Flashcards in MI Deck (90):
What's stable angina?
chest/arm discomfort/pain that's reproducibly associated with physical exertion/stress and is relieved within 5-10 minutes by rest or SL nitroglycerin
What's unstable angina?
angina pectoris/equivalent ischemic discomfort associated with one of the following 3:
occurs at rest usually lasting >10 min
is severe and of new onset
occurs with a crescendo pattern
What's an MI?
clinical features of unstable angina + myocardial necrosis (increased cardiac biomarkers)
What are modifiable risk factors of MI?
What are non-modifiable risk factors of MI?
Plaque with fibrous cap-->cap ruptures-->blood clot forms around the rupture, blocking the artery
What's a red thrombi?
RBC's in fibrin mesh
What's the consistency of a red thrombus?
What's the mechanism of a red thrombus?
Where are red thrombi located?
What are examples of red thrombi?
clot on mechanical heart valved
How do you treat red thrombi?
What's the composition of a white thrombus?
platelets in fibrin mesh
what's the consistency of a white thrombus?
What's the mechanism of white thrombi?
Where are white thrombi located?
What are examples of white thrombi?
peripheral arterial disease
coronary artery disease
How do you treat a white thrombus?
What are Q waves indicative of?
Q waves are indicative of a prior MI event
What are the two main cardiac biomarkers?
Describe troponin T
peaks in 12-20 hours
check with lab for threshold value
remains elevated for up to 10 days
Describe creatinine kinase myocardial band
5% of CK
peaks in 6-24 hours
returns to normal in 48 hours
What are the symptoms of an MI?
midline anterior chest discomfort
anxiety, feeling of impending doom
Silent MI's happen more likely in:
What are the four subsets of ACS?
1. non-cardiac chest pain
2. unstable angina
What is non-cardiac chest pain?
could be due to anxiety, GERD, etc
What is unstable angina?
normal cardiac markers
ST segement depression, or T-wave inversion or normal ECG
What is NSTEMI?
elevated cardiac biomarkers
ST segment depression or T-wave inversion or normal ECG
What is STEMI?
Elevated cardiac biomarkers
ST segment elevation at least up a mm
What are the treatment goals for ACS?
minimize infarct size
salvage ischemic myocardium
PCI (angioplasty, stents, atherectomy)
US and NTEMI general treatment strategy
antiischemic and antithrombotic therapy
What's the early invasive treatment strategy in US/NSTEMI?
angiography and PCI within 48-72 hours of symptom onset
When should you do early invasive treatment in US/NSTEMI?
strongest evidence supporting EI is in patients with ST segment depression, increased troponins and/or >3 TIMI score
What's the early conservative treatment strategy in US/NSTEMI?
catheterization/revascularization only if ischemia recurs or is unresolved
What's the dosing scheme for morphine and why is it used?
1-4mg IV Q5-15 minutes PRN
used because morphine's an analgesic, anxiolytic, and reduces preload
When should you use oxygen?
if O2 sat is
What's the dosing scheme used for nitrates?
nitroglycerin 0.4mg SL x 3 doses PRN
if pain persists after 3 doses-->nitroglycerin 5mcg/min infusion-->5-10mcg/min Q5-10 minutes up to 200mcg/min
What's the dosing for aspirin?
162-325mg STAT then 75-162mg daily for life
What's the goal of anticoagulation therapy?
prevent total occulsion of infarct-related artery
What are the 4 options to halt the coagulation cascade?
1. UFH drip
What's the dosing for heparin?
heparin should be dosed at 60-70units/kg bolust then 12-15 units/kg/hour infusion
What's the benefit in using LMWH over UFH?
lower 30 day incidence of death/nonfatal MI
What drugs are considered LMWH?
enoxaparin and dalteparin
What's the dosing scheme for enoxaparin?
1mg/kg SubQ every 12 hours
can consider loading dose of 30mg IV
dose Q24 hours if CrCl
What's the dosing scheme for dalteparin?
