DVT and Pulmonary Embolism

Question 1

What is VTE ?

Answer 1

Venous Thromboembolic Disease
-Covers both DVT and PE.

Question 2

What is a DVT ?

Answer 2

Deep Venous Thrombosis
-Thrombus formed in deep venous circulation (usually legs) but can be anywhere
-Distal vein thrombosis refers to DVT of the calves
-Proximal vein thrombosis refers to DVT of the popliteal vein or the femoral vein.

Thrombus = clot

Question 3

What is Virchow’s triad ?

Answer 3

The three key factors that contribute to thrombosis

Question 4

What are risk factors for VTE ?

Answer 4

Question 5

How does DVT present ?

Answer 5

Painful and swollen limb with redness and heat.
Tenderness along vein.
Sub acute development.
No other obvious cause. (classical description)

Hard to determine from visual appearnce; may be deceptive

Question 6

How does PE present ?

Answer 6

Sudden SOB with Pleuritic Pain +/- Collapse +/- Haemoptysis. Hypoxia and tachycardia on Obs. BP may be low

Pleuritic pain is sharp stitich like pain in sides when breathing in

Question 7

What are D-dimers ?

Answer 7

Breakdown product of cross linked fibrin
-Produced as clots form
-High negative predictive value (>98%) for VTE
-Low positive predictive value for VTE
(Negative result means very unlikely clotting, positive result doesnt mean much as many things can elevate them)

Question 8

Which actions are taken for patients of different risks of VTE ?

Answer 8

Mod-high probability PE or DVT likely, patient needs a scan (D-dimers skipped)

DVT unlikely/low risk PE, D-dimers checked
-High D-dimers means scan, normal means VTE excluded

Question 9

How are compression tests used in assessing for DVT ?

Answer 9

Compressible distal vein means no clot in proximal vein
-Proximal clot would cause pressure backup so distal vein would be incompressible
-Negative compression test but high risk and pos d-dimer will need to be brought back in

Question 10

What is V/Q scanning ?

Answer 10

Ventillation/perfussion scanning
-Looking at inconsistencies in darkness between images
-Not that good for PE

Question 11

How are different risk severities of PE treated ?

Answer 11

High Risk = Thrombolysis then oral anticoagulation
Intermediate or Low Risk = Oral Anticoagulation

(Hghly specialist centres may consider some Intermediate Risk patients for Thrombolysis)

Haemodynamics = blood flow

Question 12

How is DVT treated ?

Answer 12

Oral Anticoagulation
-Few need thrombolysis, only done in highly specialist centres

DVT not usually that bad

Question 13

How does oral anticoagulation break down a clot ?

Answer 13

Indirectly by putting body into state where more clot breakdown than formation is ocurring

Question 14

What is thrombolysis ?

Answer 14

Aggressive clot destruction.
-Works better in veinous clots as they are more fibrin rich than arterial clots, which are more platelet rich
-Risk of bleeding tho

Aka fibrinolysis

Question 15

What is the gold standard investiagtion for DVT ?

Answer 15

Full leg veinous doppler echo scan is
-Above and below knee
-Time consuming
-Checks for blood flow and its direction

Question 16

Give examples of anticoagulants which can be used for VTE

Answer 16

1) Direct oral anticoagulants
-e.g. Apixaban or Rivaroxaban or edoxaban (10a inhibtors)
-first line for VTE
-As good as warfarin but safer

2) Vitamin K antagonists
-e.g. Warfarin, largely repalced by DOACs
-careful monitoring of levels in blood

3) Low molecular weight warfarin
-still used in active cancer and PE

Question 17

What is post thrombotic syndrome ?

Answer 17

Occurs in nearly one-third of patients within 5years after idiopathic DVT

Characterised by:
-Pain (variable severity, not many treatment options)
-Oedema
-Hyperpigmentation
-Eczema
-Varicose collateral veins
-Venous ulceration

Question 18

What is Chronic Thromboembolic Pulmonary Hypertension (CTEPH) ?

Answer 18

Serious complication of PE
Up to 5% of patients with PE are reported to develop CTPH
Initial phase of disease often asymptomatic and followed by progressive dyspnoea and hypoxaemia
Right heart failure can frequently occur
Progressive condition associated with mortality rates of 4–20%

Question 19

What is HERDOO-2 scoring

Answer 19

Scorring critera for women to discontinue anticoagulation after unprovoked VTE
-Men recieve lifelong unless bleeding issues

(Female patients may wish to continue anticoagualation due to angst despite low score)

Unprovoked = cause unknown