Deep Vein Thrombosis (DVT): Causes, Symptoms, and Treatment

Deep Vein Thrombosis (DVT) is a condition where a blood clot forms in a deep vein in your legs. These clots usually occur after prolonged immobility and can cause symptoms such as swelling, pain, and redness in your leg. Although DVT is a serious condition, with early diagnosis and proper treatment, you can prevent life-threatening complications and achieve complete recovery.

What is Deep Vein Thrombosis?

In Deep Vein Thrombosis, a clot forms in the larger vessels located between the muscles of your legs. This clot blocks the flow of blood toward the heart. The basic mechanism of DVT is explained by slowing of blood flow (stasis), damage to the vessel wall, and increased tendency of blood to clot (known as “Virchow’s Triad”).

The clot can adhere to the vessel, or in more serious cases, it can break away from the vessel and reach the lungs through blood circulation. This clot fragment that settles in the lung vessels is called pulmonary embolism and this condition is life-threatening. DVT usually develops in the vessels of the calf or thigh region.

What Causes Deep Vein Thrombosis?

Deep Vein Thrombosis usually occurs in situations such as slowing of blood flow, damage to the vessel wall, or increased tendency of blood to clot. Prolonged immobility (long airplane or bus trips, bed rest), major surgeries, some chronic diseases, and genetic predisposition are the main factors that increase DVT risk. Pregnancy, birth control pill use, and cancer are also among the risk factors.

The main causes and risk factors leading to DVT formation are:

Prolonged Immobility:

• Long Travels: Legs remaining bent and immobile for long periods during long airplane, bus, or car trips.
• Bed Rest: Long-term bed dependency after illness, surgery, or accident.
• Stroke: Movement restriction on one side of the body.
• Surgeries: Especially major orthopedic surgeries (hip or knee replacement), abdominal or chest surgeries are risky due to vessel damage and immobility.
• Vessel Damage: Damage to the vessel wall after trauma (accident, fall) or surgical intervention can trigger clot formation.
• Cancer and Cancer Treatment: Cancer cells can increase the blood’s tendency to clot. Chemotherapy can also increase DVT risk.
• Clotting Disorders (Thrombophilia): Some genetic or hereditary blood disorders, congenital or acquired, can cause blood to clot more easily than normal.
• Pregnancy and Postpartum Period: During pregnancy, the pressure of the uterus on vessels and hormonal changes, and in the postpartum period, increased clotting tendency increases risk.
• Birth Control Pills and Hormone Therapy: Medications containing estrogen can increase the blood’s tendency to clot.
• Obesity: Excess weight increases pressure on vessels and slows blood flow.
• Heart Failure: The heart’s inability to pump blood adequately can cause blood pooling in the legs.
• Age: DVT risk increases as age advances.
• Smoking: Smoking damages vessel walls and increases the blood’s tendency to clot.

What are the Symptoms of Deep Vein Thrombosis?

The symptoms of Deep Vein Thrombosis usually appear in one leg and can have sudden onset. Swelling, pain, and tenderness in your leg are the most common symptoms. Pain is usually described as cramping or stretching and may worsen with walking or moving the leg. You may also see increased warmth, redness, or bluish color change in the skin of your leg. However, sometimes DVT can progress without any symptoms.

The most common symptoms of DVT are:

• Swelling in One Leg: You usually notice sudden-onset swelling in the affected leg. This swelling may be noticeable when compared to your other leg.
• Leg Pain: Pain is usually felt in the calf or thigh region as cramping, stretching, or throbbing. The pain may especially worsen with walking or standing up and may ease with rest.
• Tenderness or Pain with Touch: You may feel tenderness or pain when you touch your affected leg.
• Increased Warmth in the Leg: The leg with DVT may feel warmer than your other leg.
• Redness or Color Change: You may see redness or sometimes bluish-purple color change in the skin of the affected leg.
• Prominence of Vessels: The vessels under the skin may appear more prominent and dilated.

