Venous Thrombosis: Treatment

Treating Deep Vein Thrombosis (DVT)

Once a DVT is diagnosed, treatment begins immediately to reduce the risk of the clot extending further or breaking off. Early treatment also reduces the risk of post thrombotic syndrome.

If you have been diagnosed with a DVT, your doctor may recommend treatment at home or in hospital. The type of treatment depends on the location of the clot and the likelihood of further complications. It is important that treatment be started as soon as possible. Patients who receive early treatment will significantly reduce their chances of developing pulmonary embolism (PE).


Heparin & Warfarin

To treat blood clots, doctors use various drugs, including anticoagulants. Standard anticoagulant medications includeheparin and warfarin. Heparin is given either through a vein (intravenously) or as an injection under the skin. Warfarin is given orally as a tablet. Heparin acts immediately, while warfarin takes several days to become effective. Both are usually started at the same time, but heparin is discontinued after warfarin becomes effective. Regular blood tests are required to monitor the effectiveness of warfarin. It is important to take warfarin as directed and to record all dosages.

Two types of heparin are available for treatment of DVT. Unfractionated heparin (UH) is given in hospital, whereas low molecular-weight heparin (LMWH) can be self-injected at home, which usually is more convenient and less expensive. LMWH has the added benefit of not usually requiring periodic blood tests to monitor its effects. An example of low-molecular-weight heparin is enoxaparine.

Contrary to popular belief, anticoagulants do not actively dissolve the clot; they prevent new clots from forming and reduce the risk of PE. In rare cases, clot dissolving (thrombolytic) agents are administered. For patients who are unable to tolerate medications, surgical removal of the clot (thrombectomy) may be performed, as well as insertion of a filter in a major vein that acts like a clot sieve. To minimise any pain, discomfort or complications associated with the treatment of a DVT, you should:

• Elevate the affected leg whenever possible
• Wear graduated compression stockings
• Avoid long periods of immobility.


How long do patients need to be treated for a DVT?

Depending on the underlying condition that caused the DVT, treatment may be needed for as little as four weeks, or for the rest of the patient’s life.

In patients with an obviously reversible cause of a DVT (for example, trauma, after orthopaedic surgery or prolonged bed rest), four to six weeks of therapy are usually adequate. The risk of a recurrent DVT in these patients is very low.

In patients with an identified cause of DVT that cannot be reversed (for example, cancer, inflammatory bowel disease or inherited conditions), therapy should continue for at least six to 12 months, and may need to be continued indefinitely.

Patients with no identifiable cause of their DVT have been shown to experience a high incidence of recurrent blood clots if they are treated for three months or less. Most physicians, therefore, recommend at least six months of anticoagulant therapy for these patients.

With treatment, the clot stabilises and attaches firmly to the wall of the vein. The risk of the clot breaking off and travelling to the lungs, therefore, decreases over time.