What are the main causes of Deep Vein Thrombosis. How is DVT diagnosed and treated. What are the potential complications of DVT. How can you prevent DVT from occurring.

Understanding Deep Vein Thrombosis: A Comprehensive Overview

Deep Vein Thrombosis (DVT) is a serious medical condition characterized by the formation of blood clots in deep veins, typically in the legs. This potentially life-threatening condition affects approximately 1 in 1,000 people in the UK annually, with the risk increasing for individuals over 40 years of age. DVT can lead to severe complications if left untreated, making early detection and proper management crucial.

What Exactly is Deep Vein Thrombosis?

DVT occurs when a blood clot forms in a deep vein, most commonly in the leg, but it can also develop in the pelvis or abdomen. These clots, also known as venous thrombosis, can cause pain, swelling, and potentially lead to more serious complications such as pulmonary embolism. Together, DVT and pulmonary embolism are referred to as venous thromboembolism (VTE).

Recognizing the Symptoms of DVT

While some cases of DVT may be asymptomatic, common signs and symptoms include:

• Pain, swelling, and tenderness in one leg (usually the calf or thigh)
• A heavy ache in the affected area
• Warm skin in the area of the clot
• Red skin, particularly at the back of the leg below the knee
• Pain that worsens when bending the foot upward towards the knee

It’s important to note that DVT typically affects one leg, although not always. If you experience these symptoms along with breathlessness or chest pain, seek immediate medical attention by calling 999 or going to A&E, as this could indicate a pulmonary embolism.

The Silent Threat: Understanding DVT Risk Factors

Several factors can increase an individual’s risk of developing DVT. By understanding these risk factors, we can take proactive steps to prevent the condition from occurring.

Who is at Risk for DVT?

While DVT can affect anyone, certain factors significantly increase the likelihood of developing this condition:

• Age: The risk of DVT increases for individuals over 40
• Personal or family history of DVT or pulmonary embolism
• Extended periods of inactivity, such as after surgery or during long journeys
• Blood vessel damage
• Certain medical conditions or treatments that increase blood clotting tendency
• Pregnancy
• Obesity or being overweight
• Use of combined contraceptive pills or hormone replacement therapy (HRT)

How Does Immobility Contribute to DVT Risk?

Prolonged immobility is a significant risk factor for DVT. When we remain inactive for extended periods, blood flow in our legs slows down, increasing the likelihood of clot formation. This is why DVT risk increases during long flights, hospital stays, or periods of bed rest. Regular movement and exercise help maintain proper blood circulation, reducing the risk of clot formation.

Diagnosing DVT: From Symptoms to Confirmation

Early diagnosis of DVT is crucial for effective treatment and prevention of complications. If you suspect you may have DVT, it’s essential to consult your GP promptly. The diagnostic process typically involves several steps.

What is the First Step in Diagnosing DVT?

The initial step in diagnosing DVT involves a thorough assessment of your symptoms and medical history by your GP. They will ask about your symptoms, risk factors, and any recent events that might have increased your risk of developing DVT.

How is the D-dimer Test Used in DVT Diagnosis?

A specialized blood test called the D-dimer test is often used in the diagnosis of DVT. This test detects fragments of blood clots in your bloodstream. A higher number of these fragments suggests a higher likelihood of having a blood clot. However, it’s important to note that the D-dimer test isn’t always conclusive, as blood clot fragments can increase after surgery, injury, or during pregnancy.

What Other Diagnostic Tools are Used for DVT?

In addition to the D-dimer test, other diagnostic tools may be employed to confirm or rule out DVT:

• Ultrasound scan: This non-invasive imaging test uses sound waves to visualize the blood flow in your veins and detect any clots.
• Venography: This involves injecting a special dye into your veins and taking X-rays to identify any blockages.
• CT or MRI scans: These advanced imaging techniques may be used in certain cases to get a more detailed view of your blood vessels.

Treatment Options for Deep Vein Thrombosis

Once DVT is diagnosed, prompt treatment is crucial to prevent complications and alleviate symptoms. The primary goals of DVT treatment are to stop the blood clot from growing, prevent it from breaking loose and traveling to the lungs, and reduce the risk of future clots.

What are the Main Treatment Options for DVT?

The main treatment options for DVT include:

1. Anticoagulant medications: These “blood thinners” help prevent further clot formation and allow the body to dissolve existing clots naturally.
2. Compression stockings: These specially designed stockings help improve blood flow in the legs and reduce swelling.
3. Thrombolysis: In severe cases, medication to dissolve the clot may be administered directly into the vein.
4. Inferior vena cava (IVC) filter: This device may be implanted to prevent clots from traveling to the lungs in patients who can’t take anticoagulants.

How Long Does DVT Treatment Typically Last?

The duration of DVT treatment varies depending on the individual case. Typically, anticoagulant therapy lasts for at least three to six months. However, some patients may need to continue treatment for longer periods or even indefinitely, especially if they have recurring DVT or certain risk factors.

Complications of Deep Vein Thrombosis: Understanding the Risks

While DVT itself is a serious condition, it can lead to potentially life-threatening complications if left untreated. Understanding these risks underscores the importance of early detection and proper management of DVT.

What is Pulmonary Embolism and How is it Related to DVT?

Pulmonary embolism (PE) is the most serious complication of DVT. It occurs when a piece of the blood clot breaks off and travels through the bloodstream to the lungs, blocking a pulmonary artery. This can be life-threatening, causing symptoms such as:

• Sudden breathlessness
• Chest pain that worsens with breathing
• Rapid heartbeat
• Sudden collapse

Approximately 1 in 10 people with untreated DVT will develop a pulmonary embolism. This highlights the critical importance of prompt DVT treatment.

Can DVT Lead to Long-term Complications?

Yes, DVT can lead to long-term complications, even after initial treatment. One such complication is post-thrombotic syndrome (PTS), which can develop in up to 50% of DVT patients. PTS symptoms include:

• Chronic leg pain
• Swelling
• Skin discoloration
• Ulcers

These symptoms can significantly impact quality of life and may persist for years after the initial DVT event.

