A brain embolism is a blockage in an artery within the brain or in an artery that supplies blood to the brain. Blockages can be caused by a blood clot, fat globule, or air pocket within an artery.

A brain embolism causes an embolic stroke. Without prompt treatment, an embolic stroke can lead to brain damage, disability, and even death.

This article describes what a brain embolism is, including its symptoms, causes, and prevention. We also outline how to recognize the signs of a stroke, and what to expect in terms of treatment, recovery, and outlook.

An MRI showing a brain embolism, a blockage in an artery within the brain or in an artery that supplies blood to the brain.Share on Pinterest
mr.suphachai praserdumrongchai/Getty Images

Stroke affects around 795,000 people in the United States each year. In the U.S., stroke is the #5 cause of death, and the leading cause of disability.

When a stroke happens, it is vital that a person receives medical treatment quickly to limit damage to the brain. The FAST acronym is a useful way to spot the signs of stroke:

F – Face: Ask the person to smile. Has their mouth or eye drooped on one side?

A – Arms: Ask the person to raise both arms. Does one arm drift downwards?

S – Speech: Is the person’s speech slurred or unclear? Can they understand what others are saying?

T – Time: It is time to call 911 if a person shows any of the above signs.

A person should note the time when stroke symptoms first appear, as this can help medical professionals decide the best treatment. The most effective treatment for stroke is a thrombolytic drug known as a tissue plasminogen activator (tPA), which helps break up blood clots. However, this drug is most effective if a person receives it within 3 hours of symptom onset.

A brain embolism happens when an artery that carries oxygen-rich blood and nutrients to the brain becomes blocked.

Blockages can occur when a blood clot from elsewhere in the body travels through the bloodstream and lodges in an artery inside the brain, or one that feeds into the brain. Once an artery is blocked, brain cells do not receive the oxygen they need to function. This causes the brain cells to start dying within minutes.

A brain embolism is one type of ischemic stroke, in which blood flow to the brain is blocked. Ischemic strokes make up 87% of all strokes.

A transient ischemic attack (TIA) or “mini stroke,” is caused by a temporary clot that usually lasts no longer than 5 minutes. A TIA can be a warning sign of a future stroke.

Symptoms of a stroke are similar for men and women but can vary depending on where in the brain the blockage occurs.

The most common symptoms of a stroke are:

  • drooping on one side of the face
  • arm weakness or numbness
  • difficulty speaking or understanding speech

Other possible symptoms include:

Some potential causes of brain embolism are:

Blood clots

Blood clots can form anywhere in the body. Once formed, a blood clot or a fragment of the blood clot can travel through the bloodstream and lodge in one or more arteries of the brain.

Embolisms are more common in people who have the heart condition atrial fibrillation (AF), which causes the heart to beat at a fast and irregular pace. In AF, a blood clot can form in the heart and a piece of the clot can break off and travel to the brain.


A fat embolism is a piece of fat that gets lodged within a blood vessel, blocking blood flow.

Fat embolisms sometimes occur after a person fractures a long bone, such as a thigh bone. Fat from the bone marrow can leak out and enter the bloodstream. This can also happen following bone surgery or after sustaining severe burns.


Embolisms can occur as a result of air bubbles or other gases entering the bloodstream. According to one 2013 journal article, this can be a complication of:

  • having a catheter inserted
  • sustaining a blunt or penetrating injury
  • scuba diving, where divers rise to the surface too quickly
  • childbirth


Cholesterol can build up in the arteries, causing them to narrow. Fragments of cholesterol can break away and travel through the bloodstream. Fragments that are too large to pass through an artery will cause an embolism.

Amniotic fluid

In rare cases, amniotic fluid and other fetal material can leak into the mother’s bloodstream during labor, causing a blockage.

The risk of stroke increases with age for both males and females. However, stroke is more common among women than among men. Women are also more likely to die of stroke compared to men.

