Flashcards in STEMI Deck (56)
What is the recommended anti-platelet therapy for Class I NSTE-ACS patients?
-Use clopidogrel if ASA intolerant/allergic
-Use a GP IIb/IIIa inhibitor if cath and PCI planned (max tx = 8 days)
What is the recommended anti-platelet therapy for Class IIa NSTE-ACS patients?
-Use GP IIb/IIIa inhibitor in high risk pts if invasive strategy NOT planned
-Use a GP IIb/IIIa inhibitor in pts receiving clopidogrel if cath and PCI planned
What is the recommended anti-platelet therapy for Class IIb NSTE-ACS patients?
Use a GP IIb/IIIa inhibitor in low risk pts when PCI NOT planned
What is the recommended anti-platelet therapy for Class III NSTE-ACS patients?
Use abciximab in pts when PCI is NOT planned
Why is anti-platelet therapy essential in ACS?
Prevents thrombosis from plaque rupture
Chewing aspirin tablets inhibits platelets ___ faster
162 mg daily of aspirin completely inhibits:
325 mg daily of aspirin is max effective dose for ____
Peak serum concentration of aspirin occurs within:
How do NSAIDs and aspirin interact?
-Compete for same receptor
-NSAIDs block and prevent acetylation
-Space these 3 hours apart
Why is aspirin held for 6 hours after CABG and 24 hours after thrombolytics?
Prolonged wound healing
What is clopidogrel and what does it do?
-Selective irreversible inhibition of ADP-mediated platelet activation (cold, shear stress)
Clopidogrel binds ___ but has no effect on ____
-P2Y12 and P2Y1 receptors
-No effects on TXA2, PGI2
Which anti-platelet has extensive hepatic metabolism?
Activity of clopidogrel is reduced by:
PPIs and other potent CYP219 inhibitors
Clopidogrel has reduced bioactivation in which population?
Persons of Chinese ancestry
How is clopidogrel used after coronary stent placement?
With ASA for up to 1 year
What is ticlopidine?
-Irreversible thienopyridine P2Y12 inhibitor
-Clopidogrel/prasugrel now replaces this
How does dipyridamole work?
-Inhibits adenosine deaminase and PDE
-Allows cAMP and adenosine accumulation and vasodilation
How does cilostazol work?
-Inhibits PDE 3
-Inhibits vascular SMC proliferation
How do GP IIb/IIIa inhibitors work?
-Typically the receptors bind fibrin, thrombin, vWF
-Allows for adhesion, activation, aggregation of platelets
-Blocking the receptors prevents clotting
How does eptifibatide work?
-Selective, reversible, competitive GP IIb/IIIa inhibition
-Temporarily blocks fibrin cross-linking
When should you be cautious with eptifibatide?
-PTT 45+ secs
-CrCl less than 50
When should you be cautious with tirofiban?
-Platelets less than 150K
-PTT 45+ secs
-CrCl less than 30
What is abciximab and how does it work?
-Mouse monoclonal antibody
-GP IIb/IIIa inhibitor
-Binds and dissociates rapidly
What is a major ADE to be aware of with abciximab?
Hypersensitivity reactions from infusion
What type of compound is Heparin?
Where is endogenous heparin found?
LMWH favors inhibition of which factor?