Preventing Deep Vein Thrombosis: Proactive Measures for Risk Reduction

While not all cases of DVT can be prevented, there are several steps individuals can take to reduce their risk, especially those with known risk factors.

What Lifestyle Changes Can Help Prevent DVT?

Adopting a healthy lifestyle can significantly reduce your risk of developing DVT. Key preventive measures include:

• Maintaining a healthy weight
• Exercising regularly to improve circulation
• Avoiding prolonged periods of inactivity
• Staying hydrated, especially during long journeys
• Quitting smoking

How Can You Prevent DVT During Long Journeys?

Long periods of immobility, such as during air travel or long car rides, increase the risk of DVT. To reduce this risk:

• Take regular breaks to walk and stretch your legs
• Perform simple exercises in your seat, like ankle rotations and calf muscle contractions
• Stay hydrated by drinking plenty of water
• Wear loose, comfortable clothing
• Consider wearing compression stockings for journeys lasting more than 4 hours

Are There Medical Interventions to Prevent DVT?

For individuals at high risk of DVT, especially those undergoing surgery or hospitalization, medical interventions may be recommended:

• Anticoagulant medications: These may be prescribed prophylactically in high-risk situations.
• Compression devices: These mechanical devices improve blood flow in the legs during periods of immobility.
• Early mobilization: Encouraging movement as soon as possible after surgery can significantly reduce DVT risk.

Living with DVT: Management and Long-term Considerations

For individuals who have experienced DVT, ongoing management and lifestyle adjustments are crucial to prevent recurrence and maintain overall health.

How Does DVT Impact Daily Life?

Living with DVT or a history of DVT may require some lifestyle modifications:

• Regular medical check-ups to monitor anticoagulant therapy
• Wearing compression stockings as recommended by your healthcare provider
• Being vigilant about symptoms of recurrence or complications
• Making necessary adjustments to reduce risk factors, such as maintaining a healthy weight and staying active

Can You Exercise with DVT?

Exercise is generally beneficial for individuals with a history of DVT, as it improves circulation and overall health. However, it’s crucial to consult with your healthcare provider before starting or modifying an exercise regimen. They can provide guidance on appropriate activities and any necessary precautions.

What is the Long-term Outlook for DVT Patients?

With proper treatment and management, many individuals with DVT recover fully. However, some may experience long-term effects or have an increased risk of recurrence. Regular follow-ups with healthcare providers, adherence to prescribed treatments, and maintaining a healthy lifestyle are key to optimizing long-term outcomes.

Understanding Deep Vein Thrombosis is crucial for early detection, effective treatment, and prevention of this potentially life-threatening condition. By recognizing the symptoms, understanding the risk factors, and taking proactive measures, individuals can significantly reduce their risk of DVT and its complications. If you suspect you may have DVT or are at high risk, don’t hesitate to consult with your healthcare provider. Remember, early intervention can make a significant difference in the course of this condition.

Deep vein thrombosis (DVT) – Illnesses & conditions

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1. 1.

   About deep vein thrombosis

2. 2.

   Deep vein thrombosis causes

3. 3.

   Deep vein thrombosis treatment

4. 4.

   Complications of deep vein thrombosis

5. 5.

   Deep vein thrombosis prevention

About deep vein thrombosis

Deep vein thrombosis (DVT) is a blood clot that develops within a deep vein in the body, usually in the leg.

Blood clots that develop in a vein are also known as venous thrombosis.

DVT usually occurs in a deep leg vein, a larger vein that runs through the muscles of the calf and the thigh. It can also occur in the pelvis or abdomen.

It can cause pain and swelling in the leg and may lead to complications such as pulmonary embolism. 

DVT and pulmonary embolism together are known as venous thromboembolism (VTE).

DVT symptoms

In some cases, there may be no symptoms of DVT. If symptoms do occur they can include:

• pain, swelling and tenderness in one of your legs (usually your calf or thigh)
• a heavy ache in the affected area
• warm skin in the area of the clot
• red skin, particularly at the back of your leg below the knee

DVT usually (although not always) affects one leg. The pain may be worse when you bend your foot upward towards your knee.

Urgent advice:

Phone 999 or go to A&E if you have symptoms of DVT like:

• pain and swelling of the leg, along with either breathlessness or chest pain

Pulmonary embolism

This is a serious condition that occurs when a piece of blood clot breaks off into the bloodstream. This then blocks one of the blood vessels in the lungs, preventing blood from reaching them.

If left untreated, about 1 in 10 people with a DVT will develop a pulmonary embolism. A pulmonary embolism is a very serious condition which causes:

• breathlessness – which may come on gradually or suddenly
• chest pain – which may become worse when you breathe in
• sudden collapse 

Both DVT and pulmonary embolism need urgent investigation and treatment.

Seek immediate medical attention if you have pain, swelling and tenderness in your leg and develop breathlessness and chest pain.

Read more about the complications of DVT

DVT causes

Each year, DVT affects around 1 person in every 1,000 in the UK.

Anyone can develop DVT, but it becomes more common over the age of 40. As well as age, there are also some other risk factors, including:

• having a history of DVT or pulmonary embolism
• having a family history of blood clots
• being inactive for long periods – such as after an operation or during a long journey
• blood vessel damage – a damaged blood vessel wall can result in the formation of a blood clot
• having certain conditions or treatments that cause your blood to clot more easily than normal – such as cancer (including chemotherapy and radiotherapy treatment), heart and lung disease, thrombophilia and Hughes syndrome
• being pregnant – your blood also clots more easily during pregnancy
• being overweight or obese

The combined contraceptive pill and hormone replacement therapy (HRT) both contain the female hormone oestrogen, which causes the blood to clot more easily. If you’re taking either of these, your risk of developing DVT is slightly increased.

Read more about the causes of DVT

Diagnosing DVT

See your GP as soon as possible if you think you may have DVT – for example, if you have pain, swelling and a heavy ache in your leg. They’ll ask you about your symptoms and medical history.

D-dimer test

It can be difficult to diagnose DVT from symptoms alone. Your GP may advise that you have a specialised blood test called a D-dimer test.

