Angina, ACS and MI Flashcards
(57 cards)
what is the main difference between stable and unstable angina?
stable predictable, comes on during exercise and relieved by rest
unstable can come on at any point (including rest) and can’t always be relieved by rest
what are the conditions that make up acute coronary syndromes?
unstable angina
NSTEMI
STEMI
what are some of the causes of acute coronary syndromes?
atherosclerosis vasospasm cocaine emboli coronary dissection coronary vasculitis
what investigations should be done to diagnose an ACD?
HR, BP
ECG
blood test for markers (troponin, CK)
chest xray
if troponin levels are elevated if a patient presents with chest pain, what can that be a sign of?
STEMI
NSTEMI
if troponin levels are not elevated if a patient presents with chest pain, what can that be a sign of?
unstable angina
stable angina
non-cardiac reasons
what other conditions could show elevated troponin levels?
pulmonary embolism
sepsis
kidney failure
subarachnoid hemorrage
where on an ECG would a lateral MI show abnormalities?
SLL1
aVF
might involve the Cx
where on an ECG would an inferior MI show abnormalities, and which vessel would it normally involve?
aVF
SLL2
SLL3
might involve the RCA
where on an ECG would an anterior MI show abnormalities, and which vessel would normally be involved?
V1-V4
might involve the LAD
what is the pharmacological treatment management for ACS?
morphine (pain relief) oxygen if sats low nitrates IV aspirin \+ clopidogrel/ticagrelor/prasugrel fondaparinux/heparin beta blockers (when pt stable) statins ACEIs
what are more invasive treatment options for ACS/MI?
PCI
CABG
what is the main protocol for treating a STEMI?
PCI within two hours of event
if no PCI facility available (fast enough), thrombolysis
what are the thrombolysis options for MI and their characteristics?
tenecteplase, alteplase: fibrin-specific
streptokinase: older drug, not fibrin-specific
what is the mechanism of action of aspirin?
it stops production of Thromboxane A2 at the beginning of the platelet activation process
what is the mechanism of action of clopidogrel, and what are its pharmacological properties?
prodrug - activated in liver
it stops the ADP receptor, which in turn acts on the GP IIb/IIIa receptor
what is the difference between clopidogrel and ticagrelor?
clopidogrel is a pro-drug, some patients don’t metabolise it
ticagrelor is not a prodrug
what are some signs/symptoms of ACS/MI?
variable, especially with NSTEMI crushing chest pain/discomfort pain may radiate to neck/arms cold/clammy/sweaty SoB nausea/vomiting collapse
which layers of the heart muscle are affected in NSTEMI and STEMI?
NSTEMI - endocardial layer = mural/endocardial MI
STEMI - all three layers = transmural MI
what are the possible changes on an ECG during and after a STEMI?
ST elevation
hyperacute T waves
Q waves after a few days (dead tissue)
what are the possible changes on an ECG during and after a NSTEMI?
ST depression
inverted T wave
normally no Q waves
how can a posterior MI be diagnosed?
by putting V leads on the patient’s back in opposite places as V1/V2
what is used to support the diagnosis of an MI?
biomarker presence (CK, troponin) + ECG changes, symptoms, autopsy changes, other imaging evidence of cardiac damage
what is the pathological difference between an NSTEMI and a STEMI?
STEMI - complete occlusion of a vessel
NSTEMI - severe narrowing but not complete obstruction of vessel
