Transient Ischemic Attack

Your brain is your body’s master control center. It directs your movements, mood, thoughts, ability to learn and reason. It is enormously efficient. But if blood flow to the brain is disrupted—even for a few minutes—your body will react. For example, you may notice slurring of your speech, trouble seeing, loss of balance or weakness—often on one side of body.

Unlike larger strokes, these “mini-strokes” are fleeting. They are called transient ischemic attacks (TIA). Fortunately, unlike larger strokes, a TIA usually doesn’t last long enough to cause any damage. However, it is a big red flag for more serious problems.

If left untreated, TIAs can be followed by more severe strokes that can result in permanent damage to your body, even death. In fact, about one in three people who have a TIA suffer a stroke within the next year. So don’t ignore it or wait to see whether your symptoms will go away.

If you’ve had a TIA, you need to work together with your health care team to map out a plan to prevent a larger stroke. This often means making lifestyle changes—for example, eating a healthful diet, exercising regularly and treating related problems like high blood pressure and high cholesterol. Remember, the choices you make each day can make a difference in your symptoms and general heart health.

Use this condition center to learn more about transient ischemic attacks, create a list of questions to ask your health care provider, and much more.

Topic Overview

What is a transient ischemic attack (TIA)?

Some people call a transient ischemic attack (TIA) a mini-stroke, because the symptoms are like those of a stroke but don’t last long. A TIA happens when blood flow to part of the brain is blocked or reduced, often by a blood clot. After a short time, blood flows again and the symptoms go away. With a stroke, the blood flow stays blocked, and the brain has permanent damage.

A TIA is a warning: it means you are likely to have a stroke in the future. If you think you are having a TIA, call 112. Early treatment can help prevent a stroke. If you think you have had a TIA but your symptoms have gone away, you still need to call your doctor right away.

What are the symptoms?

Symptoms of a TIA are the same as symptoms of a stroke. But symptoms of a TIA occur suddenly and don’t last very long. Most of the time, they go away in 10 to 20 minutes. They may include:

• Sudden numbness, tingling, weakness, or paralysis in your face, arm, or leg, especially on only one side of your body.
• Sudden vision changes.
• Sudden trouble speaking.
• Sudden confusion or trouble understanding simple statements.
• Sudden problems with walking or balance.
• A sudden, severe headache that is different from past headaches

What causes a transient ischemic attack?

A blood clot is the most common cause of a TIA. Blood clots can be the result of hardening of the arteries (atherosclerosis), heart attack, or abnormal heart rhythms. Brain cells are affected within seconds of the blockage. That causes symptoms in the parts of the body controlled by those cells. After the clot dissolves, blood flow returns, and the symptoms go away.

Sometimes a TIA is caused by a sharp drop in blood pressure that reduces blood flow to the brain. This is called a “low-flow” TIA. It is not as common as other types.

What tests do you need after a TIA?

Your doctor will do tests to look at your heart and blood vessels. You may need:

• Tests that show pictures of your brain and blood vessels, such as a CT scan, an MRI, a magnetic resonance angiogram (MRA), or an angiogram.
• A test that uses sound to check your blood flow (Doppler ultrasound).
• An echocardiogram (echo)to check your heart’s shape and its blood flow.
• An electrocardiogram (EKG, ECG)to measure your heart rhythm.
• Blood tests, including a complete blood countand a fasting blood test to check for problems that could be causing your symptoms.

Your doctor will also check to see if something else is causing your symptoms.

How is a TIA treated?

Your doctor will start you on medicines to help prevent a stroke. You may need to take several medicines.

If tests show that the blood vessels (carotid arteries) in your neck are too narrow, you may need surgery to open them up (carotid endarterectomy). This can help prevent blood clots that block blood flow to your brain.

Another type of surgery is carotid artery stenting. During this surgery, the doctor puts a small tube called a stent inside your carotid artery. This helps keep the artery open. Carotid artery stenting is not as common as endarterectomy.

How can you prevent another TIA or stroke?

After you have had a TIA, you are at risk for having another TIA or a stroke. But you can make some important lifestyle changes that can reduce your risk of stroke and improve your overall health.

Treat any health problems you have

• Manage high blood pressure or high cholesterol by working with your doctor.
• Manage diabetes. Keep your blood sugar levels within a target range.
• If your doctor recommends that you take aspirin or a blood thinner, take it. This can help prevent a stroke.
• Take your medicine exactly as prescribed. Call your doctor if you think you are having a problem with your medicine.

