Thromboembolic Drugs Flashcards
Reason for selecting heparin (i.e. due to its inability to cross membrane barriers) as anticoagulant rather than warfarin)
Pregnancy
Doing this near eye, brain, or spinal cord is a contraindication for anticoagulants
Surgery
Can be used to measure anticoagulation for drugs such as rivaroxaban; not in notes but a version of this is not now also used to measure unfractionated heparin and low molecular weight heparin
Antixa
Recombinant human form purified from goat’s milk is available for those with deficiency, but it is expensive
Antithrombin
Substrate for plasmin
Fibrin
Vitamin K-dependent anti-clotting factor with shorter half-life than several other factors, its disappearance is reason warfarin administration can cause a pro-coagulant phase
Protein C
Indication for alteplase, especially when within 3-6 hours and option of percutaneous coronary intervention is unavailable
Acute myocardial infarction
Indication for rivaroxaban or dabigatran
Nonvalvular atrial fibrillation
Indication for GP IIb/IIIa inhibitor to limit/prevent ischemia
Acute coronary syndromes
Low-molecular weight heparins are now the drugs of first choice for the treatment and prevention of this
Deep venous thrombosis
Can be induced by unfractionated heparin and low-molecular weight heparin; fondaparinux will not induce but should not be used as a replacement anticoagulant as it can exacerbate the situation
Thrombocytopenia
Contraindication for alteplase and most serious concern with its use
Intracranial hemorrhage
If high risk for this causing acute coronary syndrome, a daily dose of aspirin may be indicated
Coronary heart disease
Leading to decreased levels of VKORC1 (Vitamin K epoxide reductase complex subunit 1) This is found in ~90% of asians and is why they are more sensitive to warfarin than blacks
Genetic variability
A treatment for bleeding (tranexamic acid is another), it prevents activation of plasminogen and directly inhibits plasmin
Amino caproicacid
Platelet derived ligand for autocrine/paracrine stimulation of aggregation via P2Y12 receptors
ADP
Among the best selling drugs in the world, it suppresses platelet aggregation by irreversibly blocking P2Y12 receptors
Clopidogrel
Indication for alteplase if acute and massive, otherwise focus on limiting likelihood of more with anticoaguluants
Pulmonary embolism
Release of this GPCR ligand from endothelial cells keeps platelets in an unactivated state
PGI2
Sequence of letters in a general drug name that suggests blockade of P2Y12 receptors
-GREL
Breaks down a blood clot when bound to it, when circulating it breaks down various clotting factors unless bound by alpha2-antiplasmin
Plasmin
Comparative color of arterial clots due to abundance of platelets of this side of circulation; reason platelet targeting drugs are chosen for problems there
White
Platelet receptors that allow the platelets to link together (aggregate), drugs that block these receptors block the final common pathway of platelet aggregation and are therefore the most effective antiplatelet drugs
GpIIb/IIIa
Dabigatran was found to be inferior to warfarin at inhibiting thromboembolism in these
Mechanical heart valves
Can be used to assess anticoagulation caused by dabigatran
Diluted thrombin time
Characteristic of both onset and offset of warfarin’s anticoagulant effects
Slow
Synthetic pentasaccharide, the minimum sequence needed to bind to antithrombin and inhibit factor Xa; sequence is too short to form the ternary complex with thrombin that is needed to inhibit thrombin activity
Fondaparinux
Needed by clopidogrel for activation and inhibited by proton pump inhibitors; reason Prilosec media mention Plavix and vice versa
CYP2C19
Enzyme thought to be responsible for synthesis of platelet inhibitor PGI2 by endothelial cells; its selective sparing by low doses of aspirin is thought to explain the cardiovascular benefits of aspirin and the adverse effects associated with withdrawn drug rofecoxib
COX2
Procedure (abbr.) that is indication for a GpIIb/IIIa inhibitor, which is used to prevent rapid re-occlusion
PCI
Required for synthesis of biologically active clotting factors II, VII, IX, X, protein C, and protein S among others, and antidote for warfarin
Vitamin K
When severe and uncontrolled, a relative contraindication for alteplase
Hypertension