Quick Summary
Deep vein thrombosis (DVT) is a serious vascular condition that affects thousands of Americans every year. It is caused by blood clots in the veins deep in the legs. Typical symptoms include leg pain and leg swelling. These blood clots may also break off into your lungs, causing shortness of breath and even death. Treatment involves starting on a blood thinner right away and finding out why you are having DVTs. Some patients may qualify for clot removal procedures, depending on the location and severity of their symptoms.
What are Deep Veins?
Our body has two kinds of blood vessels, arteries and veins. The arteries send oxygenated blood flow to your organs and tissues via high pressure supplied by the heart. The veins do the opposite by returning the deoxygenated blood back to the heart.
In your legs and lower pelvis, the majority of the blood flows back to the heart by large veins that are surrounded by your leg muscles. We call these veins “deep veins” because they are located deep in the body relative to other surface veins. Deep veins include the tibial veins, popliteal veins, femoral veins, and iliac veins. The blood flow eventually flow into the inferior vena cava (IVC), which is a large central vein in the abdomen. The IVC then returns the blood flow from the lower half of the body back to the heart and lungs. Because these deep veins are highways to the heart and lungs, any blood clots within the deep veins poses a risk to the cardiovascular system.
What is Deep Vein Thrombosis?
Deep vein thrombosis, or DVT for short, is a blood clot formed in one or more deep veins. A DVT can start small and grow in size over time, obstructing blood flow. This can cause significant swelling and pain in a limb. The lower extremities are most commonly affected. Furthermore, a DVT break off and flow into the heart and lungs, causing a serious condition called pulmonary embolism (PE). A PE can lead to difficulty breathing, heart strain, and even death.
What Causes DVT?
What Are The Symptoms of DVT?
DVT can be caused by both medical and physical issues. Classically, blood clots form when one of these conditions are met:
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- Blood flow stagnation (stasis)
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- Trauma to the veins
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- Increased thickness of the blood (hypercoagulable state)
Blood stagnation can be caused by physical inactivity. A commonly quoted instance is a long plane ride, where hours long sitting in one position decreased the muscle pump activity in your legs, causing stagnant blood to become clots. Physical inactivity may also be more prevalent in more elderly people or people who are hospitalized.
Trauma to the veins can cause blood clots. If the vein is physically injured in anyway, the body reacts by forming clots to prevent it from bleeding. While this is a good thing from evolutionary standpoint, sometimes this process works too well and too extensive, causing further problems and symptoms.
Lastly, any medical condition that causes blood to thicken also predisposes a person to form DVT.
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- Family history of blood clots is a risk factor as a person may carry genes that predisposes them to DVT
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- Conditions such as autoimmune diseases, cancer, of infection may increase inflammation in the body and prompt DVT development.
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- Hormones during pregnancy or from birth control are a known risk factor
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- COVID-19 infection has been associated with some serious DVT clotting complications
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- Obesity and tobacco are also risk factors for DVT
When blood clots form in the leg, symptoms can range from asymptomatic to severe. If clot burden is small, a person may not feel anything and diagnosis is made incidentally when they undergo a medical test for something. If the clot burden is more extensive, the patient may develop leg swelling, pain, and discoloration. The most feared issue with DVT is when the clot breaks off and travels to the lungs. This is called pulmonary embolism (PE) and the patient may feel chest pain and/or shortness of breath. If the PE is very large, it could impede blood flow to the heart and death may ensue if emergent treatment is not provided.
How Do You Treat DVT?
Treatment for DVT typically starts with medication to thin the blood so that the clots do not grow any further. This may be enough if the clot burden is small and symptoms are mild. When DVT is extensive and/or if the symptoms are severe, adjunctive procedural treatments may be required. These may include physically breaking and suctioning out the clots or dripping lysing medications into the veins to dissolve the clots. In many cases, a combination of techniques is used to achieve effective results.