Pulmonary Embolism Symptoms (Emergency Situation):

If the clot in your leg breaks off and goes to your lungs, you may experience one or more of the following symptoms. This situation requires emergency medical intervention:

• Sudden onset shortness of breath
• Chest pain (usually increases with deep breathing)
• Cough (sometimes bloody sputum may accompany)
• Rapid heartbeat
• Dizziness or fainting

Remember, DVT can sometimes progress with mild symptoms or may not cause any symptoms. Therefore, if you have risk factors, it is important to be careful.

Who Gets Deep Vein Thrombosis?

Deep Vein Thrombosis is more common especially in individuals who experience prolonged immobility (long trips, post-surgical bed rest), those who have recently undergone major surgery, or those receiving cancer treatment. Pregnancy, birth control pill use, and genetic disorders that increase the blood’s tendency to clot also increase DVT risk. Elderly and obese individuals are also at risk.

How is Deep Vein Thrombosis Diagnosed?

Deep Vein Thrombosis diagnosis begins with your doctor’s careful physical examination and evaluation of your symptoms. Doppler Ultrasonography test is usually used to confirm the diagnosis. This painless test images the blood flow in the vessels in your legs and possible clots. In rarer cases, additional tests such as D-Dimer blood test or venography may also be used.

When you consult your doctor with suspected DVT, the following steps are followed for diagnosis:

• Physical Examination and Medical History: Your doctor checks the swelling, tenderness, and color changes in your leg. Detailed information is obtained about your past illnesses, surgeries, medications you use, and family history. Particularly, conditions such as recent immobility or long trips are questioned.
• D-Dimer Blood Test: This test shows the presence of clot breakdown products in the blood. A normal D-Dimer test result largely rules out the possibility of DVT. However, a high D-Dimer result alone is not sufficient to diagnose DVT, as other conditions can also elevate this level. This test is usually used in patients thought to have low or moderate risk of DVT.
• Doppler Ultrasonography (Venous Ultrasound): This is the most commonly used and most reliable test in DVT diagnosis. It creates images of the veins in your legs and the blood flow within them using sound waves. It clearly shows the presence, location, and size of the clot. It is a painless test that does not contain radiation.
• Venography: This is an invasive test that is rarely used. X-ray images are taken by injecting a special contrast agent into the vessels. It shows blockages in blood flow. It is usually preferred in complex cases where ultrasound does not provide sufficient information or where definitive diagnosis is needed.

Your doctor will determine the appropriate diagnostic methods for you by evaluating your symptoms and risk factors. Early diagnosis is very important to prevent serious complications that DVT can cause.

How is Deep Vein Thrombosis Treated?

The main goal in Deep Vein Thrombosis treatment is to prevent the clot from growing, prevent the formation of new clots, and prevent serious complications such as pulmonary embolism. The foundation of treatment consists of blood-thinning medications (anticoagulants). These medications do not help dissolve the clot but support your body’s natural mechanisms to dissolve the clot. Additionally, compression stockings and in some cases interventional methods can also be used.

The main methods used in DVT treatment are:

Blood-Thinning Medications (Anticoagulants):

• These medications reduce the blood’s ability to clot, preventing the clot from growing and preventing the formation of new clots. They help the existing clot dissolve over time through the body’s own mechanisms.
• Treatment usually lasts at least 3-6 months but may last longer depending on your risk factors.
• Treatment usually begins with injections (low molecular weight heparin), then transitions to oral medications (Warfarin or new generation oral anticoagulants – DOACs).
• While using blood thinners, it is very important to maintain regular follow-up and communication with your doctor regarding possible side effects (bleeding).

Compression Stockings (Pressure Stockings):

• These stockings apply external pressure to your legs, preventing blood from pooling in leg vessels and improving blood flow.
• They help reduce the risk of “post-thrombotic syndrome,” a long-term complication that can occur after DVT. It is important to regularly wear stockings at the pressure and size recommended by your doctor.

