Blood clot in leg? Deep venous thrombosis is a clot in a vein, usually in the lower limbs— here its symptoms, causes, and treatment.
Deep vein thrombosis by itself is not a major problem, although its main complication: pulmonary embolism, can be life-threatening. Therefore, preventing this condition by timely treatment is crucial in reducing its impact on people’s life.
Learn everything about deep venous thrombosis directly from a doctor in the lines below.
What is deep venous thrombosis or blood clot in a leg?
Deep venous thrombosis (DVT) is the name for blood clot formation in a vein. It usually occurs in a vein from the leg, the thigh, or the pelvis. Veins are the blood vessels (like long tubes) that carry blood from the organs back to the heart. It can also happen in the arm, but it is uncommon. Clots occur naturally to prevent blood loss from an injury. However, in DVT, clots occur inside veins without injuries. In this case, the clot can stop normal blood flow.
The risk of DVT is not very high in general, but it can be important in patients with risk factors. See below for more on this topic.
Deep venous thrombosis has a good outcome when caught early. Without treatment, DVT can cause severe and disabling complications or even death.
Pulmonary embolism (PE) is the most common DVT complication. This happens when the clot or a piece of it breaks and travels to the lung vessels. There is more information on PE in the lines below. Deep vein thrombosis and pulmonary embolism together are called Venous Thromboembolism (VTE). This means that VTE can refer to PE or DVT. Almost all cases of PE have an underlying vein thrombosis.
What are the symptoms of DVT?
The two most important symptoms of deep venous thrombosis are pain and swelling. Symptoms usually present in only one limb. When the clot occurs in a vein closer to the heart, swelling of both legs is possible. When this happens, doctors might mistake it for other heart, kidney, or liver diseases. Swelling can present with redness or warmth on the skin.
The presence of symptoms depends on the size and the amount of obstruction. Another possible symptom is tenderness. However, it can also indicate other diseases. Pain and tenderness usually happen in the calf or the middle thigh. When the pain appears in other areas, DVT is not the most likely diagnosis.
Doctors frequently perform a test where they raise the leg and push the foot upwards. When calf pain appears during the test, the patient has a positive Homans sign. This was a physical test highly suggestive of DVT in the past, although nowadays, it is not very useful in diagnosing DVT.
Another possible finding is “superficial thrombophlebitis.” This is a superficial vein that has a hard texture. Doctors find it while inspecting the legs. It feels like a cord underneath the skin. It is relevant when the patient doesn’t have other varicose veins. Varicose veins are distended superficial veins in the lower limbs. There’s more on this below.
Changes in leg color are also possible. Red or purple tones are most common, but severe cases can present with a pale leg.
It is hard to diagnose or rule out DVT just based on the symptoms. Approximately half of the patients lack symptoms, and others with symptoms have negative test results. If the disease progresses in a patient without symptoms, a pulmonary embolism is possible.
Pulmonary embolism symptoms include:
- Difficulty breathing.
- Chest pain.
- The uncomfortable sensation of rapid heartbeats.
- Cough with or without blood.
Symptoms normally appear in a sudden and disruptive way.
What are the risk factors for DVT or blood blot in the leg?
Many factors can put someone at risk for DVT. Fractures and muscle injuries can damage veins directly, causing blood inside them to clot. Major surgery in the abdomen, pelvis, hips, and legs can also cause direct vein damage.
Veins need moving muscles to function properly. Slow blood flow can also cause clot formation inside the veins. Major surgery has a high association with bed rest, which can cause slow blood flow. People at bedrest for other medical reasons also have a higher risk of DVT. People wearing a cast to recover from a fracture also have increased clotting risk. Travelers in cars or airplanes who spend a long time sitting (more than four hours) are also at risk of VTE.
Hormones can increase the risk of DVT for some patients. Women on birth control pills and menopausal women taking hormone supplements are more likely to develop DVT. Besides, hormone changes in pregnancy put pregnant women at a higher risk even three months after giving birth.
