Cardiovascular18 UKMLA questions
Myocardial Infarction — UKMLA Revision Notes
Myocardial infarction (MI) results from prolonged ischaemia causing irreversible myocardial cell death, most commonly due to rupture of an atherosclerotic plaque with superimposed thrombosis. Classified as STEMI or NSTEMI based on ECG findings.
Key Facts
- STEMI: ST elevation ≥1mm in ≥2 contiguous limb leads, or ≥2mm in chest leads
- NSTEMI: troponin rise without persistent ST elevation
- Troponin I and T are the preferred biomarkers (rise 3–6 hours after onset)
- Primary PCI is the preferred reperfusion strategy for STEMI if available within 120 minutes
- Dual antiplatelet therapy (aspirin + P2Y12 inhibitor) is standard post-MI
Investigations
- 12-lead ECG: ST changes, new LBBB, T-wave inversions
- Troponin I/T: serial measurements at 0 and 3 hours
- FBC, U&E, LFTs, lipid profile, glucose
- Echocardiogram: assess LV function, wall motion abnormalities
- Coronary angiography: definitive investigation and treatment
Management
- STEMI: primary PCI within 120 minutes of first medical contact (NICE NG185)
- Aspirin 300mg loading dose + ticagrelor 180mg (or prasugrel/clopidogrel)
- Anticoagulation: unfractionated heparin or fondaparinux
- Beta-blocker, ACE inhibitor, statin: commence within 24 hours
- NSTEMI: risk-stratify with GRACE score; early invasive strategy if high risk
NICE Guideline: NICE NG185 — Acute coronary syndromes (2020)
Related UKMLA Conditions
AnginaHeart FailureAtrial FibrillationCardiogenic Shock