When the human body is injured, several complex chemical processes occur to help the body recover. Venous blood clots occur naturally when blood cells and strands of protein called fibrin clump together to stop bleeding after a blood vessel has been injured. Eventually, a clot forms a protective scab over a healing wound. When this blood clot does not go away, it is called a thrombus. When clots are in the deep veins like that of the leg, a dangerous condition called deep vein thrombosis (DVT) can occur.
The Centers for Disease Control and Prevention estimates that one third to one half of people who develop DVT will have long-term complications, such as a pulmonary embolism (PE).
“DVT in the leg is the most common type of venous thrombosis, and it can cause serious illness, disability and in some cases death,” says Luis Sanchez, MD, Chief of Vascular Surgery. “Almost anyone can develop this serious and preventable disease, making it incredibly important to know the risk factors and warning signs if you or a loved one develops a DVT.”
To increase information awareness of this serious condition, Washington University vascular surgeons answer patient questions regarding DVT.
DVT: Frequently Asked Questions
What is deep venous thrombosis?
Deep venous thrombosis or deep vein thrombosis (DVT) occurs when a blood clot forms in one or more deep veins, usually in a person’s lower leg and thigh. The clot may interfere with circulation in this area, and it may break off and travel through the bloodstream, or embolize. The embolus could lodge in the brain, lungs, heart, or other areas, causing severe damage to that organ. When DVT breaks off and travels into a lung, it is called a pulmonary embolism (PE) and is often fatal.
What are the symptoms of deep vein thrombosis?
DVT symptoms may only occur in one leg and include pain, tenderness, swelling, or increased warmth or changes in skin color. The pain may begin in the calf and feel like cramping or soreness.
What causes deep vein thrombosis?
Damage to a vein from surgery or trauma and inflammation due to infection or injury are some of the most common causes of DVT.
Risk factors for DVT include prolonged sitting, bed rest, immobilization (such as a long plane ride or car trip), recent surgery or trauma (especially hip, knee, or gynecological injury or surgery, fractures, childbirth within the last six months, and use of medications containing estrogen, such as the birth control pill).
Other diseases also increase the risk of blood clots; these include malignant tumors, polycythemia vera, and inherited or acquired blood-clotting disorders. DVT is seen more commonly in adults over the age of 60 but can occur in any age group.
How is venous thrombosis different from arterial thrombosis?
Understanding how blood flows throughout the human body can help you differentiate between the two main types of thrombosis: venous thrombosis and arterial thrombosis.
Veins carry unoxygenated blood that must flow through the lungs before going to the heart and the rest of the body. Venous thrombosis occurs when a blood clot blocks a vein. Arteries, or blood vessels, take the lead in carrying oxygenated blood from the heart to the brain. When a blood clot blocks an artery, this is called arterial thrombosis.
How do you treat superficial venous thrombosis?
Superficial venous thrombosis (SVT) occurs when the veins just below the skin of the legs, arms, or groin have minor clotting. The skin in these areas becomes red, swollen, or painful after a slight injury and may require treatment. However, these types of clots do not usually travel to the lungs unless they reach the deep veins.
Primary treatments for SVT include the use of warm compresses or non-steroidal anti-inflammatory pain medications (NSAIDs), elevating legs during rest, wearing compression stockings, and maintaining an active lifestyle. Inflammation normally goes away but it may take several weeks for lumps and tenderness to completely subside. In some cases of extensive SVT or in instances where patients are at risk of developing a DVT, patients are given anticoagulants (prescription drugs to help prevent blood clots) or clot busters (drugs that help dissolve blood clots that have formed).
How can you prevent deep vein thrombosis?
Patients can take practical steps to reduce the risk of developing a DVT. Individuals should avoid sitting still and crossing their legs after any type of surgical procedure. If traveling long distances by car, stop every hour to walk around and encourage blood flow. If traveling by plane, stand up and walk in the aisle occasionally; if unable to walk, do heel-toe exercises or rotate feet in a circular motion. Additionally, follow self-care measures to keep risks of heart failure, obesity, diabetes, or any other health issue as stable as possible.
What does deep vein thrombosis feel like?
You may be experiencing a DVT if you feel pain in only one leg. This pain may often start in your calf and feel like cramping or soreness. Additionally, the skin of this leg may be red or discolored and feel warm to the touch. The pain may also worsen when bending the foot. However, some people with a DVT do not experience any symptoms.
Can you check for deep vein thrombosis at home? If so, how?
The only way to diagnose a DVT with 100% certainty is to contact a physician. They may perform a blood test and Venous Doppler ultrasound exam to the leg to visualize the vessels to make a diagnosis.
If you suspect you have developed a DVT, you may also use what is referred to as the Homan’s sign test. To conduct this test, extending your knee in the leg you want to check. Once your knee is in position, you will want someone to help you raise your leg to 10 degrees. Next, have them passively and abruptly squeeze your calf with one hand while flexing your foot with the other. Deep calf pain and tenderness may indicate the presence of DVT.
It is important to note that the Homan’s test has low sensitivity and specificity in diagnosing DVT, but it can be valuable in addition to diagnostic procedures performed by your physician.
Is deep vein thrombosis pain constant?
Yes—The cramping sensations and pain that occur with DVT will persist and even worsen with time. Stretching or “walking it off” like an ordinary charley horse will not ease DVT pain or clear it up.
Can deep vein thrombosis go away on its own?
Though the clots associated with DVT often dissolve on their own, some diagnosed with DVT may need treatment to avoid serious and fatal complications such as pulmonary embolism.
Blood-thinning medications help break up the clots, but surgery may be needed to restore healthy circulation. Surgeries to relieve DVT include open thrombectomy, catheter-directed thrombolysis, and vena cava filter placement.
What does deep vein thrombosis look like?
Physical indicators of DVT include swelling and inflammation of the lower leg and calf, redness, and warmth to the touch.
How long can you have deep vein thrombosis without knowing?
DVT can present with no symptoms or pain, which makes it difficult for physicians to recognize or diagnose. When symptoms of DVT appear, they usually occur suddenly, and patients are encouraged to seek medical attention as soon as they identify anything out of the ordinary. Get immediate health attention if you have pain, swelling, and tenderness in your leg and you develop breathlessness and chest pain as you may have a DVT that developed into a pulmonary embolism.
Can deep vein thrombosis cause a stroke?
DVT may not directly cause a stroke. Strokes occur when the supply of oxygenated blood to the brain is cut off. The arteries, or blood vessels, carry oxygenated blood to the brain from the heart. The blood in your veins, however, is deoxygenated and must flow through the lungs before going to the heart and the rest of the body.
Who do I contact to learn more about deep vein thrombosis?
The Section of Vascular Surgery at Washington University School of Medicine offers the full spectrum of surgical care for patients with DVT and other vascular diseases.
To make an appointment, please contact one of the Vascular Surgery Section’s physicians: