Acute Coronary Syndromes (ACS) Flashcards
What are the 3 clinical subtypes?
Unstable angina (UA)
Non-ST segment elevation myocardial infarction (NSTEMI)
ST segment elevation myocardial infarction (STEMI)
What is it due to?
Sub-total = UA + NSTEMI
OR Total coronary artery occlusion (STEMI)
Complication of atherosclerosis
What is unstable angina characterised by?
Acceleration in frequency/severity of chest pain
New onset pain
Pain that occurs at rest
NO enzymatic evidence
Presence of an active pro-thrombotic surface at the site of plaque rupture
What is NSTEMI characterised by?
Unstable plaque rupture + thrombosis
Positive enzymatic evidence
Presence of persistent pro-thrombotic surface at site of plaque rupture
What is STEMI characterised by?
Unstable plaque rupture + thrombosis
Positive enzymatic evidence
Ischaemia-induced electrical instability
What is myocardial infarction (MI)?
Necrosis of myocardial tissue within 20-40 minutes of occlusion
Significant necrosis at 2-3 hours
What are the clinical features of pain of MI?
Acute central chest pain
Lasting >20 minutes
Often associated with nausea, sweatiness, dyspnoea, palpitations
What are the ECG changes for MI?
T wave inversion
ST segment elevation
Q wave development
What are the enzymatic changes for MI?
Troponin enzymes (T + I) released by heart tissues
= sign of necrosis
Why troponin T?
Can be released from cardiac muscle or skeletal muscle
Why troponin I?
Extremely specific for cardiac muscle = ideal marker for cardiac injury
What are the emerging biomarkers for MI?
Heart fatty acid-binding protein
B-type natriuretic peptide
Ischaemia-modified albumin
Co-peptin
What is the ECG change for STEMI?
ST elevation
What is the ECG change for NSTEMI?
ST depression
T inversion
What is the diagnostic criteria for MI?
Rise/fall in serum cardiac biomarkers
PLUS at least one…
Symptoms of ischaemia
ECG changes: new ST / T wave changes
Development of Q waves
Loss of myocardium on imaging
