Venous thromboembolic disease

Question 1

What is DVT and PE?

Answer 1

• DVT: thrombi form predominantly in venous valve pockets and other sites of presumed stasis
• PE: thomboemboli detach and travel through the right side of the heart to block blood vessels in the lungs

Question 2

What is the difference between distal and proximal vein thrombosis?

Answer 2

Distal vein thrombosis refers to DVT of the calves

Proximal vein thrombosis refers to DVT of the popliteal vein or the femoral vein. These thromboses are termed ‘proximal’ because they are closer to the heart

Question 3

What is virchows triad?

Answer 3

Hypercoagulable state
Endothelial injury
Circulatory stasis

Question 4

what are the risk factors for hypercoaguable state? 6

Answer 4

Malignancy
Pregnancy and peripartum period
Oestrogen therapy
Inflammatory bowel disease
Sepsis
Thrombophilia

Question 5

What are the risk factors for circulatory stasis?4

Answer 5

Left ventricular dysfunction

Immobility or paralysis

Venous insufficiency or varicose veins

Venous obstruction from tumour, obesity or
pregnancy

Question 6

what are the risk factors for endothelial injury?

Answer 6

Venous disorders
Venous valvular damage
Trauma or surgery
Indwelling catheters

Question 7

what is the difference between a provoked and unprovoked DVT? How does this affect management?

Answer 7

Provoked:
attributed to either transient/reversable factors or continuing/irreversable factors

Unprovoked: idiopathic

For provoked DVT there must be at least 3 months VKA therapy
For unprovoked therapy must be longer

Question 8

What are the sudden/long term complications of DVT?

Answer 8

Sudden: PE

Long term:
Post-thrombotic syndrome (PTS)
Chronic thromboembolic pulmonary hypertension (CTEPH)

Question 9

what is post-thrombotic syndrome? what are the clinical features 6?

Answer 9

DVT-induced damage to the valved in deep veins and valvular reflux leading to venous hypertension:

• Pain
• Oedema
• Hyperpigmentation
• Eczema
• Varicose collateral veins
• Venous ulceration

Question 10

What is CTEPH? what are the clinical features 2? is it a progressive condition?

Answer 10

original embolic material is replaced with fibrous tissue incorporated into pulmonary arteries walls.
=may occlude the pulmonary artery, leading to pulmonary artery resistance

Initial phase of disease often asymptomatic and followed by progressive dyspnoea and hypoxaemia

Right heart failure can frequently occur

Progressive condition

Question 11

What is used to investigate suspected DVT?

Answer 11

• probability scores: wells score
• D-dimer level: this is a test of exclusion if level is less than 250
• ultrasound scan

Question 12

What are the 9 elements of the well’s score? what does this class patients under?

Answer 12

Active cancer (treatment within last 6 months or palliative) = 1

Paralysis, paresis, or recent plaster immobilisation of leg = 1

Major surgery or recently bedridden for >3 days in last 4 weeks = 1

Local tenderness along distribution of deep venous system = 1

Entire leg swollen = 1

Calf swelling >3cm compared to asymptomatic leg (measured 10cm below the tibial tuberosity) = 1

Pitting oedema = 1

Collateral superficial veins (non-varicose) = 1

Alternative diagnosis as likely or more likely than that of DVT = -2

The risk of DVT is likely if the score is two points or more, and unlikely if the score is one point or less.

Question 13

What is the management of patients likely to have DVT?

Answer 13

Refer for a proximal leg vein ultrasound scan to be carried out within 4 hours.

If a proximal leg vein ultrasound scan cannot be carried out within 4 hours of being requested:
-Take a blood sample for D-dimer testing.

• Give an interim 24-hour dose of a parenteral anticoagulant (note that the weight of the person will be required to calculate the dose of parenteral anticoagulant)
• Arrange for a proximal leg vein ultrasound scan (to be carried out within 24 hours of being requested).

Question 14

If a patient is unlikely to have a DVT what is the management?

Answer 14

Offer D-dimer test:

If the D-dimer test is positive, same management as for ‘likely DVT” category.

If the D-dimer test is negative, consider an alternative diagnosis to explain symptoms.

Question 15

What is the modified wells score for PE?

Answer 15

Clinical signs of DVT = 3 points
PE most liekly diagnosis = 3 points
HR >100 = 1.5 points
Immobilisation at least 3 days or surgery within 4 weeks = 1.5
Previous diagnosis of DVT/PE = 1.5
Haemoptysis = 1
Malignancy within 6 months = 1

Score of = 4 makes PE unlikely
Score of >4 makes PE likely

Question 16

What is the management for patients with a likely PE?

Answer 16

arrange hospital admission for an immediate computed tomography pulmonary angiogram (CTPA).

Or, if there will be a delay in the person receiving a CTPA, give immediate interim low molecular weight heparin or fondaparinux and arrange hospital admission.

Question 17

What is the management for patient who are unlikely to have a PE?

Answer 17

arrange a D-dimer test:

If the test is positive, treat as ‘likely PE’ patient
If the test is negative consider an alternative diagnosis.

Question 18

What other imaging is used for PE other than CTPA? 2

Answer 18

Chest X Ray – Usually normal in PE. Can show pleural effusions and occasionally infarct

V/Q scan – Ventilation/Perfusion imaging. Demonstrates mismatched perfusion defects. Still a useful test particularly in small peripheral PEs and pregnancy (perfusion only)
Limited by frequency of inconclusive results, hence CTPA has become gold standard

Question 19

What are the four general ways to treat PE and DVT?

Answer 19

Pharmacological interventions

• Anticoagulation
• Thrombolysis
• Analgesia

Mechanical interventions

• Graduated compression stockings
• IVC filters

Screening

• Cancer
• Thrombophilia

Patient information

Question 20

What is the long term anticoagulant management for patients with a first VTE episode?

Answer 20

LMWH for at least 5 days and until INR >/= 2

Warfarin is then started within 24hrs and continued for 3 months

After 3 months long-term is based on benefit risk

Question 21

What is the long term anticoagulant management for patients with VTE with active cancer?

Answer 21

LMWH for 3-6 months

-reassess for continued treatment

Question 22

What is the long term anticoag. management issues for IDU’s?

Answer 22

• Complicated by lifestyle issues
• Risk of haemorrhage/death vs. embolic disease
• Rivaroxaban or Fragmin
• Active vs. Retired injector

Question 23

When is thrombolysis offered in DVT?

Answer 23

Consider patients with symptomaticileofemoral DVT symptoms less than 14 days duration and:

• good functional status and:
• a life expectancy of 1 year or more and
• a low risk of bleeding

Question 24

When is thrombolysis offered in PE?

Answer 24

only if haemodynamically unstable

Question 25

in treatment of VTE:
What are compression stockings preventing?
What type of stockings are used?
When to start wearing them? and how long should patients wear them for?

Answer 25

Used to prevent post thrombotic syndrome (PTS)

Class 2 European standard compression stockings, below knee

To be worn as soon as possible after diagnosis (one week after diagnosis or when swelling is reduced sufficiently and there are no contraindications) on affected leg

To be worn for at least 2 years post thrombosis

(Prescribers should refer to specific product information and contraindications before offering graduated compression stockings)

Question 26

When are IVC filter considered in the treatment of VTE?

Answer 26

• if they can’t have anticoag. treatment

- if they have recurrent proximal DVT/PE and increasing INR/use of LMWH has been considered