Deep vein thrombosis (DVT) and venous thromboembolism (VTE)

Question 1

1) What is a VTE?
2) What is a DVT?
3) How can a VTE/DVT cause a PE?

Answer 1

1) Blood clots (thrombi) developing in the circulation
2) Blood clots developing in the venous circulation
3) The clot/thrombus that’s formed in the deep veins can travel through the circulation, through the right side of the heart into the pulmonary arteries and get lodged there - blocking blood flow

Question 2

Name 3 risk factors for the development of DVTs

Answer 2

• Increased age
• Pregnancy
• Synthetic oestrogen (oral contraceptive pill)
• Cancer
• Recent surgery
• Past DVT
• Immobility
• Thrombophilia i.e. antiphospholipid syndrome

Question 3

Name a sign of a DVT

Answer 3

• Calf warmth/tenderness/swelling/oedema
• Mild fever
• Pitting oedema
• Dilated superficial veins

Question 4

Name a method of DVT prophylaxis

Answer 4

• LMWH i.e. enoxaparin
• Anti-embolic compression stockings

Question 5

1) What is the Wells score?
2) What is the blood test done for VTE?
3) This test is sensitive but not specific. Clinically, what does this mean?
4) Name 2 other causes of a raised D-dimer test
5) What other imaging modality is needed for a diagnosis of DVT?

Answer 5

1) Calculation that predicts the risk of a patient presenting with DVT symptoms developing a DVT or PE
2) D-dimer test
3) Helpful in excluding VTE where there is a low probability of a DVT - but a raised result does not mean DVT as there could be other causes
4) Pneumonia, malignancy, heart failure, surgery, pregnancy
5) Doppler ultrasound

Question 6

Management
1) If the cause of DVT is reversible, how long should anticoagulation be done for?
2) Name 2 reasons when anticoagulation should be done for longer than 3 months
3) What anticoagulant is suitable for most patients?
4) What is the first line anticoagulant in pregnancy?
5) What is the first line anticoagulant in antiphospholipid syndrome?
6) When warfarin is used as an anticoagulant for PE or DVT, what is the target INR range?
7) What is an inferior vena cava filter?

Answer 6

1) 3 months
2) Cancer is the cause, unclear cause, irreversible underlying cause, recurrent VTE
3) DOACs i.e. apixaban, rivaroxaban
4) LMWH
5) Warfarin
6) INR 2-3
7) Devices inserted into the IVC, designed to filter the blood and catch any blood clots travelling from the venous system towards the heart and lungs.

Question 7

1) What is Budd-Chiari syndrome?
2) What triad does it present with?
3) What does the pathology of this syndrome cause?

Answer 7

1) Blood clot develops in the hepatic vein, blocking the outflow of blood
2) Abdominal pain, hepatomegaly, ascites
3) Acute hepatitis

Question 8

If someone has a suspected DVT, a raised D dimer but no clot on US, what is done?

Answer 8

Stop anticoagulation and repeat US in 1 week