Atherosclerosis, Thrombosis, Embolism

Question 1

Define ‘thrombosis’

Answer 1

Formation of a mass (thrombus) from the constituents of blood within the vasculature during life

Question 2

How does a thrombus differ from a clot?

Answer 2

Thrombus must form during life in the body; clots can form when blood is extracted post-mortem

Question 3

What are the 3 components of Virchow’s triad?

Answer 3

Changes in blood flow
Changes in blood coagulability
Endothelial damage

Question 4

Give some examples of hypercoaguable aquired states

Answer 4

Myocardial infarction
Immobility
Cancer
Prosthesis
AF
Cardiomyopathy
Oral contraceptive use

Question 5

Arterial thrombi are red. True/False?

Answer 5

False

Question 6

Where do arterial thrombi often lodge?

Answer 6

Coronary, cerebral, femoral circulations

Question 7

Define ‘embolism’

Answer 7

Detached intravascular solid/liquid/gas mass carried distal to point of origin

Question 8

Venous emboli commonly infarct peripheral circulation. True/False?

Answer 8

False
Very rare (carried to pul circulation, more likely lodge there)

Question 9

Give examples of factors causing endothelial injury

Answer 9

Smoking
Hyperlipidaemia
Hypertension
Toxins
Infection

Question 10

What do oxygen free radicals do to LDL?

Answer 10

Ingest and trap it within macrophages, forming foam cells/fatty streaks

Question 11

In a pre-test probability (PTP) score for DVT, the scoring does not apply in what situations?

Answer 11

If you have had a previous DVT
If you are pregnant

Question 12

A PTP score for DVT of 3 or more is high risk. True/False?

Answer 12

True

Question 13

D-dimer can both rule out and diagnose DVT. True/False?

Answer 13

False

Question 14

What is D-dimer?

Answer 14

A breakdown product of fibrin

Question 15

If D-dimer levels are low, a DVT is unlikely. True/False?

Answer 15

True

Question 16

If D-dimer levels are high, a DVT is very likely. True/False?

Answer 16

False
D-dimer levels are raised by many things (infection, MI, surgery)

Question 17

If your PTP score is low and D-dimers are low, a DVT can be excluded. True/False?

Answer 17

True

Question 18

If your PTP score is low and D-dimers elevated, what is the next investigation for diagnosing a DVT?

Answer 18

(Doppler) ultrasound

Question 19

If your PTP score is high and D-dimers low and US negative, DVT can be excluded. True/False?

Answer 19

True

Question 20

If your PTP score is high and D-dimers high but US negative, DVT can be excluded. True/False?

Answer 20

False
Repeat US before completely excluding DVT

Question 21

What is the mainstay of DVT treatment?

Answer 21

Anticoagulation (LMWH heparin, warfarin)
TED compression stockings

Question 22

What is phlegmasia dolens?

Answer 22

DVT causes obstruction of arterial flow due to back pressure created

Question 23

How is phlegmasia dolens usually treated?

Answer 23

IVC filter through femoral artery which prevents thrombus entering lungs

Question 24

What is the first line imaging modality of choice for PE?

Answer 24

V/Q scan

Question 25

What is the advantage of a caval filter for acute PE?

Answer 25

Prevents recurrence of PE in short term

Question 26

What is the drawback of a caval filter?

Answer 26

Increases risk of DVT - patients will require anticoagulation if long-term filter

Question 27

When is warfarin contraindicated?

Answer 27

Pregnancy
Increased haemorrhage risk (uncontrolled drug abuse, dementia etc.)