay at 3am with an hour of central chest pressure radiating to both arms. He is sweating and breathless, and the first ECG shows ST elevation in II, III and aVF. The nearest PCI centre is 45 minutes away by road. [1]
Hold two questions and everything below slots into place. Is the artery occluded? The ECG, recorded and assessed within 10 min of first clinical contact, answers that. Can it be opened in time? The 120-minute threshold from first medical contact decides between primary PCI and fibrinolysis. [1]
References24ShowHide
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- [2]Wallentin L, Becker RC, Budaj A, et al. Ticagrelor versus clopidogrel in patients with acute coronary syndromes. The New England journal of medicine, 2009.PMID 19717846
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- [12]Van de Werf F, Ristić AD, Averkov OV, et al. STREAM-2: Half-Dose Tenecteplase or Primary Percutaneous Coronary Intervention in Older Patients With ST-Segment-Elevation Myocardial Infarction: A Randomized, Open-Label Trial. Circulation, 2023.PMID 37439219
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- [15]Hochman JS, Sleeper LA, Webb JG, et al. Early revascularization in acute myocardial infarction complicated by cardiogenic shock. SHOCK Investigators. Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock. The New England journal of medicine, 1999.PMID 10460813
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- [17]Thiele H, Zeymer U, Neumann FJ, et al. Intraaortic balloon support for myocardial infarction with cardiogenic shock. The New England journal of medicine, 2012.PMID 22920912
- [18]Møller JE, Engstrøm T, Jensen LO, et al. Microaxial Flow Pump or Standard Care in Infarct-Related Cardiogenic Shock. The New England journal of medicine, 2024.PMID 38587239
- [19]Bonaca MP, Bhatt DL, Cohen M, et al. Long-term use of ticagrelor in patients with prior myocardial infarction. The New England journal of medicine, 2015.PMID 25773268
- [20]Dewilde WJ, Oirbans T, Verheugt FW, et al. Use of clopidogrel with or without aspirin in patients taking oral anticoagulant therapy and undergoing percutaneous coronary intervention: an open-label, randomised, controlled trial. Lancet (London, England), 2013.PMID 23415013
- [21]Murphy SA, Cannon CP, Wiviott SD, et al. Reduction in recurrent cardiovascular events with intensive lipid-lowering statin therapy compared with moderate lipid-lowering statin therapy after acute coronary syndromes from the PROVE IT-TIMI 22 (Pravastatin or Atorvastatin Evaluation and Infection Therapy-Thrombolysis In Myocardial Infarction 22) trial. Journal of the American College of Cardiology, 2009.PMID 20082923
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