What is a Thrombotic Stroke?

Illustration of the cause of a transient ischemic attack
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A thrombotic (throm-BOT-ik) stroke, a type of ischemic stroke, occurs when a blood clot, or thrombus, forms in an artery supplying blood to the brain. The blood clot blocks the flow of oxygen-rich blood to a portion of the brain.

Also known as a cerebral thrombosis, or a cerebral infarction, a thrombotic stroke is responsible for more than half of all strokes. A thrombotic stroke is further divided into two categories that correlate to the area of the blockage within the brain – large-vessel thrombosis and small-vessel thrombosis.

A thrombotic stroke may be preceded by a series of one or more transient ischemic attacks, also known as “mini-strokes” or TIAs. A TIA may last a few minutes or up to a day and are often a sign of an impending stroke. The symptoms of a TIA are similar to those of a stroke.

Causes of a Thrombotic Stroke

A thrombotic stroke is most commonly caused by the narrowing of the arteries in the head or neck. Most often caused by atherosclerosis, the arteries become narrowed resulting in the collection of blood cells and the formation of blood clots. Other causes of a thrombotic stroke include the use of recreational drugs, trauma to the blood vessels of the neck and blood clotting disorders.

Risk Factors for a Thrombotic Stroke

An ischemic stroke is the most common type of stroke. People with high cholesterol levels and atherosclerosis are at high risk for developing a thrombotic stroke. Other conditions that place people at a higher risk for stroke include a previous stroke or “mini-stroke”, high blood pressure (hypertension), heart disease, smoking, or diabetes.

Types of Thrombotic Stroke

There are two types of blood clots that cause a thrombotic stroke. They include large vessel thrombosis and small vessel disease.               

Large Vessel Thrombosis

Large vessel thrombosis is the most common cause of thrombotic stroke and occurs in the larger blood-supplying arteries of the brain, such as the carotid or middle cerebral.

Most cases of large vessel thrombosis are caused by long-term atherosclerosis combined along with the rapid formation of blood clots. Patients with high cholesterol are at high risk for this type of stroke.

Small Vessel Thrombosis

This type of thrombotic stroke occurs when blood flow is blocked to a smaller, yet deeper penetrating arterial vessel. This type of stroke, also known as a lacunar stroke, most often occurs in patients with high blood pressure.

Symptoms of a Thrombotic Stroke

A person who is having a stroke may not notice they are experiencing symptoms. A simple test for people who notice signs or symptoms of a stroke is to ask the person to think “FAST” do the following:

  • Face –Ask the person to smile.
    Does one side of their face droop?
  • Arms –Ask the person to raise both arms.
    Does one of the arms drift downward or are they unable to raise either one of their arms?
  • Speech – Ask the person to repeat a simple phrase.
    Is their speech slurred?
  • Time –Seek immediate medical attention if you observe any of these signs.

    Don’t wait for the symptoms to disappear. The sooner a stroke is treated, the less the complications –brain damage and disability result.

    Symptoms of a thrombotic stroke include:

    • Trouble understanding or speaking
    • Numbness of the arm, face or leg
    • Blurred or blackened vision in one or both eyes
    • Double vision
    • Sudden, severe headache
    • Vomiting
    • Dizziness
    • Difficulty walking
    • Loss of balance or coordination

    Reducing Risk Factors for a Thrombotic Stroke

    While certain risk factors as age, gender, heredity and ethnicity are uncontrollable, a patient with risk factors for a stroke can reduce their risk of stroke by beginning treatment that controls their risk factors and adjusts their lifestyle choices.

    Ways to control risk factors for a stroke include:

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