Venous Thromboembolic disease

Question 1

What is a DVT?

Answer 1

A clot that forms around the valves of the deep veins which blocks venous return to the heart

Question 2

What is an arterial clot?

Answer 2

high flow of blood leads to the clot being rich in platelets

Question 3

What is a venous clot?

Answer 3

Pooling of static blood occurs which then forms a fibrin rich clot

Question 4

What are the two types of DVT?

Answer 4

Distal and proximal DVT

Question 5

What are most diagnosed DVTs?

Answer 5

proximal as we dont scan below the knee.

Question 6

What is the mortality rate for a PE alone?

Answer 6

17.5% at 3 months

Question 7

What is the mortality rate for a DVT alone?

Answer 7

0.5-5% at 3 months

Question 8

What are the three components of Virchows triad?

Answer 8

• hypercoagubilty of blood
• turbulent blood flow
• endothelial injury

Question 9

What are some exposing risk factors for VTE?

Answer 9

surgery, trauma, acute medical conditions, central venous catheterisation

Question 10

What are some predisposing risk factors for VTE?

Answer 10

• history of VTE
• chronic heart failure
• Age
• obesity
• immobility
• pregnancy
• hormone therapy
• genetic

Question 11

What can provoked VTE be characterised into?

Answer 11

reversible or irreversable

Question 12

What is an example of a reversible provoked VTE factor?

Answer 12

surgery

Question 13

What is an example of an irreversible provoked VTE?

Answer 13

cancer

Question 14

What is an example of an unprovoked VTE?

Answer 14

no identifiable cause, idiopathic

Question 15

What is the likelihood of a reversible provoked VTE of recurring?

Answer 15

low

Question 16

What are some known consequences of VTE?

Answer 16

• fatal PE
• risk of recurrent VTE
• Post thrombotic syndrome
• Chronic thromboembolic pulmonary hypertension
• reduced quality of life

Question 17

What is post thrombotic syndrome?

Answer 17

A collection of symptoms occurring in nearly 1/3 of patients within 5 years after idiopathic DVT

Question 18

What are the characteristics of PTS?

Answer 18

• pain
• oedema
• hyperpigmentation
• eczema
• varicose collateral veins
• venous ulceration

Question 19

What is Chronic thromboembolic pulmonary hypertension?

Answer 19

CTPH is a relatively rare, but serious, complication of PE.2
In CTPH, the original embolic material is replaced over time with fibrous tissue that is incorporated into the intima and media of the pulmonary arteries. This material may occlude the pulmonary artery, leading to pulmonary artery resistance and, ultimately, right heartfailure.2

Question 20

What is the presentation of CTEPH like?

Answer 20

initially asymptomatic and followed by progressive dyspnoea and hypoxaemia

Question 21

What is the cure?

Answer 21

Operation to remove the clot which will cure the hypertension
-meds are also available

Question 22

How do you investigate VTE?

Answer 22

• probability testing (asses the likelihood by assessing risk factors as well as symptoms)
• D dimer
• ultrasound

Question 23

What do the D dimer results indicate?

Answer 23

• negative D dimer test as well as low probability in testing will mean no PE
• positive D dimer does not indicate that a PE is present

Question 24

How is the ultrasound carried out?

Answer 24

• Look at the groin and popliteal veins.

- If they can compress the vein then the pressure isn’t high and so there is no clotting above this point.

Question 25

What are the two types of probability tests used in assessing VTEs?

Answer 25

- Wells score | - revised Geneva score

Question 26

How are the probability tests used?

Answer 26

- If the probability comes out low then check d dimer and if that's negative then dont need ultrasound - If the probability is high then need ultrasound regardless of D dimer

Question 27

What other two imaging techniques can be used?

Answer 27

- CXR (doesn't usually show a PE) | - V/Q scan (good in peripheral PEs) (can have inconclusive results)

Question 28

What drugs are used to treat DVT and PE?

Answer 28

- Anticoagulants - Thrombolysis - Analgesia

Question 29

What are the mechanical interventions for DVT and PE?

Answer 29

- graduated compression stockings | - IVC filters

Question 30

What are the screenings done for DVT and PE?

Answer 30

-screen for cancer and thrombophilia

Question 31

How long should you treat provoked VTE?

Answer 31

3 months

Question 32

How long should you treat unprovoked VTE?

Answer 32

At least 3 months but you need to assess consequences of long term use of drugs

Question 33

What are the main anticoagulants you should use?

Answer 33

-rivaroxaban -apaxiban (dabigatran and Edoxaban are not often used)

Question 34

What are the major haemorrhage rates like in the use of apaxaban?

Answer 34

It has the same rate of major bleeding as placebo so is a safer drug than warfarin

Question 35

What are special cases to be considered when using drug treatment?

Answer 35

-All men who have had an episode of a PE that are unprovoked or irreversible factors should continue with anticoagulants -Drug users (may have damaged vessels so high haemorrhage risk) -cancer patients (use fragmin instead) -

Question 36

When should you give thrombolysis?

Answer 36

iliofemoral DVT

Question 37

When should you use thrombolysis in relation to PEs?

Answer 37

- In PE patients with haemodynamic instability | - In PE patients who aren't improving with treatment

Question 38

What are compression stockings used for?

Answer 38

- to prevent post thrombotic syndrome - need to be worn as soon as possible after diagnosis - worn for at least 2 years post thrombosis - only on affected leg

Question 39

What are IVC filters?

Answer 39

- A mechanical plate that sits in the inferior vena cava and catches clots from thrombi. They prevent death by PE - Used alongside anticoagulant therapy

Question 40

What are the issues with IVC filter?

Answer 40

They can stick into the aorta and cause fistulas They can also cause thrombis Try to avoid use