Understanding Deep Vein Thrombosis

Understanding Deep Vein Thrombosis

Deep vein thrombosis (DVT) is a condition in which a blood clot or thrombus forms in a deep vein. A blood clot is most common in the leg. But it can develop in a large vein deep inside the leg, arm, or other part of the body. Part of the clot called an embolus can separate from the vein. It may travel to the lungs and form a pulmonary embolus (PE). This can cut off blood flow to part of the lung or to the entire lung. A PE is a medical emergency and may cause death. Healthcare providers use the term venous thromboembolism (VTE) to describe the 2 conditions, DVT and PE. They use the term VTE because the 2 conditions are very closely related. And, because their prevention and treatment are closely related.

Over time, a blood clot can also permanently damage veins. To protect your health, a blood clot must be treated right away.

How DVT develops

The deep veins of the legs are located in the muscles. These help carry blood from the legs to the heart. When leg muscles contract and relax, blood is squeezed through the veins back to the heart. One-way valves inside the veins help keep the blood moving in the right direction. When blood moves too slowly or not at all, it can pool in the veins. This makes a clot more likely to form.

Cross section of muscle and vein showing open valve with arrow showing blood moving up. Cross section of varicose vein with thrombus and emboli.

Risk factors

Anyone can get a blood clot. These risk factors make a blood clot more likely to happen:

  • Being inactive for a long time, such as when you’re in the hospital, or traveling by plane or car

  • Injured vein due to an accident, a broken bone, or surgery

  • Past blood clots 

  • Personal or family history of a blood-clotting disorder

  • Recent surgery

  • Cancer and certain cancer treatments

  • Smoking

Other things can also put you at higher risk for a blood clot. They include:

  • Being older than 60

  • Pregnancy

  • Taking birth control or hormone replacement

  • Having other vein problems

  • Being a person of size

Common symptoms

A blood clot doesn't always cause obvious symptoms. If you do have symptoms, they often happen suddenly. They may include:

  • Pain, especially deep in the muscle

  • Swelling

  • Aching or soreness

  • Red or warm skin

  • Fever

When to call your healthcare provider

Call your healthcare provider if you have any of the common symptoms listed above. In addition, call your provider if you have symptoms of bleeding such as:

  • Blood in the urine
  • Bleeding with bowel movements
  • Bleeding from the nose, gums, a cut, or the vagina

Call 911

Call 911 if you have symptoms of pulmonary embolism such as:

  • Trouble breathing

  • Fast heartbeat

  • Chest pain

  • Sweating

  • Coughing (may cough up blood)

  • Fainting

If you take medicine to help prevent blood clots, you have an increased risk of bleeding. Also call 911 if you have heavy or uncontrolled bleeding.

Diagnosing DVT

Your healthcare provider will start with questions about your symptoms and health history along with a physical exam.

Diagnostic tests include:

  • An imaging test called a duplex ultrasound. This test uses sound waves to create pictures of veins and blood flow.

  • Blood tests. These are done to check for clotting and other problems.

If your provider thinks you may have pulmonary embolism, more testing will be done.

Treating DVT

Treating a blood clot may include:

  • Medicine to thin the blood and prevent pulmonary embolism and other complications.

  • Staying in the hospital. This may or may not be needed.

  • Surgery in some cases.

Preventing DVT

Many people who are in the hospital are at an increased risk of developing blood clots. So, preventing blood clots is an important part of in-hospital care. The care may include getting out of bed regularly, taking medicine, or using special therapies or devices. Other factors and conditions may increase the risk of blood clots. Review your risk with your healthcare provider.

What is percutaneous transcatheter treatment of deep vein thrombosis (DVT)?

Percutaneous transcatheter treatment is 1 type of therapy for deep vein thrombosis (DVT). DVT is a blood clot that forms in a large vein deep in the body. It happens most often in a leg. The procedure uses a thin, flexible tube called a catheter to help remove the blood clot.

During the treatment, a healthcare provider will insert a catheter into a blood vessel in your groin. Then the provider will move the tube through your blood vessels until it reaches the site of the clot. Percutaneous means that the procedure is done through a small puncture in the skin instead of a large incision.

Your healthcare provider might use 1 of several types of percutaneous transcatheter treatments. The catheter may be used to send clot-dissolving medicine to the DVT. This can help break up the clot. Or your healthcare provider might use small tools to help break up the clot. In some cases, a tiny balloon or metal, mesh coil (stent) is inserted in the vein to help hold it open.

Why might I need percutaneous transcatheter treatment of DVT?

You may need this procedure if you have DVT. DVT can lead to possible problems, such as:

  • Blood clot that moves to the lung and causes breathing trouble and risk of death (pulmonary embolism)
  • Leg swelling and pain
  • Enlarged veins (post-thrombotic syndrome)
  • Loss of the limb (rare)
  • Shock and death (very rare)

Your healthcare provider might advise this procedure if certain conditions apply to you. These include if you:

  • Are having symptoms from your DVT
  • Are at high risk of pulmonary embolism
  • Have a clot above your knee
  • Have a very large and severe clot
  • Want to decrease the risk of post-thrombotic syndrome

Transcatheter treatment is not the only kind of treatment for a blood clot. Your DVT has to fit certain criteria for this treatment to be an option. Your healthcare provider will tell you if this procedure is right for you. Many people with blood clots are treated with medicines called blood thinners. These are given as an injection or through an IV. They can prevent a blood clot from getting larger.

All treatments for blood clots have their own risks and benefits. Ask your healthcare provider if surgical thrombectomy might be a good choice for you. You might find it helpful to talk to a healthcare provider who specializes in blood vessel problems. This type of provider is called a vascular specialist.

