Deep venous thrombosis (DVT) involves the formation of a blood clot in a deep vein. Most DVTs occur in leg or hip veins, but they can also occur in other parts of the body. Generally speaking, blood clots that occur in thigh veins tend to be more serious than blood clots affecting veins in the lower leg. If a DVT breaks off and travels through your bloodstream, it can become lodged in your lung. The resulting condition, called a pulmonary embolism, is very serious and can be fatal. Blood clots can also occur in superficial veins, or veins that are close to the skin's surface. These types of blood clots are called superficial venous thromboses or phlebitis. Blood clots in superficial veins are typically considered less serious than DVTs because they cannot travel to the lungs.
There are many factors that can increase your risk for developing DVTs, including:
Only about half of the people with DVT or pulmonary embolism have symptoms, which may include:
Unfortunately, some people only find out they have a DVT after the clot has moved from the leg and traveled to the lung, resulting in pulmonary embolism. If you have symptoms of a pulmonary embolism or DVT, it is crucial that you see a doctor immediately.
The main goals in treating DVTs are to:
There are several medications used to treat and/or prevent DVTs. Surgery is sometimes recommended for patients at great risk for recurrent embolism.
Anticoagulants (sometimes called blood thinners) decrease your blood's ability to clot. They are used to stop clots from getting bigger and to prevent them from forming. Anticoagulants do not break up blood clots that have already formed - your body's natural system will dissolve the clot. Anticoagulants come in pill form and can also be injected. Thrombolytics are medications given to quickly dissolve a blood clot. They are used to treat large clots causing severe symptoms. Because thrombolytics can cause sudden bleeding, they are used only in life-threatening situations. Thrombin inhibitors are new medications that interfere with the clotting process. They are used in treating certain types of clots, including those affecting patients who cannot take the anticoagulant, heparin. Venous Filters (also called vena cava filters) are used with patients who cannot take medications to thin their blood, or for those who are taking blood thinners and continue to develop clots. The filter can prevent blood clots from moving from leg veins to the lungs, thus preventing pulmonary embolism. The filter is inserted inside a large vein called the vena cava, and is capable of catching clots as they try to move through the body and to the lungs. Although this treatment will prevent pulmonary embolism, it will not stop additional clots from developing.
Preventing blood clots among patients who are at risk is very important. Becoming active as soon as possible following surgery or remaining somewhat active during a prolonged illness can reduce the risk of developing blood clots in the lungs. Subcutaneous heparin therapy (low doses of heparin injected under the skin) may be used for those on prolonged bedrest. Another preventive measure includes wearing compression stockings, which fit snugly around the legs and help circulate blood.