Chronic illnesses like heart or lung diseases, cancer, and inflammatory bowel disease (Crohn’s disease and Ulcerative colitis) are important risk factors. Risk also increases with age, obesity, previous VTE or family history of VTE, and genetic clotting disorders.
Smoking slightly increases the chances of VTE alone. When considered with other risk factors, it becomes more significant.
Sometimes, having one risk factor alone is not enough to develop DVT. Doctors carefully evaluate every patient’s situation to determine whether it is a probable diagnosis. A healthcare provider is the best to address any doubts regarding this topic.
Will I suffer a thrombus if I have varicose veins?
It is important to differentiate two types of veins on the legs—superficial ones that run beneath the skin and a deep group where DVT usually happens.
Varicose veins are superficial dilated veins in the legs. They are usually visible through the skin due to their bluish color. In some cases, they appear as bumps or tortuous lines.
Veins have a weak wall, and blood travels against gravity without something that pushes strongly. Valves in the veins can be weak or wounded, either due to aging or some other disease. All this causes veins to dilate, becoming varicose.
In reality, varicose veins, by themselves, do not increase the risk of blood clots. But in combination with other factors such as tobacco, obesity, or a long plane trip, the danger increases. Thus, if someone has varicose veins, it is very important to take these factors into account.
Doctors can diagnose varicose veins just by looking at them. Most patients come to the medical consult with the diagnosis of varicose veins already made since they are visible. Some patients may have significant symptoms like pain or discomfort in their legs and not have varicose veins.
In this situation, an expert must determine where is the source of the pain. It could be chronic venous insufficiency or another potential disease. In both cases, the most useful diagnostic method for evaluating the patient is an imaging exam, color echo-Doppler.
The treatment of chronic venous insufficiency and varicose veins cover a broad spectrum of possibilities. These possibilities involve pharmacological treatments and surgeries. In the beginning, doctors will suggest a conservative approach to almost all patients. But, as they become more serious, treatments such as sclerotherapy and surgery become necessary.
How can I prevent deep venous thrombosis or a blood clot in the leg?
Almost all prevention strategies aim to reduce risk factors. Things like age, history of other diseases, genetic conditions, or pregnancy are difficult to change. Still, body weight, inactivity, or smoking are controllable.
If someone has had recent surgery, their doctor will indicate a proper bedrest time. After that, progressive reincorporation to activity is essential. In cases where DVT is likely because of other risk factors, doctors can prescribe anticoagulant medicine to prevent blood clotting.
Some patients may benefit from medical compression stockings. These are stockings that cover the leg to improve blood circulation in the veins.
When traveling for long periods, avoid sitting for the entire trip. If possible, short walks are ideal. If not, movements to lift your heels and your toes are a good option. Keep moving at least every two hours. Studies indicate that aisle-seating passengers have a lower risk of developing DVT.
After one episode of VTE, a second episode is more likely. In this case, anticoagulant medicine is very helpful to prevent venous clot formation. A doctor should always be aware of the patient’s situation and prevent possible DVT episodes.
How do doctors diagnose DVT or a blood clot in the leg?
Doctors may rely on many factors to diagnose deep vein thrombosis, including medical history, physical examination, and certain tests. It is important to know if you have had a recent surgery or other diseases such as cancer or spine injury. Doctors will also ask about symptoms and check at the physical exam for thrombosis signs, such as swelling and redness of the legs. Then, they will check the lungs, heart, and blood pressure.
Duplex ultrasound is one of the primary or most commonly used tests recommended by doctors. This study would help to detect the presence of clots or thrombi in deep veins. This test uses sound waves to produce images of the blood flow throughout the blood vessels. Ultrasound is a secure, painless exam. Doctors will place a transducer, or rod-shaped device, on the legs, enabling them to see blood flow changes on a video screen.
When this latter study does not reveal an accurate diagnosis, your doctor may order venography. In this exam, the interventional radiologist injects a contrast medium into the foot or ankle’s large veins. The contrast acts as a dye that allows the vessels to be visible in the radiography. If they detect sluggish circulation on the radiograph, it is a warning of the presence of a clot.
