Myocardial Infarction Flashcards
Common causes of STEMI
Coronary artery disease:
Atherosclerosis with plaque fissuring
Rupture and thrombus formation
3 categories of acute coronary syndrome (ACS)
STEMI: ECG shows persistent ST elevation in 2 or more leads.
NSTEMI: ECG doesn’t show STEMI but there is elevated cardiac biomarkers.
Unstable angina: non-specific ischaemic changes but no elevated biomarkers
Name 5 risk factors for MI
Smoking Hypertension Diabetes Obesity Metabolic syndrome Dyslipidaemia Renal insufficiency FHx of premature CAD (male <55, female<65) Cocaine use
Signs and symptoms of MI
Chest pain Dyspnoea (SOB) Pallor Diaphoresis (excessive abnormal sweating) Nausea/Vomiting Dizziness/light headed Tachycardia Additional heart sounds
investigations for MI
ECG: look for STEMI or ischaemic changes. ST depression in 2 or more leads in V1-4 should be considered as STEMI
Cardiac biomarkers (CK, CK-MB, Troponin) Troponin elevated 4-6 hrs after trauma last 10 days
Portable CXR but should not delay treatment (exclude other causes of chest pain and asses current cardiac function) Widened mediastinum (aortic dissection)
Coronary angiogram (identify occlusion)
After treatment ECHO
Which leads show an inferior MI
Leads II, III, aVF
MI treatment if there’s access to PCI within 90 minutes
Percutaneous coronary intervention
Anticoagulation (e.g. Abciximab and enoxaparin)
Aspirin and PY
Which leads show a lateral MI
I, aVL, V5-V6
Which leads show an anterior MI
v1-6 predominantly v1, v2
What does v3 and v4 show?
anterior wall
Which leads will show a possible RCA occlusion
Inferior: II. III, aVF
Posterior: Tall R in V1 (also v2, v3)
Horizontal ST depression
upright T waves
Which leads show LAD occlusion
v1, v2. -anteroseptal
v3 & v4 (distal) - anteroapical
Which leads show Cx occlusion
I, aVL, v5, v6
Which leads show proximal LCA occlusion
I, aVL, v2, v6
