Acute Coronary Syndromes Flashcards
What change/event in the atherothrombotic process can lead to ACS (MI, stroke, unstable angina)?
Plaque rupture consequently occluding critical areas (coronary artery)
Describe chronic/stable angina
Fixed stenosis due to atheroma limits blood flow
Pain on exertion, relieved by rest/GTN spray
What are the 3 (main) acute coronary syndromes?
Unstable angina
NSTEMI
STEMI
What factors favour plaque rupture?
Thin fibrous cap
Sudden intraluminal pressure changes
High lipid content of plaque
How does plaque rupture affect the endothelium in terms of platelets?
Blood is exposed to sites it doesn’t normally see
Platelets adhere to damaged areas through vWF and collectively form hemostatic plug
How does unstable angina differ from stable angina?
Pain caused by less and less exertion, in some cases eventually at rest
GTN becoming less effective
How does angina differ from acute MI?
Shorter (10 mins vs. 30 mins)
Pain on exertion (vs. rest)
GTN relief (vs. no relief)
What are typical ECG changes that occur in STEMI?
ST elevation
T wave inversion
Q wave formation
Why are Q waves “useful”?
Signal that there has been a previous MI
What characteristics must the ST elevation have in order to diagnose STEMI?
> 1mm STE in 2+ adjacent limb leads
>2mm STE in 2+ contiguous precordial leads
Which leads show STE in an inferior MI?
II, III, aVF
Which leads show STE in an anterior MI?
V1-V6
Which leads show STE in an anterolateral MI?
I, aVL, V1-V6
Which leads show STE in an anteroseptal MI?
V1-V4
Which two proteins are used for diagnosing MI?
Troponin T or I
CK enzyme