Acute coronary syndromes Flashcards
central mechanism of ACS is
a ruptured plaque
which type of plaques to ruptures occur?
in soft plaques with thin caps
when platelets are exposed to collagen they
are activated
form a thrombus and may have ischemia as a result
A sudden change in the lumen of a plaque can lead to
unstable angina
rapid necrosis of an entire region supplied by an occluded artery leads to
an MI
most often an ST elevation will have
a Q-wave
If you have chest pain for >20mins to hours it is suggestive of
an infarct
If angina is new, accelerated, crescendo, rest, or post-MI
concern that it is unstable
ECG findings of Normal, T inversion or ST depression are indicative of
Unstable angina or Non-STEMI
ECG findings of ST elevation or LBBB
STEMI
ST elevations in V1-V4 suggest
Anterior wall, LAD
ST elevations in 2,3 and aVF
Inferior wall, RCA
ST elevations in v5-v6
Lateral wall, Circumflex
How long until cardiac enzymes are elevated in necrosis
4-6 hours
main cardiac enzymes to measure
troponin T and I
CK-MB
If you have UNSTABLE angina with abnormal troponin
suspect a Non-STEMI
Peak and drop off of cardiac troponin if reperfusion occurs
within 1-2 days it will peak, and then drop
High sensitivity troponin assay has
High sensitivity but Low specificity
therapy for unstable angina
rest
O2
pain control - nitroglycerine and morphine
Therapy that improves survival in unstable angina
- Heparin
- anti-platelet
- beta block
- statin/acei
If you have an occluded artery, how long until 90% of the myocardium is infarcted
3 hours
STEMI is
angina lasting for 30 mins to hours
Mimics of MI
PE
Pericarditis
Aortic dissection
Heparin is contraindicated in
pericarditis
aortic dissection
