Acute Coronary Syndrome Flashcards
(32 cards)
Define acute coronary syndrome
symptoms from underlying acute myocardial ischemia
Causes of ACS
1) atherosclerotic plaque rupture + thrombus = MOST COMMON
2) coronary embolism
3) congenital
4) coronary trauma/aneurysm
5) cocaine (spasm)
6) incr blood viscosity
7) spotaneous coronary dissection
8) incr myocardial O2 demand
partial occlusion
decr blood flow in artery distal to occlusion
decr O2 supply to myocardium
ischemia
complete occlusion
no blood flow and O2 to entire myocardium supplied by artery = ischemia
Pathophys of ACS
1) inflamm + risk factors incr atherosclerosis
2) dysfunctional endothelium
3) inflamm mediators weaken atherosclerotic fibrous cap
4) if cap bursts, thrombogenic tissue factor released –> platelet aggreg
5) dysfunctional endo + coag + PLT aggreg = coronary thrombosis
define STEMI
1) complete coronary vessel occlusion
what is a complete coronary vessel occlusion called
STEMI
define NSTEMI
partial coronary vessel occlusion with myocardial necrosis
what is a partial coronary vessel occlusion with myocardial necrosis
NSTEMI
define unstable angina
partial coronary vessel occlusion and ESCALATING SX without myocardial necrosis
don’t need troponin elev
what is partial coronary occlusion WIthout MYOCARDIAL NECROSIS
unstable angina
define transmural ischemia
spans entire thickness of myocardium assoc with COMPLETE coronary OCCLUSION
ST ELEVATION
define subendocardial ischemia
involves innermost layer of myocardium due to PARTIAL coronary occlusion
ST DEPRESSION
if ischemia is prolonged, ____
results in myocyte death + tissue necrosis (STEMI or NSTEMI)
ecg changes of STEMI and NSTEMI
STEMI = ST elevation
NSTEMI = ST depression
___ is very sensitive and specific for myocardium
Cardiac troponin
Describe angina
discomfort due to myocadial ischemia
chest pain/pressure/tightness
symptoms of angina
1) substernal chest pain/tightness
or
2) left arm pain, SOB, N/V, weakness,
Stable angina define
when incr demand for myocardial oxygen in REPRODUCIBLE fashion
Unstable angina define
no myocyte death but ischemia is occurring
new onset OR
increased duration, freq, intensity of discomfort with less exertion
or
less provocation/discomfort at rest
which of the angina’s is on the spectrum of ACS?
UNSTABLE ANGINA
Treatment of ACS (2 golas)
1) relieve ischemia
- open artery or prevent further occlusion
- reduce myocardial O2 demand
2) prevent adverse outcomes
how to treat STEMI
1) if artery occluded, open !!!
primary PCI
if >90 min, use fibrinolytics and transfer
if >90 + heme/BP stable, use oral beta blockers/nitrates (reduce LV filling) to decr myocardial O2 demand
how to treat NSTEMI/unstable angina
1) artery partially occlude–> give anticoag + anti platelet to STOP PROPAGATION OF CLOT TO BECOME STEMI
reduce myocardial O2 demand using beta blockers, nitrates
or
cath lab for PCI