This test detects pieces of blood clot that have been broken down and are loose in your bloodstream. The larger the number of fragments found, the more likely it is that you have a blood clot in your vein.

However, the D-dimer test isn’t always reliable because blood clot fragments can increase after an operation, injury or during pregnancy. Additional tests, such as an ultrasound scan, will need to be carried out to confirm DVT.

Ultrasound scan

An ultrasound scan can be used to detect clots in your veins. A special type of ultrasound called a Doppler ultrasound can also be used to find out how fast the blood is flowing through a blood vessel. This helps doctors identify when blood flow is slowed or blocked, which could be caused by a blood clot.

Venogram

A venogram may be used if the results of a D-dimer test and ultrasound scan can’t confirm a diagnosis of DVT.

During a venogram, a liquid called a contrast dye is injected into a vein in your foot. The dye travels up the leg and can be detected by X-ray, which will highlight a gap in the blood vessel where a clot is stopping the flow of blood.

DVT treatment

Treatment for DVT usually involves taking anticoagulant medicines. These reduce the blood’s ability to clot and stop existing clots getting bigger.

Heparin and warfarin are 2 types of anticoagulant often used to treat DVT. Heparin is usually prescribed first because it works immediately to prevent further clotting. After initial treatment, you may also need to take warfarin to prevent another blood clot forming.

A number of anticoagulants, known as directly acting oral anticoagulants (DOACs), may also be used to treat conditions such as DVT. These medications include rivaroxaban and apixaban, and they’ve been shown to be as effective as heparin and warfarin with less serious side effects.

You’ll also be prescribed compression stockings to wear every day, which will improve your symptoms and help prevent complications.

Read more about treating DVT

DVT prevention

If you need to go into hospital for surgery, a member of your care team will assess your risk of developing a blood clot while you’re there.

If you’re at risk of developing DVT, there are a number of things you can do to prevent a blood clot occurring, both before you go into hospital. These include temporarily stopping taking the combined contraceptive pill, and while you’re in hospital, such as wearing compression stockings.

When you leave hospital, your care team may also make some recommendations to help prevent DVT returning or complications developing. These may include:

• not smoking
• eating a healthy, balanced diet
• taking regular exercise 
• maintaining a healthy weight or losing weight if you’re obese

There’s no evidence to suggest that taking aspirin reduces your risk of developing DVT.

See your GP before embarking on long-distance travel if you’re at risk of getting a DVT, or if you’ve had a DVT in the past.

When taking a long-distance journey (6 hours or more) by plane, train or car, you should take steps to avoid getting DVT. Drink plenty of water, perform simple leg exercises and take regular, short walking breaks.

Read more about preventing DVT

Deep vein thrombosis causes

Deep vein thrombosis (DVT) sometimes occurs for no apparent reason.

However, the risk of developing DVT is increased in certain circumstances.

Inactivity 

When you’re inactive your blood tends to collect in the lower parts of your body, often in your lower legs. This is usually nothing to worry about because when you start to move, your blood flow increases and moves evenly around your body.

However, if you’re unable to move for a long period of time – such as after an operation, because of an illness or injury, or during a long journey – your blood flow can slow down considerably. A slow blood flow increases the chances of a blood clot forming.

In hospital

If you have to go into hospital for an operation or procedure, your risk of getting a blood clot increases. This is because DVT is more likely to occur when you’re unwell or inactive, or less active than usual.

As a patient, your risk of developing DVT depends on the type of treatment you’re having. You may be at increased risk of DVT if any of the following apply:

• you’re having an operation that takes longer than 90 minutes, or 60 minutes if the operation is on your leg, hip or abdomen
• you’re having an operation for an inflammatory or abdominal condition, such as appendicitis
• you’re confined to a bed, unable to walk, or spending a large part of the day in a bed or chair for at least three days

You may also be at increased risk of DVT if you’re much less active than usual because of an operation or serious injury and have other DVT risk factors, such as a family history of the condition.

When you’re admitted to hospital you’ll be assessed for your risk of developing a blood clot and, if necessary, given preventative treatment.

Blood vessel damage

If the wall of a blood vessel is damaged, it may become narrowed or blocked, which can cause a blood clot to form.

Blood vessels can be damaged by injuries such as broken bones or severe muscle damage. Sometimes, blood vessel damage that occurs during surgery can cause a blood clot, particularly in operations on the lower half of your body.

Conditions such as vasculitis (inflammation of the blood vessels), varicose veins and some forms of medication, such as chemotherapy, can also damage blood vessels.

Medical and genetic conditions

Your risk of getting DVT is increased if you have a condition that causes your blood to clot more easily than normal. These conditions include:

• cancer – cancer treatments such as chemotherapy and radiotherapy can increase this risk further
• heart disease and lung disease
• infectious conditions, such as hepatitis
• inflammatory conditions, such as rheumatoid arthritis
• thrombophilia – a genetic condition where your blood has an increased tendency to clot
• antiphospholipid syndrome – an immune system disorder that causes an increased risk of blood clots 

Pregnancy

During pregnancy, blood clots more easily. It’s the body’s way of preventing too much blood being lost during childbirth.

Venous thromboembolism (VTE) – DVT and pulmonary embolism – affects about 1 in 100,000 women of childbearing age.

DVTs are also rare in pregnancy, although pregnant women are up to 10 times more likely to develop thrombosis than non-pregnant women of the same age. A clot can form at any stage of pregnancy and up to 6 weeks after the birth.

Having thrombophilia (a condition where the blood has an increased tendency to clot), or having a parent, or brother or sister, who’s had a thrombosis, increase your risk of developing a DVT during pregnancy.

Other risk factors during pregnancy include:

• being over 35 years old
• being obese (with a BMI of 30 or more)
• expecting 2 or more babies
• having recently had a caesarean section
• being immobile for long periods of time
• smoking (find out how to stop smoking)
• having severe varicose veins
• dehydration

Low molecular weight heparin (LMWH) is usually used to treat pregnant women with DVT. LMWH is an anticoagulant, which means it prevents the blood clot getting bigger. It’s given by injection and doesn’t affect your developing baby.

