Thrombophilia Flashcards
What is hemostasis?
During vessel wall clot formation, it is the perfect balance between hemorrhage and thrombus formation.
Name the 3 major natural inhibitors of coagulation.
- Antithrombin III
- Protein C
- Protein S
Name the principle inhibitor of tPA and uPA and its source.
Plasminogin Activator Inhibitor-1 (PAI-1)
-comes from alpha granules of platelets
Name the principle inhibitor of plasmin and its source.
Alpha-2-antiplasmin
-bound to factor XIIIa
Best way to check for pulmonary embolism (PE) due to a hypercoagulable state.
Spiral CT
What is the westermark sign?
Seen on spiral CT. It is collapse of vessels from oligemia (low blood flow) distal to a pulmonary embolus lodged near the hilum of a lung.
Pathology of Factor V Leiden.
Factor V cannot be inactivated because of resistance to activation of protein C (APC resistance). Results in hypercoagulable state.
Factor VIII would also remain uninhibited because Protein C also works on that factor.
Where would clots form in Factor V Leiden?
Veins mostly
Which hypercoagulable disease is associated with Neonatal Purpura Fulminans with acquired liver disease?
Protein C Deficiency
Which hypercoagulable disease is associated with DVT in pregnancy?
Antithrombin III deficiency
Which hypercoagulable disease is associated with Neonatla Purpura Fulminans with skin necrosis and warfarin use?
Protein S def.
Where do clots form in Protein S deficiency?
Veins
MOA of antiphospholipid syndrome.
Theory:
Auto Abs bind phospholipids injuring cell membranes and causing clots. Very common in patients with other autoimmune diseases.
Where do clots form in antiphospholipid syndrome?
Arteries
causes Livedo Reticularis, red purpura on skin and urticaria.
Where do clots form in Hyperhomocysteinemia?
Arteries and Veins
Remedy for Heparin induced bleeding.
Protamine Sulfate
Difference in the MOA of LMWHs and UFH.
UFH: binds Antithrombin III, Thrombin, and Factor Xa to create a very stable inactive complex preventing clotting.
LMWHs: bind only ATIII and Factor Xa and don’t create as stable of a complex, making it easier for spontaneous dissolution of the complex and continuation with clotting
Treatment for HIT.
Direct Thrombin Inhibitors
What is necessary after using any thrombolytic agent?
Use of UFH due to a hypercoagulable state and risk of re-clotting.
Drug class used mainly in coronary angioplasty with ASA and heparin.
GPIIb/IIIa inhibitors
-needed for up to a year after a drug-eluting stent is placed
