Deep vein thrombosis is most common in adults over age 60. But it can occur at any age. When a clot breaks off and moves through the bloodstream, it is called an embolism. An embolism can get stuck in the blood vessels in the brain, lungs, heart, or another area, leading to severe damage.
Blood clots may form when something slows or changes the flow of blood in the veins. Risk factors include:
- A pacemaker catheter that has been passed through the vein in the groin
- Bed rest or sitting in 1 position for too long, such as plane travel
- Family history of blood clots
- Fractures in the pelvis or legs
- Giving birth within the last 6 months
- Pregnancy
- Obesity
- Recent surgery (most commonly hip, knee, or female pelvic surgery)
- Too many blood cells being made by the bone marrow, causing the blood to be thicker than normal (polycythemia vera)
- Having an indwelling (long-term) catheter in a blood vessel
Blood is more likely to clot in someone who has certain problems or disorders, such as:
- Cancer
- Certain autoimmune disorders, such as lupus
- Cigarette smoking
- Conditions that make it more likely to develop blood clots
- Taking estrogens or birth control pills (this risk is even higher with smoking)
Sitting for long periods when traveling can increase the risk for deep vein thrombosis. This is most likely when you also have 1 or more of the risk factors listed above.
Deep Vein Thrombosis Symptoms
Deep vein thrombosis mainly affects the large veins in the lower leg and thigh, most often on 1 side of the body. The clot can block blood flow and cause:
- Changes in skin color (redness)
- Leg pain
- Leg swelling (edema)
- Skin that feels warm to the touch
Deep Vein Thrombosis Treatment
Early in treatment, blood thinners are given to keep the clot from growing or breaking off and traveling to the lung and causing a life-threatening pulmonary embolism by blocking the oxygen supply causing heart failure. Contrary to popular belief, blood thinners (anticoagulants) do not actively dissolve the clot, but instead prevents new clots from forming. Over time, the body will dissolve the clot, but often the vein becomes damaged in the meantime. To prevent permanent leg damage, patients can get catheter-directed thrombolysis treatment.
Catheter-directed thrombolysis is performed under imaging guidance by interventional radiologists. This procedure is designed to rapidly break up the clot, restore blood flow within the vein, and potentially preserve valve function to minimize the risk of post-thrombotic syndrome.
It is important for deep vein thrombosis patients to be evaluated to determine if catheter-directed thrombolysis is needed to remove the clot. This treatment is highly effective when performed within 10 days after symptoms begin.
In patients in whom this is not appropriate and blood thinners are not medically appropriate, an interventional radiologist can insert a vena cava filter, a small device that functions like a catcher's mitt to capture blood clots but allow normal liquid blood to pass.
In rare cases, you may need surgery if medicines do not work. Surgery may involve:
- Placing a filter in the body's largest vein to prevent blood clots from traveling to the lungs
- Removing a large blood clot from the vein or injecting clot-busting medicines