Thrombolytic Therapy (Clot-Dissolving Medications):

• In more serious or extensive DVT cases, especially if the risk of pulmonary embolism is high or there is significant loss of function in the leg, medications that directly dissolve the clot can be used.
• These medications are given intravenously or directly into the clot through a catheter. They require close monitoring in the hospital due to high bleeding risk.

Vena Cava Filter:

• In very special cases where blood-thinning medications cannot be used or the risk of the clot going to the lungs continues despite medication, a temporary or permanent filter can be placed in the vena cava, the main vein.
• This filter is designed to prevent clots coming from the legs from reaching the lungs.

Your treatment plan will be determined individually by your doctor, taking into account the severity of DVT, your general health condition, and risk factors.

What are the Risks of Deep Vein Thrombosis?

Deep Vein Thrombosis is a serious health problem in itself, but its biggest risk is developing pulmonary embolism (lung embolism). This means the clot in your leg breaks off and goes to the lungs, creating a life-threatening situation. Additionally, some people who have had DVT may develop post-thrombotic syndrome, which progresses with long-term swelling, pain, and skin changes in the leg. Recurrent DVT attacks are also an important risk.

The potential risks and complications that DVT can cause are:

Pulmonary Embolism (Lung Embolism):

• This is the most serious and potentially fatal complication of DVT.
• It occurs when a piece of the clot in your leg breaks off and travels through blood circulation to the lungs, blocking the vessels there.
• It manifests with symptoms such as sudden shortness of breath, chest pain, rapid heartbeat, and cough. It requires emergency medical intervention.

Post-Thrombotic Syndrome (PTS):

• This is a chronic condition that can develop in approximately half of people who have had DVT.
• Due to the damage the clot causes to the vessel, the valves inside the vessel may not function properly. This leads to chronic swelling, pain, feeling of heaviness, cramps, itching, skin color changes in the leg, and in some cases skin ulcers (wounds).
• Compression stockings and regular exercise are important in preventing this syndrome or reducing its severity.

Recurrent DVT:

• A person who has had DVT has a high risk of having DVT again in the future. This risk depends on underlying causes and adherence to treatment.

Chronic Venous Insufficiency:

• This is the permanent damage to the valves in the vessels, resulting in blood pooling in the legs and causing chronic problems.

To minimize these risks, it is very important that you strictly follow the treatment recommended by your doctor, use your medications regularly, and maintain your lifestyle changes.

Deep Vein Thrombosis and Lifestyle

Although receiving a Deep Vein Thrombosis diagnosis requires some important adjustments in your life, it does not prevent you from living an active and healthy life. Regularly using your blood-thinning medications, wearing your compression stockings, and staying physically active ensures that the disease is kept under control. Avoiding prolonged immobility and adopting healthy habits both reduces DVT risk and improves your overall quality of life.

When Should You See a Doctor?

If you notice sudden-onset swelling, pain, redness, increased warmth, or tenderness in your legs, you should see a doctor without delay. Especially if symptoms such as shortness of breath, chest pain, or cough accompany, this may be a sign of pulmonary embolism and you need to get emergency medical help. If you have DVT risk factors, you should talk to your doctor about preventive measures and possible symptoms.

It is very important to see a doctor immediately in the following situations:

Sudden-Onset Symptoms in Your Leg:

• Noticeable swelling in one leg
• Persistent leg pain in the form of cramping, stretching, or throbbing
• Increased warmth or redness in your leg
• Tenderness or pain with touch in your leg
• Bluish or purplish color change in skin

Pulmonary Embolism Symptoms (Emergency!):

If these symptoms appear, immediately call 112 Emergency Help line or go to the nearest emergency room for medical help:

• Sudden onset and unexplained shortness of breath
• Chest pain (especially increasing with deep breathing or coughing)
• Sudden onset cough (sometimes bloody sputum may accompany)
• Sudden increase in heart rate (tachycardia)
• Dizziness or fainting

Remember, DVT is a serious condition but can be successfully managed with early diagnosis and treatment. Do not ignore the symptoms and definitely consult a healthcare professional if in doubt.

References: Deep Vein Thrombosis