Your doctor will often order a blood test called a D-dimer. This test measures a substance released when blood clots dissolve. If the D-dimer concentration is high in the blood, it is suggestive that there is a clot in the deep veins.
Physicians can diagnose DTV when complications such as pulmonary embolism have occurred. Likely, a doctor might incidentally discover a blood clot while reviewing an MRI or CT scan performed for other conditions.
How is a blood clot in the leg or DVT treated?
The goal of the treatment for DTV is to stop clotting and prevent complications, such as pulmonary embolism. That is why once diagnosed; it is advisable to start treatment immediately. The usual treatment for deep venous thrombosis is an anticoagulant medication. These drugs come as pills, or injections, either directly into de bloodstream or in small injections under the skin.
Anticoagulants work by decreasing the blood’s ability to form clots. This prevents already existing clots from getting bigger. Also, they help prevent the formation of new clots.
People also call anticoagulants a “blood thinner.” Among the injectable anticoagulant medicines, the most common are heparin and fondaparinux. While warfarin, rivaroxaban, and apixaban stand out among the orals. Treatment can last for months. Thus, since it makes it harder for the body to form clots, it increases bleeding risk. This is why doctors will routinely schedule blood tests to ensure that you receive an adequate dose. Likewise, it would be best to inform your doctor about unusual bleeding or some other signs such as bruising.
For more serious cases, the doctor will recommend thrombolytics, a family of medicines that rapidly dissolve clots. This type of medication has a greater chance of bleeding as a side effect.
When anticoagulants and thrombolytics are not successful enough, specialists can insert a vein filter. This is a simple surgical procedure that involves inserting a filter into the inferior vena cava. The inferior vena cava is a large vein that brings blood from the lower body to the heart. This filter captures the emboli before they can reach the lungs or brain. This measure alone can’t prevent DVT, but it prevents pulmonary embolism.
If I take Aspirin, can I get DVT?
Aspirin, or its medical name: acetylsalicylic acid (ASA), significantly affects platelet function. Platelets are a type of blood cell that helps in the formation of blood clots, especially during injuries. Many patients take Aspirin daily for many reasons, like previous heart attack history.
Aspirin is useful to prevent heart attacks because the platelets play an important role in arterial clot formation. In contrast, platelets seem to play a secondary role in the development of the DVT blood clot. The main factor that puts people at increased risk is slow blood flow. In this sense, Aspirin is not the ideal medication to prevent VTE.
Despite this, Aspirin is the target of investigations in the field of joint replacement surgeries. Some scientists have found Aspirin to be effective to some degree in preventing DVT. Doctors think that Aspirin might be beneficial in some cases. Nonetheless, this situation should be directly addressed by a physician and their patient. Every patient is different, and the treatments are not the same for everyone.
What happens if a blood clot in the leg goes untreated?
After having a DVT, the majority of patients sooner or later develop permanent leg discomfort. It is a pain, cramping, tingling, scratching, heaviness, leg swelling, or a combination of these. This is known as post-thrombotic syndrome (PTS) and is the most common complication after thrombosis. Pulmonary embolism, recurrent DVT, and paradoxical emboli are other complications.
The damage to the veins results in venous hypertension, or higher than normal blood pressure in the veins. Leg veins have valves. They are like tags that prevent blood flow in the wrong direction. This rise in pressure will affect the valves in the veins. This situation causes the blood to pool at the site, often causing permanently dilated veins. It’s a long-term complication that appears months or years after the initial DVT episode. Patients with the post-thrombotic syndrome have trouble walking, affecting their everyday activities. PTS patients report symptom relief when they elevate the leg or wear graded compression stockings.
About 5-10 % of patients with PTS experience venous leg ulcers. These are like sores in the skin of the leg. They require medical attention. Sometimes they get infected and require antibiotic treatment. Severe venous ulcers require surgery to remove damaged tissue.