Contraceptive pill and HRT

The combined contraceptive pill and hormone replacement therapy (HRT) both contain the female hormone oestrogen. Oestrogen causes the blood to clot a bit more easily than normal, so your risk of getting DVT is slightly increased. There’s no increased risk from the progestogen-only contraceptive pill.

Other causes

Your risk of getting DVT is also increased if you or a close relative have previously had DVT and:

• you’re overweight or obese
• you smoke
• you’re dehydrated
• you’re over 60 – particularly if you have a condition that restricts your mobility

Deep vein thrombosis treatment

If you have deep vein thrombosis (DVT), you’ll need to take a medicine called an anticoagulant.

Anticoagulation

Anticoagulant medicines prevent blood clots getting bigger.  They can also help stop part of the blood clot breaking off and becoming lodged in another part of your bloodstream (an embolism).

Although they’re often referred to as “blood-thinning” medicines, anticoagulants don’t actually thin the blood. They alter proteins within it, which prevents clots forming so easily.

Heparin and warfarin are 2 types of anticoagulants that are used to treat DVT. Heparin is usually prescribed first because it works immediately to prevent further clotting. After this initial treatment, you may also need to take warfarin to prevent another blood clot forming.

Heparin

Heparin is available in 2 different forms:

• standard (unfractioned) heparin
• low molecular weight heparin (LMWH)

Standard (unfractioned) heparin can be given as:

• an intravenous injection – an injection straight into one of your veins
• an intravenous infusion – where a continuous drip of heparin (via a pump) is fed through a narrow tube into a vein in your arm (this must be done in hospital)
• a subcutaneous injection – an injection under your skin

LMWH is usually given as a subcutaneous injection.

The dose of standard (unfractionated) heparin to treat a blood clot varies significantly from person to person, so the dosage must be carefully monitored and adjusted if necessary. You may need to stay in hospital for 5 to 10 days and have frequent blood tests to ensure you receive the right dose.

LMWH works differently from standard heparin. It contains small molecules, which means its effects are more reliable and you won’t have to stay in hospital and be monitored.

Both standard heparin and LMWH can cause side effects, including:

• a skin rash and other allergic reactions
• bleeding 
• weakening of the bones if taken for a long time (although rare with LMWH)

In rare cases, heparin can also cause an extreme reaction that makes existing blood clots worse and causes new clots to develop. This reaction, and weakening of your bones, is less likely to occur when taking LMWH.

In most cases, you’ll be given LMWH because it’s easier to use and causes fewer side effects.

Warfarin

Warfarin is taken as a tablet. You may need to take it after initial treatment with heparin to prevent further blood clots occurring. Your doctor may recommend that you take warfarin for 3 to 6 months. In some cases, it may need to be taken for longer, even for life.

As with standard heparin, the effects of warfarin vary from person to person. You’ll need to be closely monitored by having frequent blood tests to ensure you’re taking the right dosage.

When you first start taking warfarin, you may need to have 2 to 3 blood tests a week until your regular dose is decided. After this, you should only need to have a blood test every 4 weeks at an anticoagulant outpatient clinic.

Warfarin can be affected by your diet, any other medicines you’re taking, and by how well your liver is working.

If you’re taking warfarin you should:

• keep your diet consistent
• limit the amount of alcohol you drink (no more than 14 units of alcohol a week)
• take your dose of warfarin at the same time every day
• not start to take any other medicine without checking with your GP, pharmacist or anticoagulant specialist
• not take herbal medicines

Warfarin isn’t recommended for pregnant women who are given heparin injections for the full length of treatment.

Rivaroxaban

Rivaroxaban is a medication recommended by the National Institute for Health and Care Excellence (NICE) as a possible treatment for adults with DVT, or to help prevent recurrent DVT and pulmonary embolism.

Rivaroxaban comes in tablet form. It’s a type of anticoagulant known as a directly acting oral anticoagulant (DOAC). It prevents blood clots forming by inhibiting a substance called factor Xa and restricting the formation of thrombin (an enzyme that helps blood clot).

Treatment usually lasts 3 months and involves taking rivaroxaban twice a day for the first 21 days and then once a day until the end of the course.

Read the NICE guidance about rivaroxaban

Apixaban

NICE also recommends apixaban as a possible method of treatment and prevention for DVT and pulmonary embolism.

Like rivaroxaban, apixaban is a DOAC that’s taken orally as a tablet, and prevents blood clots forming by hindering factor Xa and restricting the formation of thrombin.

Treatment usually lasts at least 3 months and involves taking apixaban twice a day.

Read the NICE guidance about apixaban

Compression stockings

Wearing compression stockings helps prevent calf pain and swelling, and lowers the risk of ulcers developing after having DVT.

They can also help prevent post-thrombotic syndrome. This is damage to leg tissue caused by the increase in venous pressure that occurs when a vein is blocked by a clot and blood is diverted to the outer veins.

After having DVT, stockings should be worn every day for at least 2 years. This is because symptoms of post-thrombotic syndrome may develop several months or even years after having a DVT.

Compression stockings should be fitted professionally and your prescription should be reviewed every 3 to 6 months. The stockings need to be worn all day but can be taken off before going to bed or in the evening while you rest with your leg raised. A spare pair of compression stockings should also be provided.

Exercise

Your healthcare team will usually advise you to walk regularly once compression stockings have been prescribed. This can help prevent symptoms of DVT returning and may help to improve or prevent complications of DVT, such as post-thrombotic syndrome.

Raising your leg

As well as wearing compression stockings, you might be advised to raise your leg whenever you’re resting. This helps to relieve the pressure in the veins of the calf and stops blood and fluid pooling in the calf itself.

When raising your leg, make sure your foot is higher than your hip. This will help the returning blood flow from your calf. Putting a cushion underneath your leg while you’re lying down should help raise your leg above the level of your hip.

You can also slightly raise the end of your bed to ensure that your foot and calf are slightly higher than your hip.