Adopt a healthy lifestyle

• Don’t smoke or allow others to smoke around you.
• Limit alcohol to 2 drinks a day for men and 1 drink a day for women.
• Stay at a healthy weight. Being overweight makes it more likely that you will develop high blood pressure, heart problems, and diabetes. These conditions make a stroke more likely.
• Do activities that raise your heart rate. Get at least 30 minutes of exercise on most days of the week. Walking is a good choice. You also may want to do other activities, such as running, swimming, cycling, or playing tennis or team sports.
• Eat heart-healthy foods. These include fruits, vegetables, high-fiber foods, fish, and foods that are low in sodium, saturated fat, trans fat, and cholesterol.

Frequently Asked Questions

Learning about TIA:	· What is a transient ischemic attack (TIA)? · What causes a TIA? · What increases my risk for a TIA? · Can a TIA be prevented? · Who is affected by TIAs?
Being diagnosed:	· What are the symptoms of a TIA? · What tests will I need?
Getting treatment:	· What is the treatment for a TIA? · What medicines will I need? · Will I need surgery?
Ongoing concerns:	· Will a TIA lead to a stroke?
Living with TIA:	· Will I have to make lifestyle changes after a TIA? · How can I eat a heart-healthy diet?

Transient Ischemic Attack (TIA)

Cause

Blood clots that temporarily block blood flow to the brain are the most common cause of transient ischemic attacks (TIAs). Blood clots may develop for a variety of reasons.

• A blood clot can form in an artery that supplies blood to the brain.
  • Blood clots usually form in arteries damaged by plaquebuildup, which is a process called atherosclerosis. High blood pressure may damage arteries  and cause plaque to build up.
  • Long-standing high blood pressure or diabetes may damage smaller blood vessels in the brain, causing a clot to form within the blood vessels and block blood flow.
• A blood clot can form in another part of the body (often the heart) and travel through the bloodstream to an artery that supplies blood to the brain. For example, clots may form:
  • After a heart attack.
  • As a result of other conditions that alter how blood flows through the heart. These conditions include abnormal heart rhythms (especially atrial fibrillation), heart valve problems, patent foramen ovale, atrial septal defects, and heart failure.

Also, an artery that is partially blocked with plaque can reduce blood flow to the brain and cause symptoms.

Rare causes of blood clots that can cause a TIA include:

• Clumps of bacteria, tumor cells, or air bubbles that move through the bloodstream.
• Conditions that cause blood cells to stick together. For example, having too many red blood cells (polycythemia), abnormal clotting factors, or abnormally shaped red blood cells, such as those caused by sickle cell disease, may cause blood clots to form.
• Inflammation in the blood vessels, which may develop from conditions such as syphilis, tuberculosis, or other inflammatory diseases.
• A head or neck injury that results in damage to blood vessels in the head or neck.
• A tear in the wall of a blood vessel located in the neck.

What Happens

A transient ischemic attack (TIA) is a warning sign that a stroke may soon follow. Any symptoms of a TIA need to be treated as an emergency.

• After a TIA, 9 to 17 out of 100 people will have a stroke in less than 90 days.¹The risk of stroke is highest in the first 30 days after a TIA.
• A TIA happens before about 15 out of 100 strokes.¹

A TIA also may signal an increased risk for a heart attack. Atherosclerosis, which is hardening of the arteries, affects blood vessels throughout the body, including arteries that supply blood to the heart and brain. Atherosclerosis that affects the blood vessels in the heart (coronary arteries) may cause chest pain or a heart attack.

What Increases Your Risk

The risk factors (things that increase risk) for transient ischemic attack (TIA) and stroke include those you can treat or change and those you can’t change.

Risk factors you can treat or change include:

• High blood pressure (hypertension).
• Atrial fibrillation.
• High cholesterol.
• Heavy use of alcohol.
• Being overweight.
• Physical inactivity.

Risk factors you cannot change include:

• The risk of TIA and stroke increases with age.
• African Americans, Native Americans, and Alaskan Natives have a higher risk than those of other races.
• TIA and stroke are more common in men than women until age 75, when more women than men have strokes. Because women live longer than men, more women have strokes each year.
• Family history. The risk for TIA and stroke is greater if a parent, brother, or sister has had a stroke or a transient ischemic attack (TIA).
• History of stroke or TIA.

