Venous Thrombosis: What is it? Causes, Symptoms, Diagnosis and Treatment

It refers to the formation of a blood clot in a blood vessel.

While clots can form in an artery or vein, the clots that occur in the veins are called venous thrombosis.

The clot, or “thrombus,” blocks or impairs blood flow in the vein, leading to symptoms and secondary complications.

Thrombosis can occur for no apparent reason, but is often associated with a hereditary predisposition to blood clots, surgical procedures, immobility, use of oral contraceptives, or underlying medical conditions.

It is known that medical conditions such as pregnancy, cancer, inflammatory bowel disease, certain rheumatological disorders and obesity increase the risk of thrombosis.

Thrombosis often occurs in the legs.

When it affects the deep veins, which are those that you can not see under the skin, it is called deep vein thrombosis.

Embolism refers to the sudden blockage of a blood vessel from a clot or other material.

Unlike a thrombus that develops at the site of blockage, an embolus originates in one place in the body and travels to a second site where it causes blockage.

One of the most common types of embolism occurs in the lung, called pulmonary embolism .

Pulmonary embolisms usually result from a deep vein thrombosis that formed in the leg or pelvis region, and can be life-threatening.


Venous thrombosis is a serious disorder with a high incidence, this incidence varies between different ethnic groups, but underdiagnosis continues to play a very important role.

The causes of thrombosis are both genetic and acquired.

The most important risk factors are cancer and certain types of surgery.

The risk factors for intermediate resistance are lifestyle factors, such as the use of hormones and overweight, genetic factors, as well as the deficiencies of natural anticoagulants.

Many other genetic risk factors that are common have been identified, but they only have a weak effect on thrombosis.

Future objectives to reach specific prevention and treatment will derive from the integration of the large number of risk factors into individual risk prediction tools.


A venous thrombosis can form anywhere in the body and the symptoms depend on where the clot is.

Signs and symptoms include pain or stiffness, swelling and redness in the affected leg.

Discomfort can start from the upper part of the thigh to the ankle.

All of these signs and symptoms do not need to be present if you have a blood clot in your leg.

Frequently, patients only experience swelling and some discomfort.

If the clot or part of the clot travels to the lungs, a pulmonary embolism, then you may experience chest pain, shortness of breath or lightheadedness.

Some patients receive medications or fluids through catheters placed in the veins.

Catheters can stimulate thrombus formation in the vein near and around the catheter, called deep vein thrombosis associated with the catheter.

Because catheters are usually located in an arm or thorax, this thrombus can cause inflammation of the arm or neck, with or without the presence of pain.


An ultrasound test is the most commonly used test to diagnose a blood clot in the leg or arm.

A CT scan and x-ray are commonly used to diagnose a pulmonary embolism.

A computerized axial tomography is used to diagnose thrombosis in the abdomen, pelvis, and head.

Occasionally, a thrombosis is discovered in the thorax, abdomen or pelvis during a CT scan performed for another reason.

The doctor must develop individualized treatment plans for these clots discovered incidentally.

In addition to finding the clot itself, the diagnostic evaluation sometimes involves blood tests that can help explain why the clot occurred in the first place.

Some of these tests look for specific genetic changes, others look for antibodies in their blood and others evaluate the amount or activity of the proteins that help to form and eliminate blood clots.


Anticoagulation is the cornerstone for treating deep vein thrombosis and pulmonary embolism.

Anticoagulant medications reduce the body’s ability to form blood clots.

The blood vessels suffer from small impairments as part of their functions, and the coagulation system acts to prevent bleeding.

The coagulation system is also responsible for stopping bleeding when a wound occurs.

The goal of anticoagulant therapy is to find the middle term where coagulation takes place when the body needs it, and at the same time prevent thrombosis or embolism from occurring.

That is, anticoagulant therapy seeks to prevent new clots and the growth of current clots, while the body’s natural system of blood clots, called “lysis” or “lytic” system, eliminates thrombus or embolism.