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
ECG findings in an MI
elevation in 2 contiguous leads in the same territory
a new LBBB is equivalent to
an ST elevation
what is the main goal of treatment for STEMI?
REPERFUSION - thrombolytics
Main types of reperfusion for STEMI
- coronary angio
- thrombolytic
what determines post-MI prognosis
- Age and left ventricular function
- residual disease
- an arrythmia
- comorbid disease