When To Call a Doctor

Call 112 or other emergency services immediately if you have:

• Sudden numbness, tingling, weakness, or loss of movement in your face, arm, or leg, especially on only one side of your body.
• Sudden vision changes.
• Sudden trouble speaking.
• Sudden confusion or trouble understanding simple statements.
• Sudden problems with walking or balance.
• A sudden, severe headache that is different from past headaches.

Call your doctor immediately if you have:

• Recently had symptoms of a transient ischemic attack (TIA), even if the symptoms have completely disappeared.
• Had a TIA or stroke while taking aspirin or other medicine that prevents blood clots, and you notice any signs of bleeding.

Call your doctor today if you think you have had a TIA in the past and have not yet talked with your doctor about your symptoms.

Who to see

The following doctors can diagnose and treat a transient ischemic attack (TIA):

• Family medicine doctor
• Neurologist
• Emergency medicine specialist
• Internist

Other specialists may be consulted if you need surgery or have other health problems:

• Neurosurgeon
• Cardiologist
• Vascular surgeon (one who specializes in surgery of the blood vessels)

To prepare for your appointment, see the topic Making the Most of Your Appointment.

Exams and Tests

Immediate evaluation is recommended if you have had or are having a transient ischemic attack (TIA). The purpose of evaluation is to:

• Check for another cause of your symptoms, such as a stroke, low blood sugar (if you have diabetes), or Bell’s palsy.
• Look for a blood clot.
• Find out whether you need surgery to reopen a blocked artery (carotid endarterectomy).
• Find out whether you need medicines to prevent blood clots.

If your TIA symptoms have completely disappeared, the results of a physical exam will be normal, and the diagnosis of a TIA usually will be based on your medical history and certain tests.

Tests to detect a TIA

If a TIA is suspected, the doctor may want to do tests, such as a:

• CT scan of the head, to check for bleeding in the brain when symptoms of a TIA are occurring and to check for evidence of a stroke or other disease, such as a tumor.
• MRI scan, to check for damage to the brain from a stroke.

Tests to find the cause of a TIA

Further tests are often done to identify the cause of the TIA. If blockage of the carotid arteries is suspected, you may have tests such as:

• A Doppler ultrasound.
• A magnetic resonance angiogram (MRA).
• An angiogram of your head and neck. An angiogram can help showthe source of clots that cause the TIA.

TIA symptoms may be due to blood clots caused by a heart problem. If heart problems are suspected, you may have tests such as a:

• Chest X-rayto assess the size and shape of your heart.
• Electrocardiogram (ECG, EKG)or Holter monitoring or ambulatory EKG to assess heart rhythm.
• Echocardiogram (echo)to examine the shape of the heart chambers and blood flow through them.
• Cholesterol and triglycerides teststo check the level of these blood fats that can increase your risk for blood clots and hardening of the arteries.

You may have other blood tests, such as a complete blood count (CBC), chemistry screen, and prothrombin time based on your age and medical history. Your doctor will use these tests to look for other causes of the TIA.

Treatment Overview

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Getting help for a TIA

If you have symptoms of a TIA, get medical help right away.

If you had symptoms of a TIA but you feel better now, you still need to see a doctor right away. A TIA is a sign that a stroke may soon follow. Prompt medical treatment may prevent a stroke.

Treatment for a TIA

If you’ve had a transient ischemic attack (TIA), you may need further testing and treatment after you’ve been checked by your doctor. If you have a high risk of stroke, you may have to stay in the hospital for treatment.

Your treatment for a TIA may include taking medicines to prevent a stroke or having surgery to reopen narrow arteries.

Medicines may include aspirin, clopidogrel, dipyridamole with aspirin, or warfarin.

If your carotid arteries are significantly blocked, you may need surgery to reopen the narrowed arteries (carotid endarterectomy).

Preventing another TIA or stroke

Your treatment will also focus on preventing another TIA or stroke. This may include:

• Reducing high blood pressure, the most common risk factor for stroke, by making changes to your diet and taking medicines that lower blood pressure.
• Taking aspirin or another antiplatelet medicine to prevent strokes.
• Controlling diabetes. Your doctor will advise that you try to keep your blood sugar levels in a target range. To do this, you may need to take oral medicines or insulin. Eating a healthy diet and getting plenty of exercise will also help.
• Getting a flu shot every year to help you avoid getting sick from the flu.

You may also need to make lifestyle changes such as quitting smoking, eating heart-healthy foods, and being more active.

Prevention

You can help prevent a transient ischemic attack (TIA) or stroke by controlling your risk factors for stroke.

