What is a transient ischemic attack (TIA)?
A transient ischemic attack (TIA), or ministroke, results from a temporary stoppage in the blood supply to the brain. TIAs usually only last 5 minutes but can be a sign of a major stroke to follow. It is a medical emergency.
Many people do not seek help for a TIA because the symptoms pass quickly. However, the Centers for Disease Control and Prevention (CDC) note that more than one-third of people who do not receive treatment for a TIA have a major stroke within a year.
Additional statistics suggest that 20% of those who have a TIA have a stroke within 3 months, and half of these will happen within 2 days of the TIA.
Knowing the symptoms of a TIA and getting help quickly may help prevent a more severe and possibly life threatening event.
In this article, learn more about what a TIA involves and which action to take if one occurs.
What is a TIA?
A TIA causes similar symptoms to those of a stroke, but it is temporary. The reduced blood supply usually only lasts for a few seconds, and the symptoms tend to last for minutes. Rarely, they can last for up to a few hours.
TIAs occur when a blood clot blocks blood flow and prevents oxygen from reaching the brain cells for a short while. When the clot breaks up or moves on, the symptoms tend to resolve. These events do not last long enough to cause permanent damage to brain cells.
The American Stroke Association urge people not to ignore a TIA, as it can be a warning sign for a major stroke.
Statistics suggest that TIAs affect around 2% of the population of the United States.
The symptoms of a TIA will depend on which part of the brain is not receiving adequate blood flow.
As with a major stroke, the acronym FAST (face, arms, speech, time) can help people remember the symptoms to look for:
- F = face: The eye or mouth may droop on one side, and the person may be unable to smile properly.
- A = arms: Arm weakness or numbness might make it hard to raise one or both arms or keep them raised.
- S = speech: The person’s speech may be slurred and garbled.
- T = time: Someone should call the emergency services at once if a person has one or more of these symptoms.
The person may also have:
- numbness or weakness, especially on one side of the body
- sudden confusion
- difficulty understanding what others are talking about
- vision problems
- problems with coordination
- difficulty walking
- a very bad headache
- a loss of consciousness, in some cases
TIA symptoms are temporary. They can last for a few minutes to a few hours, and they usually disappear completely after 24 hours.
However, it is essential to seek medical help at once if anyone has symptoms that may indicate a TIA because a major stroke may follow.
The same factors that lead to the temporary insufficiency of blood flow in a TIA can cause a stroke due to longer lasting blood flow reduction, which can lead to permanent brain damage.
Learn more about what to do if someone has a stroke here.
Conditions with similar symptoms
The symptoms of a TIA can resemble those of other conditions, such as:
- multiple sclerosis
- a hemorrhagic stroke or ischemic stroke
- fainting due to low blood pressure
Getting an accurate diagnosis can help a person access the right treatment to help lower the risk of a future stroke, even if the symptoms of the TIA have already passed.
A TIA occurs when there is a disruption in the supply of oxygen to the brain. This may be due to:
- atherosclerosis, in which fatty deposits cause the arteries to become harder, thicker, narrower, and less flexible
- blood clots due to heart disease, cardiovascular disease, or an irregular heart rhythm
- blood clots due to a blood condition, such as sickle cell disease
- an embolism or blood clot that has traveled from elsewhere in the body
- an air bubble in the bloodstream
The risk factors for a TIA are similar to those for a stroke. Some of these are preventable.
The following factors can increase the risk of experiencing a TIA:
- having a family history of stroke or TIA
- being 55 years or above
- being assigned male at birth
- being Black or Hispanic, compared with being non-Hispanic white
- having high blood pressure
- having cardiovascular disease
- smoking tobacco
- having diabetes
- getting low levels of exercise
- having high cholesterol levels
- eating a diet that is high in unhealthy fats and salt
- having high homocysteine levels
- having overweight or obesity
- having a type of heartbeat known as atrial fibrillation
Treatment will depend on the cause of the TIA. The following sections will look at some of the options.
A doctor may prescribe medications to lower the risk of another blood clot and a major stroke.
The options will depend on the cause of the TIA but commonly include:
- anti-platelet drugs to prevent clotting, such as include aspirin, ticlopidine (Ticlid), and clopidogrel (Plavix)
- anticoagulants such as warfarin (Coumadin) and heparin, which also help prevent clotting
- medications to manage high blood pressure, or hypertension
- drugs to help manage cholesterol levels
- medications to manage heart disease and regulate irregular heart rhythms
All of these drugs can have adverse effects, and they may also interact with other medications.
For this reason, people should inform a doctor about any other drugs they are taking, including over-the-counter medications, supplements, and herbal remedies.
If a person experiences adverse effects while using a drug, they should speak with a doctor. An alternative may be available.
In some cases, a doctor may recommend surgery to remove a blockage or part of a damaged artery.
Lifestyle measures and prevention
A number of lifestyle measures can help reduce the risk of experiencing a TIA or stroke. These include:
- avoiding or quitting smoking
- avoiding exposure to secondhand tobacco smoke
- eating a nutritious and varied diet, with plenty of fresh fruits and vegetables
- managing one’s intake of salt and unhealthy fats
- getting regular exercise
- avoiding the use of recreational drugs
- managing body weight, if appropriate
- following any treatment plan for heart disease, diabetes, or other conditions
It is best to discuss a suitable strategy with a healthcare professional before making any significant lifestyle changes, such as starting a new exercise regimen.
Anyone experiencing signs or symptoms of a TIA needs an immediate medical assessment to find out why it happened and how to prevent a recurrence or more severe event.
The symptoms can pass quickly and may no longer be present when the person reaches a doctor. However, a person who was present at the time may be able to help the individual explain the event to the doctor.
The doctor will likely:
- ask what happened and ask about any ongoing symptoms
- ask how long the symptoms lasted for and how they affected the person
- consider the individual’s personal and family medical history
- carry out a neurological examination, which may include memory and coordination tests
If the doctor believes that the person had a TIA, they may refer them to a neurologist for further testing.
Possible tests include:
- blood tests to check blood pressure, cholesterol levels, and clotting ability
- an electrocardiogram to measure the electrical activity and rhythms of the heart
- an echocardiogram to check the pumping action of the heart
- a chest X-ray to help rule out other conditions
- a CT scan to reveal any signs of an aneurysm, bleeding, or changes to blood vessels in the brain
- an MRI scan to help identify damage to the brain
The doctor may also ask the person to wear a Holter monitor for a few days or weeks to measure their heart rhythms over time.
When a person has a TIA, the symptoms may last for only a few minutes. However, it is essential to receive medical attention, as a TIA can be a warning sign for a major stroke.
Symptoms of a TIA include weakness and numbness on one side of the body, drooping on one side of the face, and difficulty speaking. If anyone experiences these symptoms, someone should call 911 immediately.
Treatment options following a TIA include lifestyle measures and the use of medication to reduce the risk of future blood clots.