Thrombosis

Question 1

What is the difference in location between arterial and venous thrombus?

Answer 1

Arterial - coronary, cerebral, peripheral

Venous - DVT, PE

Question 2

Arterial thrombus:
-what type of thrombus is it?

Venous thrombus
-what type of thrombus

Answer 2

Arterial thrombus = white, platelet rich thrombus (atherosclerosis)

Venous thrombus = red, RBC rich thrombus, virchows triad (hypercoagulability, endothelial injury/dysfunction, stasis)

Question 3

What is the difference in treatment between arterial and venous thrombus?

Answer 3

Arterial: aspirin and other antiplatelets, manage risk factors

Venous: anticoagulants - heparin, warfarin, NOAC

Question 4

List 7 risk factors for VTE due to stasis

Answer 4

Age 
Pregnancy - baby presses on veins
Previous DVT/PE
Malignancy
Paralysis
Trauma/surgery
marked obesity

Question 5

List 2 risk factors for VTW due to vessel wall dysfunction/damage

Answer 5

Age - valves degenerate with age

Previous DVT/PE - damaged valves

Question 6

List 8 risk factors for DVT/PE due to hypercoagulable state (hypercoagulable state is assoc. with release of TF, raised vWF and raised factor VIII)

Answer 6

Age
Pregnancy
Oestrogen therapy (COCP/HRT)
Malignancy
Infection
Thrombophilia
Trauma/surgery
Puerperium

Question 7

There are 3 potential mechanisms for thrombophilia (hypercoagulation) - what are these?

Answer 7

Increased coagulation activity (primary or secondary haemostasis)

Decreased fibrinolytic activity

Decreased anticoagulant activity (antithrombin III, protein C and S)

Question 8

what are the 4 different types of hereditary thrombophilias?

Answer 8

1: protein C deficiency
2: Protein S deficiency
3: prothrombin 20210 (slightly changed prothrombin)
4: Factor V leiden - factor V is resistant to activated protein C (most common inherited risk factor for thrombosis)

Question 9

What is the cause for an acquired thrombophilia?

Answer 9

Antiphospholipid syndrome

Question 10

what are 3 clinical features of antiphospholipid syndrome?

Answer 10

1 : recurrent thromboses (arterial and venous)

2: recurrent fetal loss
3: mild thrombocytopenia

Question 11

What is the pathogenesis of antiphospholipid syndrome? what coagulation test is prolonged?

Answer 11

Autoantibody causes a conformational change in B2 glycoprotein 1 which leads to activation of primary and secondary haemostasis and vessel wall abnormalities
-APTT prolonged
(autoantibody is AKA lupus anticoagulant)

Question 12

What is the treatment for antiphospholipid syndrome?

Answer 12

aspirin and warfarin

Question 13

When would you screen for thrombophilia (this is mostly done to rule out antiphospholipid syndrome)

Answer 13

• VTE <45yrs
• recurrent VTE
• unusual VTE
• FH VTE
• FH thrombophilia

Question 14

Risk factors for VTE:

• why do multiple risk factors increase the likelihood a lot more of VTE than just a single risk factor
• as age increases do the amount of risk factors needed increase or decrease?

Answer 14

• risk factors multiply risk (don’t add)

- the older the pt gets the less the risk factors are needed

Question 15

When is long term anticoagulation considered? what has to be taken into account?

Answer 15

balance risk recurrent thromboses with risk serious haemorrhage

Risk recurrent thromboses:

• Hx previous thrombosis (BIGGEST FACTOR)
• spontaneous thrombosis instead of acquired/transient risk factor
• FH
• thrombophilia screen results