Race is another risk factor for stroke. African American people are at greater risk of stroke compared to Caucasian people. This increased risk is linked to the prevalence of the following conditions among African Americans:

Certain medical and lifestyle factors can also increase a person’s risk of having a brain embolism.

Medical risk factors

Medical risk factors for stroke include:

Having a family history of stroke also increases the likelihood that a person will experience stroke themselves.

Lifestyle risk factors

Lifestyle risk factors for stroke include:

  • eating an unhealthy diet
  • lack of physical activity
  • obesity
  • drinking too much alcohol
  • smoking

The first steps toward diagnosing a brain embolism include:

  • checking the pulse for an irregular heartbeat
  • measuring blood pressure
  • testing the blood for clotting factors that signal the formation of a blood clot

A person will then need a brain scan to help determine the location, cause, and severity of the embolism. A doctor will order one of the following scans:

The treatment for a brain embolism may include medication, surgery, or both. The type of treatment a person receives depends on several factors, including:

  • the length of time since symptoms first appeared
  • the location of the embolism
  • the cause of the embolism


A doctor may prescribe one or more of the following medications to treat a brain embolism:

  • thrombolytic medication to dissolves blood clots. A person must receive these within 3 hours of symptom onset.
  • aspirin or similar antiplatelet medications, which reduce the chance of further clots forming
  • anticoagulants, which change the blood chemistry to prevent clots from forming
  • blood pressure medications to stabilize blood pressure
  • statins to reduce blood cholesterol


In some cases, a surgeon may perform a procedure called a “mechanical thrombectomy.” This involves inserting a catheter into an artery, often in the groin. The surgeon then inserts a small clot-removing device through the catheter to pull or suck out the clot.

Mechanical thrombectomy is only suitable for around 1 in 10 people who experience stroke. For the procedure to be successful, a person must receive the treatment within 6 hours of symptom onset.

Brain embolisms can affect people in different ways depending on their severity and their location within the brain.

After a stroke, a person will likely need time to rebuild their physical strength and to regain control over any functions they have lost.

Most people who have experienced a stroke will continue taking medication as they recover. Their medical team will monitor them regularly and adjust their medications as necessary.

A person who is recovering from a stroke may also benefit from the following services, depending on the nature and severity of their stroke:

  • physiotherapy: A physiotherapist can teach a person exercises to help them regain muscle control, coordination, and dexterity.
  • speech or language therapy: A speech or language therapist can help a person communicate more effectively following a stroke.
  • stroke support groups: A support group can provide practical and emotional support for people recovering from stroke.

Receiving prompt treatment for a stroke increases the likelihood of a full recovery. However, people who have had a stroke are at increased risk of having another.

According to a 2019 analysis of health insurance data in Germany, around 3% of people who have had a stroke will experience another within 90 days. The risk of another stroke is highest within the first year.

A person who has had a severe stroke may experience life-changing disabilities. They may require ongoing medical care as well as practical and emotional support.

According to the American Stroke Association, 80% of strokes are preventable.

Regular medical checkups are particularly important for people who have underlying conditions that increase their risk of stroke. Examples include:

  • high cholesterol
  • diabetes
  • heart disease
  • autoimmune disease

Adopting healthy lifestyle habits can also help prevent stroke. Examples include:

  • eating a balanced diet that is rich in fruits and vegetables
  • maintaining a healthy weight
  • performing around 2.5 hours of moderate intensity exercise each week
  • quitting smoking
  • limiting alcohol intake

A brain embolism is a blockage in an artery within the brain or in an artery that feeds oxygenated blood into the brain. Such blockages restrict blood flow to the brain, resulting in the rapid death of brain cells.

Brain embolisms can occur suddenly and require prompt treatment in order to limit brain damage. The FAST acronym is a useful way to spot the signs of stroke. FAST stands for “face, arms, speech, and time.” Anyone who thinks they may be experiencing a stroke should seek immediate medical attention.

The best way to prevent a stroke is to receive regular medical checkups and adopt a healthy lifestyle. This includes eating a healthy balanced diet and exercising regularly to maintain a healthy weight.