What is deep vein thrombosis?
With thrombosis, a blood clot (thrombus) blocks a blood vessel, causing only a little blood to flow through the vessel. Therefore, you must consult your doctor in case of any suspicion of deep vein thrombosis. Blood clots form primarily in the veins of the legs and pelvis. These blood vessels collect the blood from the feet, the legs, and the pelvis and transport it back to the heart. A deep vein thrombosis must be treated by a doctor immediately.
The risk of a pulmonary embolism occurring is particularly high if the deep veins of the leg are affected. A thrombus in the affected vein becomes dislodged and is swept into the lung by the blood flow, where it can block a vessel. In contrast, if this happens in a superficial vein in the leg, the clot must first move in the direction of the deep leg veins, which is less risky.
Who is at risk for deep vein thrombosis?
Elderly men and women have about the same risk of suffering a deep vein thrombosis. In youth, more women are affected by deep vein thrombosis than men. The reasons for this are:
- pre-existing venous disease
- coagulation disorder
- birth control pill usage
- pregnancy
- smoking
- overweight
- operations
- confinement to bed
- unusual physical exertion
How you can prevent deep vein thrombosis (thrombosis prophylaxis)?
Your doctor decides on the type of medication, the dosage, the dosage form and the treatment period.
The objective of all physical measures is to improve venous return flow. There are various ways and means of achieving this objective:
- Medical thrombosis prophylaxis stockings (standardized compression)
- Circular bandaging (non-standardized compression)
- Lower leg, wrap-around compression system
Further examples of physical prophylactic measures are early mobilization, mobilization treatment and elevation of the legs.
Your contact in case of deep vein thrombosis
- General practitioner
- Vein specialist
- Attending physician and nursing staff if hospitalized

How is a deep vein thrombosis treated?
Many patients do not notice severe thromboses at first. This is particularly dangerous because the blood clot that has precipitated the deep vein thrombosis can become dislodged again. If it reaches the lung, it can cause a life-threatening pulmonary embolism.
Treatment gives the highest priority to:
- stopping the thrombosis growing
- removing the thrombosis
- preventing a pulmonary embolism
- preventing post-thrombotic syndrome (permanent damage to the venous valves)
The treatment strategy includes:
- Basic measures, such as correct positioning or mobilization and compression therapy
- Medication to make the blood thinner, such as heparin or Marcumar
- Thrombolysis to break down the blood clot (thrombus)
- Possibly an operation to remove the clot

Compression treatment
After a patient has been diagnosed with deep vein thrombosis, compression garments are prescribed alongside treatment with drugs. These exert mechanical pressure on the veins from the outside. They decrease the diameter of the vein and blood flows back quicker. The pressure on the leg follows a controlled gradient; it is strongest at the ankle and decreases up the leg. Later, doctors will check the extent to which return transport of the blood is still impaired. The doctor can then advise you whether the compression treatment must be continued or whether you can stop wearing the garments altogether.
Pulmonary embolism – when thrombosis is not treated
If a blood clot forms in a deep leg vein, the blood pools, and the vein becomes inflamed. Besides the pain of the venous inflammation, the complications of deep vein thrombosis are particularly serious; if parts of the blood clot become dislodged from the blockage, they can be swept into the lung via the blood. This causes a pulmonary embolism that can be potentially life-threatening because it can prevent blood from reaching your lungs. The danger of a pulmonary embolism is most prevalent in the first three-to-five days of thrombosis.
Compression stockings – treating pulmonary embolisms
Compression stockings are typically prescribed to help prevent deep vein thrombosis – usually after surgery or a stroke when there is a high risk that clots will develop. Compression stockings improve circulation and aid in leg health. When circulation is impaired, blood tends to pool in the lower extremities, causing circulatory problems. Graduated compression helps move blood through veins towards the heart.
.