Read more about preventing DVT

Inferior vena cava filters

Although anticoagulant medicines and compression stockings are usually the only treatments needed for DVT, inferior vena cava (IVC) filters may be used as an alternative. This is usually because anticoagulant treatment needs to be stopped, isn’t suitable, or isn’t working.

IVC filters are small mesh devices that can be placed in a vein. They trap large fragments of a blood clot and stop it travelling to the heart and lungs. They can be used to help prevent blood clots developing in the legs of people diagnosed with:

• DVT
• pulmonary embolism
• multiple severe injuries

IVCs can be placed in the vein permanently, or newer types of filters can be placed temporarily and removed after the risk of a blood clot has decreased.

The procedure to insert an IVC filter is carried out using a local anaesthetic (where you’re awake but the area is numb). A small cut is made in the skin and a catheter (thin, flexible tube) is inserted into a vein in the neck or groin area. The catheter is guided using an ultrasound scan. The IVC filter is then inserted through the catheter and into the vein.

Complications of deep vein thrombosis

The 2 main complications of deep vein thrombosis (DVT) are pulmonary embolism and post-thrombotic syndrome.

Pulmonary embolism

A pulmonary embolism is the most serious complication of DVT. It happens when a piece of blood clot (DVT) breaks off and travels through your bloodstream to your lungs, where it blocks one of the blood vessels. In severe cases this can be fatal.

If the clot is small, it might not cause any symptoms. If it’s medium-sized, it can cause chest pain and breathing difficulties. A large clot can cause the lungs to collapse, resulting in heart failure, which can be fatal.

About one in 10 people with an untreated DVT develops a severe pulmonary embolism.

Post-thrombotic syndrome

If you’ve had a DVT, you may develop long-term symptoms in your calf known as post-thrombotic syndrome. This affects around 20-40% of people with a history of DVT.

If you have DVT, the blood clot in the vein of your calf can divert the flow of blood to other veins, causing an increase in pressure. This can affect the tissues of your calf and lead to symptoms, including:

• calf pain
• swelling
• a rash 
• ulcers on the calf (in severe cases) 

When a DVT develops in your thigh vein, there’s an increased risk of post-thrombotic syndrome occurring. It’s also more likely to occur if you’re overweight or if you’ve had more than one DVT in the same leg.

Deep vein thrombosis prevention

If you’re admitted to hospital or planning to go into hospital for surgery, your risk of developing a blood clot while you’re there will be assessed.

Surgery and some medical treatments can increase your risk of developing DVT – see causes of DVT for more information.

If you’re thought to be at risk of developing DVT, your healthcare team can take a number of measures to prevent a blood clot forming.

Before going into hospital

If you’re going into hospital to have an operation, and you’re taking the combined contraceptive pill or hormone replacement therapy (HRT), you’ll be advised to temporarily stop taking your medication four weeks before your operation.

Similarly, if you’re taking medication to prevent blood clots, such as aspirin, you may be advised to stop taking it one week before your operation.

There’s less risk of getting DVT when having a local anaesthetic compared with a general anaesthetic.  Your doctor will discuss whether it’s possible for you to have a local anaesthetic.

While you’re in hospital

There are a number of things your healthcare team can do to help reduce your risk of getting DVT while you’re in hospital.

For example, they’ll make sure you have enough to drink so you don’t become dehydrated, and they’ll also encourage you to move around as soon as you’re able to.

Depending on your risk factors and individual circumstances, a number of different medications can be used to help prevent DVT. For example:

• anticoagulant medicines – such as dabigatran etexilate or fondaparinux sodium, which are often used to help prevent blood clots after certain types of surgery, including orthopaedic surgery
• low molecular weight heparin (LMWH) – often used in many cases to help prevent blood clots, including during and shortly after pregnancy
• unfractionated heparin (UFH) – often used in people with severe kidney impairment or established kidney failure 

Compression stockings or compression devices are also commonly used to help keep the blood in your legs circulating.

Compression stockings are worn around your feet, lower legs and thighs, and fit tightly to encourage your blood to flow more quickly around your body.

Compression devices are inflatable and work in the same way as compression stockings, inflating at regular intervals to squeeze your legs and encourage blood flow.

Your healthcare team will usually advise you to walk regularly after you’ve been prescribed compression stockings. Keeping mobile can help prevent the symptoms of DVT returning and may help prevent or improve complications of DVT, such as post-thrombotic syndrome.

Read more about treating DVT

When you leave hospital

You may need to continue to take anticoagulant medicine and wear compression stockings when you leave hospital.

Before you leave, your healthcare team should advise you about how to use your treatment, how long to continue using it for, and who to contact if you experience any problems.

Lifestyle changes

You can reduce your risk of getting DVT by making changes to your lifestyle, such as:

• not smoking
• eating a healthy, balanced diet
• getting regular exercise 
• maintaining a healthy weight or losing weight if you’re obese

Travelling

See your GP before long-distance travel if you’re at risk of getting a DVT, or if you’ve had a DVT in the past.

If you’re planning a long-distance plane, train or car journey (journeys of six hours or more), make sure you:

• drink plenty of water
• avoid drinking excessive amounts of alcohol because it can cause dehydration
• avoid taking sleeping pills because they can cause immobility
• perform simple leg exercises, such as regularly flexing your ankles
• take occasional short walks when possible – for example, during refuelling stopovers
• wear elastic compression stockings

Read more about preventing DVT when you travel

Travel insurance

If you’re travelling abroad, it’s very important to ensure you’re prepared should you or a family member fall ill.

Make sure you have full travel insurance to cover the cost of any healthcare you may need while abroad. This is particularly important if you have a pre-existing medical condition, such as cancer or heart disease, which may increase your risk of developing DVT.

DVT can be a very serious condition, and it’s important you receive medical assistance as soon as possible. Treating DVT promptly will help minimise the risk of complications.

