Deep Vein Thrombosis

Also called a DVT, Thrombophlebitis, Phlebitis and Venous Thrombosis

A deep vein thrombosis is a blood clot that occurs in the deep veins of the body. The most common spot for deep vein thrombosis is the calves of the legs, the thigh and the pelvic veins deep within the pelvis. The blood clot can remain within the vein or can break off and go to the lungs or the brain, causing a pulmonary embolism or stroke. A heart attack can be a secondary result of a deep vein thrombosis.

Risk factors for deep vein thrombosis are sitting still for a long period of time, such as in an airplane or car ride, having recently had surgery, being immobile for any period of time and being on estrogen replacement therapy. Injury to the deep veins can increase the risk of a DVT. Being hospitalized can lead to a DVT as can pregnancy and obesity. Being on birth control pills can increase the risk of deep vein thrombosis and there can be a genetic reason for having a DVT. Smoking predisposes one to a DVT and those with polycythemia vera (excess red blood cells) and cancer can get deep vein thromboses. Leg fractures predispose a person to getting a DVT and procedures on the vein itself can cause the condition.

Deep vein thromboses are not dangerous if they remain where they are. The problem is that the clot often breaks off and travels to the lungs, the heart or the brain. This can cause a pulmonary embolus, a heart attack or a stroke, respectively. Superficial blood clots in the legs do not cause the same problem as when the blood clots in the deep veins. The symptoms are different when comparing deep vein thrombosis and superficial vein thrombosis.

Symptoms of a superficial vein thrombosis or thrombophlebitis include redness to the skin of the legs, warmth, itching, tenderness and swelling of the affected area. The area involved can be seen visibly and treated with local heat and blood thinners. Symptoms of deep vein thrombosis include swelling of the entire leg, redness of the leg, pain on extending the foot (a positive Homan's sign) and warmth of the entire lower leg. There can be edema of the leg from lack of blood flow to the affected area. Deep vein thrombosis may have no symptoms at all, which makes it a very dangerous disease to have.

The treatment of deep vein thrombosis can be as simple as using warm compresses to dissolve the clot and compressing the leg to keep the clot from growing. It can also be as complex as using blood thinners and clot busting drugs to break up the clot medically. Heparin is often used to thin the blood so the deep vein thrombosis can dissolve gradually on its own. If clot busting drugs are used, such as TPA, the clot is actively broken up and dissolves more quickly. Nonsteroidal anti-inflammatory medications are used also to thin the blood and to ease the pain of a superficial or deep vein thrombosis.

Deep vein thromboses that happen below the knee rarely break off and embolize to other body areas. Doctors can use therapeutic measures and follow the clot with an ultrasound of the leg done serially over time until the blood clot resolves. If they extend above the knee, the chances of blood clots breaking off and causing damage to other body areas are much higher and anticoagulation needs to be more aggressive. The problem occurs when a person has recently had surgery or a stroke or other condition that precludes the use of a blood thinner. Then only watchful waiting is able to be done.

When a person's blood is made thin enough with heparin intravenously, the individual is started on Coumadin or warfarin, which is an oral drug that keeps the blood thin for a longer period of time. People with repetitive deep vein thrombosis need to be on chronic Coumadin therapy.

Surgery is a rarely used treatment for deep vein thrombosis. It is done if blood thinners can't be used or if there is clotting in spite of being on anticoagulants. Surgeons go in and remove the clot manually.