Antithrombotics

Question 1

• MOA: irreversibly inhibits cyclooxygenase (Cox-1 and Cox-2) via acetylation and thus decreases thromboxance A2 production which inhibits platelet aggregation
• cox-1 affects platelets (low dose)
• cox-2 affects analgesics (high dose)
• available in tablet- regular, chewable, enteric-coated, buffered
• stop 5-7 days in advance prior to procedure

Answer 1

Aspirin

Question 2

what are the indications and adverse effects of aspirin?

Answer 2

indications

• analgesic/antipyretic
• atrial fibrillation
• primary and secondary prevention of CAD
• stroke/ TIA
• peripheral artery disease

Adverse effects

• bleeding, dose-related gastric erosions and intracranial hemorrhage

Question 3

contraindications of aspirin? how is it monitored

Answer 3

Contraindications

• Children < 16 with viral illness (reye’s syndrome)
• patients with asthma
• rhinitis
• nasal polyps

Monitoring

• CBC
• Fecal occult blood test

Question 4

• MOA: inhibition of cyclic nucleotide phosphodiesterase and blockade of uptake of adenosine which both results in increased cAMP (platelet inhibitor)
• indications: stroke prevention: thromboembolic stroke prevention
• adverse effects, HA (up to 40%) GI upset, bleeding

Answer 4

Aspirin/dipyridamole

Question 5

which medications are P2Y12 inhibitors?

Answer 5

Thienopyridine

• clopidogrel
• prasugrel

Cylopentyltriazolopyrimidine

• ticagrelor

Non-thienopyridine

• Cangrelor

Question 6

• MOA: selectively and irreversibly blocks the P2Y12 component of ADP receptors which prevents activation of the GPIIB/IIIa receptor complex (reduced platelet aggregation)
• indications: MI (STEMI and NSTEMI), CVA, percutaneous coronary intervention (PCI), PAD
• Adverse effects: rash, bleeding, rare TTP

Answer 6

Clopidogrel

Question 7

• MOA: irreversibly blocks the P2Y12 component of the ADP receptor to inhibit platelet aggregation
• indication: ACS-PCI thrombosis prophylaxis
• adverse effects: Bleeding, HTN, hyperlipidemia, HA, backache, rare TTP, rash

NEEDS TO BE USED IN COMBONATION WITH ASPRIN

Answer 7

prasugrel

Question 8

what is the boxed warning for prasugrel?

Answer 8

• significant fatal bleeding
• contraindications: hx of stroke/TIA
• do not use in pts who have a urgent CABG surgery
• not recommended in pts > 75 except in patients with DM or prior MI, if possible don’t stope med

Question 9

• MOA: reversibly and concompetitively binds to the P2Y12 component of the ADP receptor to inhibit platelet aggregation
• indications: ACS, PCI, primary prevention in patients with CAD and at high risk for CV events, minor ischemic stroke or high risk TIA
• Adverse effects: bleeding, HA, increase SCr, dyspnea, bradyarrhythmias
• avoid in use in severe hepatic impairment

NEEDS to be used in combonation in aspirin (no dose > 100mg )

Answer 9

Ticagrelor

Question 10

• MOA: selectively and reversibly blocks PY212 component of the ADP receptor to inhibit platelet aggregation
• Use: PCI pts not previously loaded with an oral P2Y12 receptor blocker
• onset 2 minutes (given via IV)
• no antiplatelet effect observed 1 hour after discontinuation
• adverse effects: bleeding, renal insufficiency, dyspnea, hypersensitivity
• Transitioning to oral therapy (clopidogrel/plasugrel vs. ticagrelor)

Answer 10

Cangrelor

Question 11

• MOA: binds to glycoprotein IIB/IIIa receptor which inhibits platelet aggregation
• adverse effets: thrombocytopenia, bleeding, hypotension
• used in the cath labs often for a PCI

Answer 11

Glycoprotein IIB/IIIa inhibitors