When a blood clot in a leg vein breaks down and passes into the bloodstream, it becomes an embolus. If the embolus blocks the supply of blood to the lungs, the disease becomes a Pulmonary embolism. Pulmonary embolism normally manifests its symptoms rapidly and threatens the patient’s life.
Sadly, around 2 out of 5 patients with symptoms of DVT have silent PE. Conversely, patients can have PE without DVT symptoms. This is why everyone should be mindful of the signs and risk factors for seeking medical attention as soon as possible. If the clot is small, a person may recover from PE with proper care. Without medical care, a PE can cause severe lung damage or even death. PE causes approximately 300,000 deaths annually solely in the United States.
Can a blood clot in the leg or deep venous thrombosis cause a stroke? How about a heart attack?
There are two main types of blood vessels: arteries and veins. As it says in the lines above, veins take blood from the organs to the heart. Oppositely, arteries pump blood from the heart to the organs of the body. Strokes occur when the blood supply to the brain stops. Similarly, a heart attack happens when the blood supply to the heart is interrupted. This situation happens in the arteries.
Blood flow interruption can occur because of a fat plaque, as mentioned before, or because of an arterial clot. However, DVT clots appear in veins; and for them to travel to the brain or heart arteries is not possible. When a clot causes a heart attack or a stroke, the clot’s formation happens in arteries.
In some cases, a stroke can happen when arteries break, and blood doesn’t reach its destination in the brain. This situation receives the name of hemorrhagic stroke. Some types of anticoagulant medication might increase the risk for this type of stroke. Close doctor monitoring is extremely important when receiving anticoagulant therapy after a VTE.
Still, keep in mind that in very odd situations, DVT can cause a stroke. This situation takes place when there are abnormal heart walls. It is known as paradoxic emboli. People with these heart defects (atrial septal defect is the most common) are at risk of having a blood clot migration from the vein to the artery circulation. Therefore, allowing it to reach the brain instead of its usual final destination, as the lungs are.
What could it be if it’s not venous thromboembolism?
There are many other diseases that doctors can clinically confuse with deep vein thrombosis. Examples of this are muscle injuries or bacterial skin infections. Also, the inflammation of superficial veins can look similar to superficial thrombophlebitis present in some DVT patients.
Infectious cellulitis, also known as bacterial cellulitis, occurs when bacteria get into the skin, infect the deeper layers, and cause intense redness of the skin, irritation, and inflammation of the affected region. Nevertheless, infectious cellulitis typically disappears with the use of oral antibiotics.
Other causes of leg pain and swelling include arthritis, a bruise, kidney failure, liver disease, or problems with the arteries supplying blood to the leg.
On the other hand, heart attacks and pneumonia may have signs and symptoms close to those of PE. Therefore, when diagnosing these disorders, special procedures aim to detect or discard clots in the lungs’ blood vessels.
A heart attack occurs when the blood supply to the heart is blocked. The blockage is most often a buildup of fat, and other substances, which form a plaque in the coronary arteries. The coronary arteries supply blood to the heart. Heart attacks can cause chest pain that may be similar to that of PE.
Aside from that, pneumonia is an infection that affects one or both lungs. The signs and symptoms of pneumonia depend on several factors, such as the germ type that caused the infection. Moderate signs and symptoms are usually similar to a cold and can include chest pain and difficulty breathing (shortness of breath). Pneumonia usually presents with cough and phlegm, fatigue, and fever. Not all pneumonia cases are similar to a pulmonary embolism, but doctors might consider this a possible diagnosis.
Do you think you have a blood clot in the leg or DVT?
If you think you have a blood clot in the leg or deep vein thrombosis, it is important to seek healthcare assistance immediately. Still, this is a Deep Venous Thrombosis Symptoms Checker. It gathers the most important signs, symptoms, and risk factors for the disease. Therefore, the tool will tell anybody who uses it the likelihood of their symptoms because of this condition or persons at higher risk of having it. Using the tool is free and would only take a few minutes.