Causes, Warning Signs, Treatment, and Prevention of Deep Vein Thrombosis

Written by Dean Shaban

Medically Reviewed by Poonam Sachdev on June 14, 2023

• What Is Deep Vein Thrombosis (DVT)?
• DVT Symptoms
• DVT Causes
• DVT Risk Factors
• DVT Tests and Diagnosis
• DVT Progression
• DVT Treatment
• DVT Health Disparities
• DVT Complications
• Living With DVT
• DVT Prognosis
• Can I Prevent DVT?
• Takeaways
• More

If blood moves too slowly through your veins, it can cause a clump of blood cells called a clot. When a blood clot forms in a vein deep inside your body, it causes what doctors call deep vein thrombosis (DVT). This is most likely to happen in your lower leg, thigh, or pelvis. But it can occur in other parts of your body, too.

DVT can lead to major health problems. In some cases, it can be fatal. That’s why if you think you have one, you must see a doctor right away.

Not everyone with DVT shows symptoms. But you might notice any of the following:

• Leg or arm swelling that comes on without warning
• Pain or soreness when you stand or walk
• Warmth in the area that hurts
• Enlarged veins
• Skin that looks red or blue

If a blood clot breaks free and moves through your bloodstream, it can get stuck in a blood vessel of your lung. Doctors call this a pulmonary embolism, or PE. It can be fatal.

Some people don’t know they have DVT until this happens. Signs of PE include:

• Shortness of breath
• Chest pain that’s worse when you take a deep breath
• Coughing up blood
• Higher heart rate

Learn more about DVT symptoms

The causes of DVT include things that keep blood from:

• Flowing through your leg, thigh, or pelvis
• Clotting correctly

This usually happens as a result of damage to one of your veins due to:

• Surgery
• Inflammation
• Infection
• Injury

Many things can raise your chances of getting DVT. Here are some of the most common:

• Age. DVT can happen at any age, but your risk is greater after age 40.
• Sitting for long periods. When you sit for long stretches of time, the muscles in your lower legs stay still. This makes it hard for blood to circulate, or move around, the way it should. Long flights or car rides can put you at risk.
• Bed rest. When you’re in the hospital for a long time, this can also keep your muscles still and raise your odds of DVT.
• Pregnancy. Carrying a baby puts more pressure on the veins in your legs and pelvis. What’s more, a clot can happen up to 6 weeks after you give birth.
• Obesity. People with obesity – that’s a body mass index (BMI) of 30 or higher – are at a higher risk. BMI measures how healthy your weight is based on how tall you are.
• Serious health issues. Conditions like inflammatory bowel disease, cancer, and heart disease can all raise your risk.
• Certain inherited blood disorders. Some diseases that run in families can make your blood thicker than normal or cause it to clot more than it should.
• Injury to a vein. This could result from a broken bone, surgery, or other trauma.
• Smoking . This makes blood cells stickier than they should be. It also harms the lining of your blood vessels. This makes it easier for clots to form.
• Birth control pills or hormone replacement therapy. The estrogen in these raises your blood’s ability to clot. (Progesterone-only pills don’t have the same risk.)
• Infection. When in your blood, veins, or elsewhere, it could lead to DVT.
• Inflammation. This could be due to infection, surgery, injury, or some other root cause.
• High cholesterol.

In some cases, neither the cause nor the symptoms of DVT are very clear, so tell your doctor about any changes you notice if you are at higher risk for DVT.

How many people get DVT? 

DVT symptoms can be hard to find and often go unnoticed. So it’s hard to estimate the number of diagnoses . But it’s thought that about 8 in every 10,000 people get DVT every year. And lower-leg DVT happens  in every 1 in 1,000 people. But these numbers actually could be higher.

Your doctor will first do a physical exam of your leg and lower body areas to check for symptoms. If there is any swelling, tenderness, or change in skin color, they will likely want to run some tests to see if you have DVT. Such tests include:

• Duplex ultrasound. This is the standard test for DVT. Your doctor will run an ultrasound to scan parts of your body for clots in your veins. An ultrasound scanner sends sound waves to create images showing how blood flows through your veins.  If your doctor finds a clot, they may want you to come back for more ultrasounds to see if it has grown or if there are any new ones.
• D-dimer blood test. Most people with bad DVT will have D-dimer in their blood, It’s a type of protein that comes from blood clots. Your doctor will do a blood test to see whether you have high levels of D-dimer.
• MRI. MRIs are usually done for DVT in the lower abdomen or belly area. They are not standard for the more common forms of DVT.
• Venography. This test is rarely done because it is so invasive. Your doctor will inject dye in your veins and take an X-ray to see if the dye is flowing properly through your veins. It can let your doctor to see if you have any clots. Other tests, like an ultrasound, are done first.

Find out more about DVT tests and diagnosis

DVT can progress as your symptoms get worse. Signs of acute DVT include: 

• Pain in your leg or arm. It could be swollen and feel warmer than it normally does. 
• You may notice a change in skin color. It might be red. If you have a darker skin tone, this may be harder to see. 
• A bad headache that can come on suddenly. You might also have seizures.
• Bad belly pain (if blood clots are in your abdomen)

If you are breathless or have chest pain, this can be a bad progression in your DVT. You might feel lightheaded or faint. If this happens, you need medical care right away. These could be signs of a pulmonary embolism (PE), when the clot is going into your lungs. PE can be fatal if it’s not caught early enough.

Your doctor will want to stop the blood clot from getting bigger or breaking off and heading toward your lungs. They’ll also want to cut your chances of getting another DVT.

This can be done in one of three ways:

Medications for DVT

Blood thinners are the most common medications used to treat DVT. They cut your blood’s ability to clot. You may need to take them for 6 months. If your symptoms are severe or your clot is very large, your doctor may give you a strong medicine to dissolve it. These medications, called thrombolytics, have serious side effects like sudden bleeding. That’s why they’re not prescribed very often.

Procedure for DVT

Inferior vena cava (IVC) filter. If you can’t take a blood thinner or if one doesn’t help, your doctor may insert a small, cone-shaped filter inside your inferior vena cava. That’s the largest vein in your body. The filter can catch a large clot before it reaches your lungs.

Home remedies for DVT

Compression stockings. These special socks are very tight at the ankle and get looser as they reach your knee. This pressure prevents blood from pooling in your veins. You can buy some types at the drugstore. But your doctor might prescribe a stronger version that an expert can fit for you.