What are the risks of percutaneous transcatheter treatment of DVT?

All procedures have risks. The risks of this procedure include:

  • Excess bleeding that can be bad enough to cause death
  • Infection
  • Damage to the vein at the site of the blood clot
  • Reaction to anesthesia
  • The stent detaching
  • Clot breaking off and travelling to the lungs (pulmonary embolism), causing breathing problems or death

There is also a risk that your blood clot will form again. Your own risks may vary depending on your general health and how your blood clots. They may also vary depending on how long you’ve had the clot and where it is in your body. Talk with your healthcare provider about all your concerns and questions.

How do I get ready for percutaneous transcatheter treatment of DVT?

Before the procedure, you will need to sign a consent form. This gives your healthcare provider permission to do the procedure. It also states that you fully understand the risks and benefits of the procedure and have had all your questions answered. You will also be asked to sign an anesthesia consent form for permission to get anesthesia. Before you sign any consent forms, be sure all your questions are answered.

Ask your healthcare provider how to prepare for your procedure. Tell your provider about all the medicines you take. This includes over-the-counter medicines, such as aspirin, vitamins, and herbal supplements. You may need to stop taking some medicines ahead of time, such as blood thinners. If you smoke, you’ll need to stop before your procedure. Talk with your healthcare provider if you need help to stop smoking.

Before the procedure, tell the medical team if you:

  • Have any allergies
  • Have any recent changes in your health, such as fever
  • Are pregnant, or could be
  • Have ever had a problem with anesthesia

You may need some tests before the procedure, such as:

  • Ultrasound, to measure blood flow in the leg and help diagnose DVT
  • Venogram, to get an image of your veins and the blood clot
  • CT scan, to get more information about the blood clot
  • MRI, if more information is needed
  • Blood tests, to check your overall health or look for clotting problems in your blood

Do not eat or drink after midnight the night before your procedure.

What happens during percutaneous transcatheter treatment of DVT?

Talk with your healthcare provider about what to expect during the procedure. The details will vary depending on the type of procedure you have. They will also vary depending on what part of the body is treated. A typical procedure may go like this:

  • An IV will be put in your arm or hand before the procedure starts. You’ll receive medicines through this IV. You may be given a blood thinner, such as heparin. This is to help prevent new blood clots forming during the procedure.
  • You’ll also be given anesthesia through the IV line. It will prevent pain and make you sleep during the procedure. Or you may be given sedation. This will make you relaxed and sleepy during the procedure.
  • Hair in the area of your procedure may be removed. The area may be numbed with a local anesthesia.
  • The healthcare provider will make a small cut or puncture in a blood vessel in your groin. The provider will then insert a long, thin wire into this cut. The wire acts as a guide during the procedure.
  • The healthcare provider will then insert a thin, flexible tube (catheter) over the wire. The catheter may have other things attached to it, depending on the type of treatment. For example, it might carry clot-dissolving medicine. It may have a tiny, deflated balloon or other device attached. The tube will be threaded through the blood vessel all the way to the site of the blood clot. Continuous X-ray images may be used to show exactly where the tube is.
  • Your healthcare provider will then work to dissolve or remove the clot. A combination of treatments may be used. For example, a clot-dissolving medicine may be used along with a balloon or other device.
  • When the clot is treated, the healthcare provider will take the tube out of the blood vessel.
  • Pressure will be applied to the place where the tube entered to stop the bleeding. The site is then bandaged. Your provider may use a closure device to seal the small hole in the artery.

What happens after percutaneous transcatheter treatment of DVT?

After the procedure, you will spend several hours in a recovery room. Your healthcare team will closely watch your vital signs, such as your heart rate, blood pressure, and breathing. To help prevent bleeding, you may need to lie flat without bending your legs for several hours after the procedure. You may need to stay at the hospital for a day or more, depending on your condition. Your healthcare provider will tell you more about what to expect.

After the procedure, you may need to take medicines to help prevent blood clots. You may need to take them for a short time or take them for a longer time. The length of time depends on the cause of the blood clot. You may also need to take medicine to prevent clots before any future surgery. Your healthcare provider will let you know about any other changes in your medicines. You can take pain medicine if you need it. Ask your healthcare provider which medicines are safe to take.

Your healthcare provider will likely advise you to get back on your feet soon after the treatment. You may need to wear compression stockings. This is to help prevent the clot from forming again. It can also help prevent a new clot from forming.

You should stop smoking. It will lower your risks of blood clots forming in the future. Talk with your healthcare provider if you need help to quit smoking.

Your healthcare provider will keep track of your health after you go home. You’ll have follow-up appointments. Your healthcare provider may examine your blood vessels with an imaging test called a venogram. Make sure to keep all your follow-up appointments. It will help your healthcare provider keep track of your progress.

Call your healthcare provider right away or get medical care right away if you have any of these:

  • Swelling or pain that gets worse
  • Fluid or blood leaking from the incision site
  • Fever
  • Bleeding anywhere on your body
  • Weakness, pain, or numbness in the area
  • Symptoms of a blood clot

Follow all your healthcare provider’s instructions. This includes any advice about medicines, exercise, and wound care.

Next steps

Before you agree to the test or procedure, make sure you know:

  • The name of the test or procedure
  • The reason you are having the test or procedure
  • What results to expect and what they mean
  • The risks and benefits of the test or procedure
  • What the possible side effects or complications are
  • When and where you are to have the test or procedure
  • Who will do the test or procedure and what that person’s qualifications are
  • What would happen if you did not have the test or procedure
  • Any alternative tests or procedures to think about
  • When and how you will get the results
  • Who to call after the test or procedure if you have questions or problems
  • How much you will have to pay for the test or procedure