Angio-CT and Antiplatelet Drugs Overview

Study Notes

Aspirin: Inhibits TXA2 synthesis (0.075 - 0.5 mg)
Ticlopidine: Inhibits ADP (2 x 0.25 mg)
Clopidogrel: Inhibits ADP (1 x 0.075 mg)
Prasugrel: Inhibits ADP (loading dose 0.3 - 0.6 - 0.9 mg, maintenance 5 or 10 mg)
Abciximab: Blocks GP IIb/IIIa receptor (0.25 mg/kg bolus, then 0.125 µg/kg/min)
Tirofiban, Lamifiban, Fradofiban: Block GP IIb/IIIa receptor (0.01 mg/kg bolus, then 0.15 µg/kg/min)
Eptifibatid: Blocks GP IIb/IIIa receptor (0.18 mg/kg bolus, then 2 µg/kg/min)
Prostacyclin analogues: Inhibit platelet aggregation and vasoconstriction
Ticagrelor: Inhibits ADP

Heparin: Inhibits thrombin and other coagulation factors (APTT monitoring)
Low Molecular Weight Heparins (LMH): Enoxaparin, Dalteparin, Nadroparin
Hirudin and synthetic analogues: Bivalirudin, Lepirudin (APTT monitoring)
Polysaccharide group: Fondaparinux, Idraparinux
Antagonists of Vitamin K: Warfarin (INR monitoring), Acenocumarol
Non-Vitamin K Antagonist Oral Anticoagulants (NOACs):
- Gatranes: Xymelagatran (liver toxicity), Dabigatran
- Xabanes: Riwaroksaban, Apiksaban, Betriksaban, Endoksaban

A series of enzymatic reactions leading to the formation of a fibrin clot:
- Factors XIII, XII: Initiate the cascade
- Factor Xa: Converts prothrombin (factor II) to thrombin (factor IIa)
- Thrombin: Converts fibrinogen (factor I) to fibrin
- Factor XIII: Stabilizes the fibrin clot

Vitamin K Antagonists: Inhibit the synthesis of coagulation factors II, VII, IX, X in the liver
INR: International Normalized Ratio, used to monitor warfarin therapy (therapeutic range 2-3.5)
NOACs: Well tolerated, fewer side effects, do not require INR monitoring

Streptokinase: Non-specific fibrinolytic drug
Anistreplase: Modified streptokinase
Urokinase: Non-specific fibrinolytic drug
Alteplase (tPA): Tissue plasminogen activator, more specific fibrinolytic drug
Tenecteplase (TNK–tPA): Modified tPA