Thrombosis Flashcards
What are the components of Virchow’s triad?
Endothelial injury
Blood stasis/turbulence
Hypercoagulability
What are the two sites in vessels that are sites for thrombosis?
Turbulent flow
Endothelial injury
True or false: thrombi are usually attached to the underlying vessel
True
Where do arterial thrombi go? Venous?
Grow back to the heart
What are the cytokines that have an antiplatelet effect?
PGI2
NO
What are the anticoagulant properties of the endothelium?
Heparin-like molecules
Thrombomodulin activates protein C
What are the fibrinolytic properties of endothelium?
tPA
What is the protein that allows for platelets to bind?
vWF
What is the role of tissue factor?
Produced by endothelium, activates extrinxic pathway
What is the role of plasminogen activator inhibitors?
What is the drug that inhibits platelet aggregation? How?
ASA
inhibits thromboxane A2
What is the role of the alpha granules that are in platelets?
P selectin
Fibrinogen
Fibronectin
Factor V, VIII
What is in the delta graules of platelets?
ATP AFP Ca Histamine Epi
True or false: the platelet aggregation is reversibles
True
Why is it that the loss of endothelium will result in thrombosis?
Exposures of the ECM and vWF
True or false: turbulences enhances endothelial injury
True
True or false: stasis enhances endothelial injury
False–enhances venous thrombosis
What happens to vWF when there is increased shearing stress d/t faster blood flow?
Unfolds and becomes stickier
What is the role of fibrin in blood clots?
Polymerizes and crosslinks to stabilize clots
What begins the process of clot degradation?
Plasminogen activators convert plasminogen to plasmin
What is the most common cause of hypercoaguability?
Factor V leiden mutation
What happens in antithrombin III deficiency?
Thrombosis
What happens in protein C or S deficiency
Thrombosis
What is disease leads to secondary antiphospholipid syndrome?
SLE
What is the MOA of HITs?
antibodies bind to platelets and activate them
What is antiphospholipid syndrome?
Abs to phospholipids like cardiolipin, inducing coagulation
True or false: superficial thrombosis cause pain, but are not usually concerning
True
What is the vein that is involved in DVTs?
Popliteal, femoral, iliac
What is the vein that is involved in superficial venous thromboses?
Saphenous
True or false: most pts are symptomatic for DVTs
False–50%
DIC is what?
Sudden, widespread fibrin thrombi in the microciculation
When does DIC occur?
infx, prego
What are the effects of DIC?
Infarcts in kidneys, brain, lung etc
What does DIC lead to?
consumption of platelets and clotting factors, increasing the risk of bleeding
What are the four fates of thrombus?
- Propagation
- Embolization
- lysis
- Organization and recanalization (inflammation and fibrosis)
What is the most common preventable cause of hospital death?
PE secondary to DVT
What is the consequences of a medium PE?
Acute respiratory and cardiac symptoms
What is the consequences of a large PE?
Right heart failure and collapse
What is a paradoxical embolus?
Cardiac emboli passing to the right side through the septal defect
Venous infarcts occurs in organs with what type of blood supply?
Single venous outflow
How long does it take for a neuron to die from hypoxia?
3-4 minutes
How long does it take for the heart to die from hypoxia?
20-30 minutes
How long does it take for fibrous tissue to die from hypoxia?
hours
What are the parts of the body with dual blood supply?
Lung
Liver
Hand
What are the most common inciting factors for embolism?
Iatrogenic causes
True or false: EPO increases the risk of thrombosis
True
Is MTHFR a risk factor for embolism
No
Are there many, or is there one type of genotype for: antithrombin deficiency
Many
Are there many, or is there one type of genotype for: factor V leiden
One
What is the prevalence of thrombophilia with factor V leiden?
40-50%
What is the relative risk for heterozygous factor V leiden?
7x
What is the relative risk for homozygous factor V leiden?
80x
What is the relative risk of thrombosis with exogenous estrogen? How about those with factor V leiden, and exogenous estrogen?
- 7
34. 7
True or false: you should always evaluate young pts who have thrombosis for genetic history
True
True or false: you should always evaluate pts who have recurrent miscarriages for genetic history of thrombosis
True
Neonatal purpura fulminans is caused by what?
Homozygous PC or PS deficiency
Is AT (III) deficiency AD or AR?
AD
When does AT(III) deficiency usually present?
Adolescence or earlier
Is PC deficiency AD or AR?
AD
What happens to homozygous PC or PS deficiency?
Death early
Warfarin necrosis is caused by what genetic disease?
PC or PS deficiency
Is PS deficiency AD or AR?
AD
What is the MOA of factor V leiden?
Slow inactivation of factor V by protein C
True or false: factor Va procoagulant activity is not affected by factor V leiden
True
What is the MOA of prothrombin G20210A mutation?
mutation in prothrombin, leading to hypercoagulability
One prothrombotic condition increases the risk of thrombosis how much?
5-8 x