Deep vein thrombosis is the formation of blood clots (thrombi) in the deep veins. These blood clots occur most often in the deep veins of the legs or pelvis but can also occasionally develop in the arms. The clots cause a slowing in the return of blood to the heart or can completely block a vein resulting in a thrombosis. Pulmonary Embolism is another rare possibility in predisposed individuals.
Three main factors (known as Virchow’s triad) can contribute to deep vein thrombosis.
- Injury to the vein’s lining
- An increased tendency for blood to clot
- Slowing of blood flow
Veins may be injured during surgery, by the injection of irritating substances, or by certain disorders, such as Buerger’s disease. They also may be injured by a clot, making formation of a second clot more likely. Some disorders, such as cancer and certain inherited disorders, cause blood to clot when it should not. Some drugs, including oral contraceptives, estrogen therapy, or drugs that act like estrogen (such as tamozifen and raloxifene), can cause blood to clot more readily. Smoking is also a risk factor. Sometimes blood clots more readily after childbirth or surgery. Among older people, dehydration commonly causes the blood to clot more readily and can therefore contribute to deep vein thrombosis. Also, during prolonged inactivity when the legs are not moving normally, blood flow slows because the calf muscles are not squeezing the blood back toward the heart.
- Advanced age
- Tobacco use
About half of the people with deep vein thrombosis have no symptoms at all. In other people, chest pain or shortness of breath caused by pulmonary embolism may be the first indication that something is wrong. If a deep leg vein is involved, the calf swells and may be warm to the touch and quite painful. The ankle, foot, or thigh or the arms may also swell, depending on which veins are involved.
Leg swelling, aching or throbbing, skin changes or skin discoloration, ulcers and varicose and/or spider veins are the most often noted symptoms.
Although the risk of deep vein thrombosis cannot be entirely eliminated, it can be reduced in several ways. People who are at risk should try these suggestions:
- Pump the muscles in the calf of your leg by flexing and extending your ankles about 10 times every 30 minutes
- During long trips you should get up and walk for a couple of minutes every 2 hours
- Elevate your legs when possible
- Wear compression stockings as recommended by your physician
- Anti-coagulants as prescribed by your physician
- Endovenous Laser Ablation, Radio frequency ablation, microphlebectomy and Ultrasound guided sclerotherapy are minimally invasive in-office procedures
- Thrombolysis and venography are minimally invasive treatments done in a hospital setting
- Prevention of pulmonary embolism
- Prevention of recurrent DVT
- Prevention of post-phlebetic or post thrombotic syndrome (edema pain, increased pigment, hardening of skin ulceration and itchiness)