Drugs to Treat PAD and DVT Flashcards
Why can fondaparinux and low molecular weight heparins be administered at home?
Because of their predictable pharmacokinetics
What is an example of drugs that can contain vasoconstrictors that can exacerbate PAD?
Cold remedies
What is the function of CYP2C9?
Metabolizes the more potent S warfarin; numerous polymorphisms in this gene and those decreasing its activity against warfarin are more common in Caucasians, increasing Warfarin potency 3-5x
Contraceptive use is associated with increased risk of what?
DVT in younger women due to increased clotting factor synthesis
Name risk factors for PAD
obesity, smoking, diabetes, increased cholesterol levels
What are white clots?
Abundance of platelets in arteries; reason platelet targeting drugs are chosen for problems there
What is the first line tx for decreasing risk of PAD?
Statins
What is a common cause of PAD?
atherosclerosis
Kidney disease can hasten the elimination of what?
clotting factors
What are red clots?
Blood clots in the venous circulation; consequence of large fibrin mesh that forms
What is a potential sx of DVT?
pain
What is a surgical tx option for PAD?
angioplasty
What is a sign of PAD?
bruits
Petechiae are a common sign of what?
platelet defects, uncommon with clotting factor defects
What is often recommended to reduce risk of DVT?
exercise; cardiomyositis is an instance where it is not recommended
What assay can be used to measure anticoagulation for drugs such as rivaroxaban?
Anti-Xa
What was the first use for warfarin?
rat poison
what is a stent?
Wire mesh placed in stenotic blood vessels to keep the lumen open; often drug-eluting
What is cilostazol?
Type 3 phosphodiesterase inhibitor that prolongs the life of cAMP in platelets; used to surpress platelet aggregation and cause peripheral vasodilation; indicated for intermittent claudication associated with PAD
How do deficiencies of clotting factors manifest?
as deep tissue bleeding forming large subcutaneous and soft tissue hematomas or hemarthroses; may be delayed/oozing after procedures
what is a frequent consequence of PAD?
erectile dysfunction
Which drug can cause necrosis?
Warfarin; occurs when there is a rapid fall in protein C leading to a hyper coagulable state; reason why pts must be transitioned to warfarin therapy rather than abruptly started on it
How are the legs characterized in PAD?
have shiny skin
What can also contribute to DVT risk?
genetic variability; also seen in VKORC1 (reason why AA can be resistant to warfarin and Asians more sensitive to it)
Liver disease can impair the synthesis of what?
clotting factors
What leads to platelet activation/thrombosis and platelet removal by splenic macrophages?
Platelet Fc receptors bind an IgG bound to heparin and PF4 in heparin induced thrombocytopenia
What is released by thrombin?
fibrin; polymerized form is a substrate for plasmin
What is a black box contraindication for cilostazol?
hepatic failure
Pedal pulses tend to be weak or absent with what?
PAD
What is generated as a consequence of factor X activation?
thrombin; inhibited by unfractionated heparin but not LMW heparin or fonaparinux
What is an element of treatment strategy when switching from a DOAC to warfarin, but not when switching from one DOAC to another?
overlap
Carbamazepine, phenytoin, and phenobarbital all decrease the effects of what?
Warfarin because they induce the synthesis of its metabolic enzymes
What is a challenge associated with both heparin and warfarin?
dosing; which is a reason for frequent coagulation tests are required
What is the generic name reference to the drug class that inhibits factor Xa?
Xaban
