Deep Vein Thrombosis

Deep Vein Thrombosis (DVT) is a condition where a blood clot forms in one of the
deep veins of the body, typically in the legs. DVT can be dangerous because the clot
can break loose, travel to the lungs, and cause a pulmonary embolism (PE), a life-
threatening condition.

🔹 Causes and Risk Factors

DVT occurs when blood flow in the veins is sluggish, hypercoagulable or thicker and some damage to the inner lining of blood vessel wall. It is often related to one or more of the following risk factors:

1. Immobility: Prolonged periods of sitting or bed rest (e.g., long flights, hospitalization, or after surgery) can slow blood flow, increasing the risk of clot formation.
2. Surgery: Major surgeries, especially involving the legs, hips, or abdomen, can increase the risk of DVT. The body’s response to injury and immobility after surgery can lead to clotting.
3. Trauma or injury to a vein: A broken leg or other injury can damage veins, increasing the likelihood of clot formation.
4. Pregnancy: Pregnancy increases pressure on the veins in the pelvis and legs, raising the risk of DVT, especially in the later stages.
5. Hormone therapy: Birth control pills or hormone replacement therapy can increase clotting risk.
6. Obesity: Extra body weight puts more pressure on the veins, particularly in the legs.
7. Cancer: Certain cancers and cancer treatments (chemotherapy) increase the risk of DVT.
8. Smoking: Smoking damages blood vessels, increases clotting, and contributes to other risk factors like obesity and poor circulation.
9. Older age: The risk of DVT increases with age, particularly over 60.
10. Family history of DVT or blood clotting disorders: Inherited conditions, such as factor V Leiden or antithrombin III deficiency, can increase the risk of clotting.
11. Predisposing mechanical obstruction or compression syndrome: For example, a severe form of May Thurner syndrome in an individual with any of the above factors can result in an extensive DVT from the abdomen [involving the iliac veins] to the calf.

🔸 Symptoms of DVT

DVT can sometimes develop without obvious symptoms, but when symptoms do occur, they may include:

1. Swelling: Typically in one leg, often accompanied by a feeling of heaviness or tightness.
2. Pain or tenderness: Usually felt in the leg or calf, and may get worse when standing or walking.
3. Red or discolored skin: The skin over the affected vein may appear reddish or have a bluish tint.
4. Warmth: The area around the clot may feel warm to the touch.
5. Swollen veins: In severe cases, veins near the surface of the skin may become more visible and engorged.
6. Phelgmasia Cerulea Dolens: Often seen with an extensive blood clot involving the iliac veins in the abdomen to the calf. This results in significant swelling, pain and tenderness. The severely increased pressure in the legs can start to compromise arterial blood flow.

It's important to note that DVT can sometimes occur without noticeable symptoms, which is why it's often referred to as a "silent" condition.

🔹 Diagnosis of DVT

To diagnose DVT, doctors may use a combination of physical exams and imaging tests:

1. Physical Exam: The doctor will assess your symptoms, check for swelling or tenderness, and listen to your medical history.
2. Ultrasound: The most common test to diagnose DVT. It uses sound waves to create an image of the veins and identify the presence of a clot.
3. D-dimer test: A blood test that measures the presence of D-dimer, a substance released when a blood clot breaks down. Elevated D-dimer levels suggest the presence of a clot, but other conditions can also cause elevated D-dimer levels.
4. CT or MRI scan: In certain cases, if ultrasound results are inconclusive or if the clot is in a location difficult to assess (such as in the pelvis), a CT scan or MRI may be used.

🔸 Treatment of DVT

Treatment for DVT aims to prevent the clot from getting larger, reduce the risk of the clot breaking loose, and prevent complications like pulmonary embolism.

1. Medications

• Anticoagulants (blood thinners): The most common treatment for DVT. These medications do not dissolve the clot but prevent it from growing and reduce the risk of new clots forming. Common blood thinners include:
• Heparin: Usually given in a hospital setting via injection or IV.
• Low-molecular-weight heparins (e.g., enoxaparin): Injected under the skin, often used for home treatment.
• Warfarin (Coumadin): An oral medication that takes several days to become effective, requiring careful monitoring of blood levels.
• Direct oral anticoagulants (DOACs): Newer blood thinners (e.g., apixaban, rivaroxaban) that do not require routine blood testing and have fewer dietary restrictions.
• Thrombolytics (clot-busting drugs): In severe cases, these drugs may be used to dissolve the clot quickly, though they come with a higher risk of bleeding.
• Compression stockings: Wearing these can help reduce swelling, alleviate pain, and prevent complications like post-thrombotic syndrome (chronic pain and swelling after DVT).

2. Inferior Vena Cava (IVC) Filter

If anticoagulants are not effective or cannot be used (due to bleeding risks), an IVC filter may be placed in the large vein (inferior vena cava) to trap blood clots before they can reach the lungs and cause a pulmonary embolism.

3. Endovascular intervention:

In selected cases such as Phelgmasia Cerluea Dolens or extensive DVT involving the iliac veins in the abdomen, endovascular intervention with thrombectomy [actual removal of clot with special devices] and catheter directed thrombolysis can be considered. With this procedure we perform an intravascular ultrasound of the iliac veins to assess the cause of the extensive DVT. If appropriate the blockage or compression of the main iliac vein can be treated with a stent with good clinical results.

🔹 Complications of DVT

• Pulmonary Embolism (PE): The most serious complication. If part of the clot breaks loose and travels to the lungs, it can block the pulmonary artery, causing shortness of breath, chest pain, and even death. Clots occurring in the iliac veins and those above the calf are at higher risk for breaking loose and causing a PE.
• Post-thrombotic Syndrome (PTS): A long-term complication that occurs in some people after DVT. It includes chronic pain, swelling, and discomfort in the affected leg. This condition is seen more commonly in patients with Phelgmasia Cerluea Dolens or extensive DVT involving the iliac veins in the abdomen. This long term complication can be reduced with endovascular intervention.
• Chronic Venous Insufficiency (CVI): Damaged veins from DVT can lead to poor circulation in the leg, causing swelling, varicose veins, and skin changes.

🔸 Prevention of DVT

Preventing DVT, especially during periods of immobility, is crucial:

1. Movement and exercise: Walking or leg exercises help promote circulation and reduce the risk of blood clot formation.
2. Compression stockings: Especially useful for people who are at higher risk (e.g., post-surgery or pregnant).
3. Hydration: Staying well-hydrated helps keep blood from becoming too thick, reducing clot risk.
4. Medications: For people at high risk, such as those undergoing surgery or prolonged immobilization, anticoagulants or low-dose aspirin may be prescribed to prevent DVT.
5. Avoid prolonged immobility: For long trips or after surgery, take breaks to move around or perform leg exercises to maintain circulation.

🔹 Prognosis

With appropriate treatment, many people with DVT can recover without complications. However, pulmonary embolism is a significant concern, and if left untreated, it can be fatal. Post-thrombotic syndrome can also lead to long-term discomfort, but it can be managed with lifestyle adjustments and medications.