Condition – Leg Ulcers

Deep vein thrombosis (DVT)

Please be advised that this website contains graphic medical imagery


A DVT is an abnormal  clot or thrombus with in a vein. Any vein can get a clot within it, but they are most common in the leg veins.

Effects of a DVT

There effects of a DVT  can range from asymptomatic to developing leg ulcers to  a  medical emergency as occurs in a pulmonary embolus or clot  stopping the blood supply to the lung


There are three main  reasons why a DVT develops:.

1.A clotting disorder or thrombophilia

The blood is an amazing fluid, it has to stay liquid inside the blood vessels but if there is any break in the blood vessel wall it is able to clot and prevent more blood from seeping out. There are many 1000s of blood chemicals that ensure this happens successfully. However sometimes one or more of these can be defective resulting in  a  clot  or thrombus with in the blood vessel.  This can be due to a generic / inherited congenital reason or can be an acquired change often as a consequence of an autoimmune reaction. Antiphospholipid syndrome is the most common of the acquired clotting disorders.

2.An underlying cancer or malignancy

In patients with a cancer the blood is more likely to clot with in the veins. Sometimes a DVT  is the first sign  of the cancer. Once a diagnosis of a DVT has been made this will need to be excluded.

3.Immobility and blocked veins

If the blood in a vein stops flowing it is likely to clot causing a DVT. This can occur when  the leg does not move for a period of time as happens

1.on a long haul flight,

2.After an accident, especially to the legs, even a minor one, a DVT can occur while skiing or playing football.  A DVT is more likely if a plaster of Paris cast is used to treat any injury.

3.Any surgery longer than an hour

For this reason if the patient has already had a DVT or the vein has been damaged they are at risk of having another DVT.


Daryll Baker is a Consultant Vascular Surgeon at the Royal Free Hospital London and Clinical Lead for North Central Region Vascular Services.

He read Medicine at Oxford University and trained in Vascular Surgery in Nottingham, London and Edinburgh. He obtained his research PhD from the University of Wales.


Wellington Hospital
34 Circus Road

020 7722 7370

Copyright 2016 The Vascular Consultancy