Know your stroke risk

These are some of the common risk factors for stroke:

• You smoke.
• You have high blood pressure.
• Your cholesterol level is higher than average.
• You have diabetes.
• You are overweight.
• You don’t exercise on a regular basis.
• You drink large amountsof alcohol.

Treat any health problems you have

• Manage high blood pressure or high cholesterol by working with your doctor.
• Manage diabetes. Keep your blood sugar levels within a target range.
• If your doctor advises you to take aspirin or a blood thinner, take it. This can help prevent a stroke.
• Take your medicine exactly as prescribed. Call your doctor if you think you are having a problem with your medicine.

Adopt a healthy lifestyle

• Don’t smoke or allow others to smoke around you. For more information, see the topic Quitting Smoking.
• Limit alcohol to 2 drinksa day for men and 1 drink a day for women.
• Stay at a healthy weight. Being overweight makes it more likely you will develop high blood pressure, heart problems, and diabetes. These conditions make a stroke more likely.
• Do activities that raise your heart rate. Get at least 30 minutes of exercise on most days of the week. Walking is a good choice. You also may want to do other activities, such as running, swimming, cycling, or playing tennis or team sports.

Fitness: Walking for Wellness

• Eat heart-healthy foods. These include fruits, vegetables, high-fiber foods, and foods that are low in sodium, saturated fat, trans fat, and cholesterol. Eat fish at least 2 times each week. Oily fish, which contain omega-3 fatty acids, are best. These fish include salmon, mackerel, lake trout, herring, and sardines.
  • Dietary Approaches to Stop Hypertension (DASH) diet
  • Therapeutic Lifestyle Changes (TLC) diet
  • American Heart Association diet
  • Mediterranean-style diet

Home Treatment

Home treatment is not appropriate for a transient ischemic attack (TIA). If you think you are having a TIA, don’t ignore the symptoms, and don’t try to manage them at home. If you had symptoms of a TIA but they went away, you still need to see a doctor right away.

Seek emergency medical care when symptoms first appear. Prompt treatment may keep you from having a stroke.

You can care for yourself at home by adopting healthy habits that help you prevent another TIA or stroke. To learn more, see Prevention.

Medications

Your doctor will probably prescribe several medicines after you have had a transient ischemic attack (TIA). Medicines to prevent blood clots are typically used, because blood clots can cause TIAs and strokes.

The types of medicines that prevent clotting are:

• Antiplatelet medicines.
• Anticoagulant medicines.

Cholesterol-lowering and blood pressure-lowering medicines are also used to prevent TIAs and strokes.

Antiplatelet medicines

Antiplatelet medicines keep platelets in the blood from sticking together.

• Aspirin (for example, Bayer) is most often used to prevent TIAs and strokes.
• Aspirin combined with dipyridamole (Aggrenox) is a safe and effective alternative to aspirin.
• Clopidogrel (Plavix) may be used for people who cannot take aspirin.

Anticoagulants

Anticoagulants such as warfarin (for example, Coumadin) prevent blood clots from forming and keep existing blood clots from getting bigger. You may need to take this type of medicine after a TIA if you have atrial fibrillation or another condition that makes you more likely to have a stroke. For more information, see the topic Atrial Fibrillation.

Statins

Statins lower cholesterol and can greatly reduce the risk of stroke in people who have had a TIA. Statins even protect against stroke in people who don’t have heart disease or high cholesterol.²

Blood pressure medicines

If you have high blood pressure, your doctor may want you to take medicines to lower it. Blood pressure medicines include:

• Angiotensin II receptor blockers (ARBs).
• Angiotensin-converting enzyme (ACE) inhibitors.
• Beta-blockers.
• Calcium channel blockers.
• Diuretics.

Surgery

If you have a serious blockage in the carotid arteries in your neck, you may need a carotid endarterectomy. During this surgery, a surgeon removes plaque buildup in the carotid arteries to reduce the risk of transient ischemic attack (TIA) or stroke.

The benefits and risks of this surgery must be carefully weighed, because the surgery itself may cause a stroke. Your need to have carotid endarterectomy depends on whether you have had a TIA or stroke and how much your carotid arteries have narrowed.

Carotid artery stenting (also called carotid angioplasty and stenting) is sometimes done as an alternative to surgery to prevent transient ischemic attack (TIA) or stroke. In this procedure, a doctor threads a thin tube called a catheter through an artery in the groin and up to the carotid artery in your neck. The doctor then uses a tiny balloon to enlarge the narrowed portion of the artery and places a stent to keep the artery open. Carotid artery stenting is not as common as carotid endarterectomy.