Venous and Arterial Thrombosis

Question 1

What are some examples of clinical pictures which arise as a result of a) arterial thrombosis? b) venous thrombosis?

Answer 1

a) MI, stroke, PVD b) DVT or PE

Question 2

In a) arterial and b) venous thrombosis, the clot is rich in what?

Answer 2

a) platelets b) fibrin

Question 3

What is the important concept of the pathophysiology of venous thrombosis?

Answer 3

Virchow’s triad - vessel wall, hypercoagulability and stasis

Question 4

Vessel wall damage predisposing to venous thrombosis is usually caused by what?

Answer 4

Problems with the valves

Question 5

What aspects of the haemostatic system are raised to cause hypercoagulability?

Answer 5

TF, VWF and factor VIII

Question 6

What are some causes of venous valve damage?

Answer 6

Increasing age, previous thrombosis

Question 7

What are some of the main risk factors for venous thrombosis?

Answer 7

Age, obesity, increased oestrogen, immobility, thrombophilia, previous VTE

Question 8

How will a DVT present?

Answer 8

Hot, swollen, tender lower limb and potentially pitting oedema

Question 9

What is the main differential of a DVT?

Answer 9

Cellulitis

Question 10

How will a PE present?

Answer 10

Pleuritic chest pain, CV collapse/death

Question 11

If a person survives a PE, what can this lead to?

Answer 11

Hypoxia and right heart strain

Question 12

What is the main treatment for venous thrombosis? What are some options?

Answer 12

Anticoagulants / Warfarin, heparin, NOACs

Question 13

Thrombophilias most commonly arise because of a deficiency of what?

Answer 13

Naturally occurring anti-coagulants

Question 14

Hereditary thrombophilias describe a group of individuals who have an increased tendency to develop what?

Answer 14

Premature, unusual and recurrent thromboses

Question 15

What is an example of an inherited thrombophilia? Describe how it works?

Answer 15

Factor V Leiden - factor V works normally, but it is less efficiently switched off by proteins C/S

Question 16

You should consider screening for a hereditary thrombophilia when?

Answer 16

Family history of VTE or known thrombophilia, unusual or recurrent venous thrombosis, venous thrombosis aged < 45

Question 17

What is the management of thrombophilia with no or one VTE?

Answer 17

Advice on avoiding other risk factors, short term anticoagulation in periods of known risk or to treat a thrombotic event

Question 18

What is the management of thrombophilia with recurrent thrombotic events?

Answer 18

Long term anticogulation

Question 19

Not everyone with a thrombophilia will have a thrombotic event - why is this?

Answer 19

Risks tend to multiply, so if they avoid other risks then they should be okay

Question 20

What is the most important factor in assessing the risk of recurrent thrombotic events?

Answer 20

The history

Question 21

What are some factors which would increase a person’s risk of developing recurrent thrombotic events?

Answer 21

Family history, unprovoked thrombotic event, previous thrombosis

Question 22

In terms of venous thrombosis, when should people be given long-term anticoagulation?

Answer 22

After a second unprovoked thrombus

Question 23

What is the main acquired thrombophilia?

Answer 23

Anti-phospholipid syndrome

Question 24

Which of the following is a stronger risk factor for thrombosis - inherited or acquired thrombophilias?

Answer 24

Acquired

Question 25

What are the main features of anti-phospholipid syndrome?

Answer 25

Recurrent thromboses (arterial and venous), recurrent or late foetal loss, mild thrombocytopenia

Question 26

Why does anti-phospholipid syndrome occur?

Answer 26

A conformational change in beta2 glycoprotein 1 which leads to activation of both primary and secondary haemostasis as well as vessel wall damage

Question 27

What are some investigation results which might show in someone with anti-phospholipid syndrome?

Answer 27

Positive for lupus anticoagulant, prolonged APTT

Question 28

People with anti-phospholipid syndrome often have a raised APTT - do they have an increased risk of bleeding?

Answer 28

No

Question 29

How is anti-phospholipid syndrome treated?

Answer 29

Low dose aspirin and either warfarin or LMWH

Question 30

What is the main reason for thrombus formation in arteries?

Answer 30

Atherosclerosis

Question 31

What is atherosclerosis?

Answer 31

Damage to the endothelium caused by recruitment of foamy macrophages rich in cholesterol to form plaques

Question 32

Stable atherosclerotic plaques can cause what conditions?

Answer 32

Stable angina, intermittent claudication

Question 33

What is the big risk of having a stable atherosclerotic plaque?

Answer 33

It will become unstable and rupture, recruiting platelets and causing acute thrombosis

Question 34

What are some risk factors for arterial thrombosis?

Answer 34

Smoking, hypertension, high cholesterol, diabetes

Question 35

Why do hypertension, smoking and diabetes increase risk of arterial thrombosis?

Answer 35

They damage the vessel wall and activate platelets

Question 36

Why do high cholesterol and diabetes increase risk of arterial thrombosis?

Answer 36

Cholesterol accumulates in the plaques

Question 37

How is arterial thrombosis treated?

Answer 37

Modifying risk factors for atherosclerosis and anti-platelet drugs (mainly aspirin)