Know more about the latest DVT treatments

Research shows that Black people are more likely to have DVT than White people. But they’re just as likely or less likely to have PE. 

Studies show that people with what’s known as “metabolic syndrome” are at greater risk of having a DVT event. Metabolic syndrome is a condition linked to a group of other conditions, such as obesity, high blood sugar, high cholesterol, and high blood pressure.

Black people, and especially Black women, tend to have metabolic syndrome more often than people of other racial groups. This can increase their chances of having DVT.

Up to half of people with DVT will have long-term complications because of damage to the leg vein (post-thrombotic syndrome) where blood remains too long (chronic venous insufficiency). You may notice pain, swelling, and redness, which can lead to open sores if you don’t get early treatment. In time, this can make it harder to do daily activities and even walk.

The biggest worry for a blood clot is a DVT that breaks off and causes a pulmonary embolism (see above). If the clot isn’t too big and you get the right treatment fast enough, you may recover from this, though there may be some long-term lung damage.

About a third of people who have had a DVT or PE have a higher risk of another incident.

Living with DVT can be very manageable if you stick to a good routine, eat well, and budget enough for out-of-pocket costs. It’s also important to stay aware of your mental well-being during and after a DVT.

DVT diet

While it is always good to stick to a well-balanced diet, healthy eating is especially important if you have DVT. Inflammation is known to make the risk of blood clots higher. Here are some tips for eating to lower inflammation:

• Try to include plant-based foods like fruits, veggies, nuts, and whole grains.
• Olive oil and canola oil are good subs for butter.
• If you’re going to flavor your food, try herbs and spices instead of salt.
• Red meat is fine, but try to keep it to no more than two to three times a month.
• It’s good to eat fish at least twice a week.

DVT costs

Research shows that people with DVT lose, on average, 57 short-term disability days at work and 440 long-term disability days. The out-of-pocket cost per year is about $2,500, including medical and pharmacy expenses. It may be more or less, depending on your insurance or if you are uninsured.

Managing DVT

After a DVT, you can slowly get back to your normal activities. 

• If you sit for a while, it’s good to stand up and walk for a few minutes every hour. This is especially true for road trips or long flights.
• If you’re sitting for a long time (like at work), exercise your calf muscles.
• Always wear compression socks as prescribed by your doctor. This will help with swelling.
• Try not to do anything that could cause a serious injury.
• Drink plenty of water.

DVT and mental health

The trauma of going through a blood clot can cause mental health issues for you. These may include:

• Anxiety
• Depression
• Posttraumatic stress disorder (PTSD)

If you have or think you may be having any of these or other mental health conditions as a result of your DVT, reach out to a mental health professional for one-on-one or group therapy.

Since a DVT can take up to a year to break apart, your doctor will likely want to do more ultrasounds after the first one to see if it has spread or gotten worse. 

Always take your blood thinners as prescribed and wear compression socks until your doctor tells you it’s OK to stop. You might need more blood tests to check that you have the right dosage of medications as your DVT gets better or worse.

Can DVT be cured?

Yes. With the proper treatment and attention, your blood clot can come apart over time.

Simple lifestyle changes may help lower your odds of getting one. Try these simple tips to keep your blood circulating the way it should:

• Take care of yourself. Stop smoking, lose weight, and try to be active.
• Get regular checkups. And if your doctor has prescribed a medicine to control a health problem, take it as directed.
• Don’t sit for too long. If you’re traveling for 4 hours or more, take breaks to flex and stretch your lower leg muscles. If you’re on a flight, walk up and down the aisle every hour. On long car drives, pull over every 2 hours to stretch. Wear loose-fitting clothes, and drink plenty of water.
• Plan surgery after-care. Talk to your doctor about what you can do to prevent DVT after surgery. They might suggest you wear compression stockings or take blood thinners. You’ll also want to get out of bed and start moving around.

Deep vein thrombosis can be managed  and go away if your doctor finds and treats it early enough. With a healthy diet, meds, compression socks, and enough exercise, you can live a full life during and after your DVT. Talk to your doctor right away if you think you might have DVT.

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Deep vein thrombosis: causes, symptoms

Deep vein thrombosis (DVT) occurs due to blood clotting in the deep veins of the extremities, most commonly the large veins of the legs.
Sometimes these clots are released and travel through the veins through the heart to settle in the arteries of the lungs. This related condition is known as a pulmonary embolism (PE) and can cause severe chest pain or shortness of breath. PE can be life-threatening if the embolus (circulating clot) is large.

Causes

DVT can occur when blood pools in the deep veins of your legs, when there is some factor that makes a blood clot more likely, or when there is damage to the vein wall. The blood will clot if the flow is interrupted. This may be due to compression of the vessel.
For example, when you are bedridden (after surgery) or when you sit still for long periods (such as during a long plane flight), blood can pool in the large veins in your legs and form clots. Trauma, certain types of serious illnesses, and certain medications also increase the tendency to clot.

Symptoms

About half of people with DVT have no symptoms. These are so-called “silent” DVTs that may resolve on their own or lead to a pulmonary embolism. If symptoms do occur, they usually occur in only one leg and include:

• swelling in the lower leg, ankle, foot, or (rarely) thigh;
• slight inflammation of the affected area;
• touch sensitivity;
• pain in the calf or behind the knee;
• leg cramps at night;
• the affected skin is slightly redder than usual; a bluish tint means a serious blockade;
• pain on weight bearing;
• sharp pain in lower leg when your leg is bent up;
• slightly elevated temperature;

Who is in danger?

Deep vein thrombosis occurs in about two in 1,000 people and is most common in adults over 60 years of age. Diseases and circumstances that increase the risk of developing DVT:

• obesity;
• smoking;
• pregnancy;
• use of oral contraceptives;
• cancer;
• injuries or operations on the lower extremities;
• family history of DVT;
• previous thrombosis or embolism;
• recent surgery or trauma;
• fractures of the femur or tibia;
• being bedridden or in a wheelchair;
• stroke;
• heart attack.