120units/kg SubQ Q12 hours
synthetic heparin pentasaccharide
it binds to AT
no aPTT monitoring
What's the dosing for fondaparinux?
2.5mg IV x 1 dose then 2.5mg SubQ daily
When is fondaparinux contraindicated?
direct thrombin inhibitor
What three drugs are thienopyridines?
What drug is considered thienopyridine-like?
How is ticlodipine dosed?
ticlodipine is 250mg BID
how is clopidogrel dosed?
clopidogrel is dosed 300-600mg loading, then 75 mg QD. ideally, want loading dose to be >6 hours before a PCI
How is prasurgrel dosed?
60mg loading and then 10 mg daily
If patient is
Does prasugrel need to be dose adjusted for renal/hepatic impairment?
Should NSAIDS be avoided with prasugrel?
When is prasugrel contraindicated?
if patient has had a prior TIA/CVA
How long should prasugrel be held before CABG?
>7 days prior to CABG
When is ticargrelor contraindicated?
history of intracranial bleeding
severe hepatic dysfunction
When are thienopyridines used?
in place of aspirin if asprin allergic
in addition to aspirin up to 9 months if EC
in addition to aspirin up to 12 months if after PCI
What's the goal of glycoprotein IIB/IIIA inhibitors?
prevent total occulsion of infarct-related artery
Why are glycoprotein IIB/IIIA inhibitors used?
to prevent ishemic complications
Do glycoprotein IIB/IIIA inhibitors replace anticoagulation?
No! glycoprotein IIB/IIIA inhibitors increase mortality if used without LMWH/UFH
EI strategy is when PCI is planned. What's the protocol for glycoprotein IIB/IIIA inhibitors?
use abciximab or acceerated dosed eptifibatide if PCI within 4 hours of presentation
Use tirofiban or eptifibatide if treated medically for first 48 hours
When to NOT use GPIIb/IIIA?
if clopidogrel 300mg loading was given >6 hours prior to cath
Is there a benefit to using abciximab in EC?
no, there's no benefit
How do beta-blockers work?
slow the heart rate to 55-60bpm-->reduce cardiac workload-->decrease myocardial oxygen consumption
How is metoprolol dosed?
5mg IV Q5min x 3 doses, then 25-50mg PO BID
What are the absolute contraindications of beta-blockers?
What are relative contraindications of beta-blockers?
history of asthma
current use of non-dihydropyridine CCB
uncontrolled insulin-dependent diabetes
When are ACEI used?
use in patients with hypertension, diabetes, LVEF
AMI artificially depresses cholesterol profile by 1/3 to 1/2.
When do you use an aldosterone blocker?
patients who are post-MI symptomatic HF with EF
Which aldosterone blocker do you start with?
spironolactone. If patient experiences breast enlargement-->do eplerenone.
BB-stronger data in STEMI (don't do if patient also has HF!)
Primary PCI vs. Thrombolytic
primary PCI preferred in hospitals with cardiac cath lab.
Primary PCI also preferred for: high risk patients, contraindications to fibrinolysis, late presentation, diagnosis of STEMI is in doubt
Thrombotic needs to happen within 30 minutes of getting to hospital
When does cath lab need to happen?
within 90 minutes of hospital arrival
Which drug needs to be given ASAP before PCI?
When does a thrombotic need to happen?
within 30 minutes of hospital arrival
Which thrombolytics are non-selective?
Which thrombolytics are selective?
Difference in outcomes between cath lab and thrombolytics?
stent group had less than half the mortality as the TPA group-->GO TO CATH LAB
Absolute contraindications to thrombolytics?
any prior hemorrhagic CVA
ischemic CVA within 3 months
active internal bleeding
Relative contraindications to thrombolytics?
history of TIA
Should you use glycoprotein IIB/IIA inhibitor?
NO, BAD IDEA
In STEMI patients, is anticoagulation DC'ed immediately after PCI/CABG?
if patient's stented-->add thienopyridine