Diagnostics

Your doctor will review your medical history and perform a physical examination. However, more tests are needed to confirm a diagnosis of deep vein thrombosis because the symptoms are often similar to those of other conditions. Frequent diagnostic tests for DVT:

1. Doppler and vascular duplex scanning is a combination of ultrasound and a flow probe that shows the direction of blood flow in the veins. This combination will show any blockage in the veins.
2. Contrast venography involves injecting a substance into a vein that is visible on an x-ray.

Blood clots are sometimes found on a CT scan. A sample of your blood may also be sent to a laboratory to check for conditions that cause increased blood clotting.

Treatment

Treatment usually requires hospitalization and bed rest, at least initially. However, prolonged sitting in one position should be avoided. First, a combination of anticoagulant drugs is used to “thin” the blood to prevent further clotting. Regular blood tests tell your doctor when these drugs are working properly.

Your doctor will prescribe medications and monitor their effects.

Leg compression devices are often used to prevent DVT while you are in the hospital. The leg may be elevated to reduce swelling. A warm and damp bandage may be applied to the affected area to relieve pain.
In rare cases, a clot may require surgical removal.

Prophylaxis

General healthy lifestyle measures (exercise, avoiding cigarettes, and weight control) can help reduce your overall risk of developing DVT. For people who have had DVT or are at risk of developing DVT, the following preventive measures are recommended:

1. Avoid prolonged bed rest or immobility of the legs. Leg exercises help prevent ailment. Walking as soon as possible after surgery will help reduce the risk of DVT. If you are unable to exercise, your health care provider should massage your legs and perform passive exercises on them within their range of motion.
2. Ask your doctor or pharmacist about special support stockings. Make sure the stockings are snug, but not too tight in any one area, as this can block blood flow. Take them off once a day to wash them and check your skin for discoloration or irritation.
3. Keep your legs elevated when lying or sitting to help return blood to the veins in your legs.

Airline:

1. Drink plenty of (non-alcoholic) liquids while flying.
2. Raise your ankles and massage your calves regularly while you are sitting.
3. Wear loose, non-restrictive clothing.
4. Do not take sleeping pills as they will make you move less during the flight.
5. Be vigilant for symptoms of DVT for up to a month after long flights.

causes and main symptoms

Thrombosis scares everyone, and rightly so. Venous thrombosis is dangerous when a thrombus breaks off, migrates through the veins to the heart, passes through the heart and embolism – blockage of the pulmonary artery. This is a dangerous condition that can not only lead to serious complications, but also to death.

Thrombosis is the formation of a thrombus, that is, a blood clot, on the vessel wall. Such blood clots can either completely block the vein or partially.

It is deep vein thrombosis that poses the greatest danger, as it can lead to thromboembolism. While thrombosis of the veins of the upper extremities almost never leads to thromboembolism.

For the formation of a blood clot in a vein, several conditions are necessary, sometimes even one is enough. In medicine, there is a Virchow triad, which describes the main causes of blood clots in a vein.

1. Deceleration of blood flow. A good example is a long flight, when a person sits motionless for a long time with bent legs. This situation leads to stagnation of blood, which contributes to thrombosis in deep veins. That is why it is important to wear compression stockings during air travel, which will just prevent blood from stagnating and forming a blood clot.

3. Violation of the properties of blood. This includes increased blood clotting, that is, its thickening. This change in blood can be caused by dehydration, so drinking enough water is very important.

For the formation of blood clots, one or all three factors may be sufficient. For example, consider a situation where all three factors are involved. Broken leg.

Therefore, with fractures of the lower extremities, the risk of thrombosis increases significantly. However, there are situations when blood clots form for no apparent reason.

Thrombosis can be localized in different veins. Saphenous vein thrombosis is characterized by symptoms that can be diagnosed visually – this is skin redness, inflammation and induration, most often in those vessels that are prone to varicose veins. Deep vein thrombosis requires a serious diagnosis, as it can be asymptomatic. However, he poses a threat.

But still, deep vein thrombosis has three characteristic symptoms, the presence of which allows almost 90% confidence to talk about the fact of thrombosis.

The main symptom of deep vein thrombosis is swelling. They can be expressed to varying degrees, depending on which vein the thrombus is in – in a large or in a small one. Most often, edema in thrombosis is asymmetric – it rarely occurs on two legs at once. Usually it is localized only on one limb. If your legs have been swollen for 3 years, then it is unlikely that a fresh blood clot can be suspected during the diagnosis. With thrombosis, swelling is usually sudden and acute, accompanied by pain.

Why does swelling of the leg appear with thrombosis? This is due to the fact that fluid seeps through the wall of the vein. The fluid should move towards the heart, but because of the thrombus it cannot rise, therefore it looks for a way out through the vessels, getting into the subcutaneous fat and, accordingly, giving edema.

As a rule, edema is localized in the lower third of the lower leg, but if blood clots form at the level of the femoral vein, the entire leg will swell.

The second sign of a deep vein thrombus is pain. Most often, pain occurs in the lower leg and in the popliteal region, depending on which vein is thrombosed. Pain in the thigh area almost never bothers patients, even though a blood clot can also be in the femoral vein.

Pain, like swelling, is sudden and sharp. It can be described as bursting or pulling. It occurs for no apparent reason, that is, not due to injury or sprain. Sometimes a person may even limp while walking, as the pain of a blood clot increases during movement.

The change in skin tone is due to the fact that the blood in the vein cannot flow into the heart area, as it should, but seeps through the walls of the vessel, enters the subcutaneous fat, causing edema, and the edema already provokes a change in skin color.

For the diagnosis of thrombosis, there are additional symptoms that are named after those specialists who discovered these symptoms.

This symptom was first described by the American surgeon Homans, after whom it is named.

The patient needs to take a sitting or lying position and stretch the legs. Then, with an effort, pull the feet towards you. With such a movement, in the presence of a blood clot, pain occurs on the back surface of the lower leg of the affected leg.

To determine the presence of a blood clot, you will need a cuff from a tonometer. It must be worn on the lower third of the leg or above. When creating pressure from 60 to 150 mm Hg. Art. in the presence of thrombosis, palpable pain appears.