Condition Basics

What is a stroke?

A stroke is damage to the brain that occurs when a blood vessel in the brain bursts or is blocked by a blood clot. Without blood and the oxygen it carries, part of the brain starts to die. The part of the body controlled by the damaged area of the brain can't work properly.

Brain damage can start within minutes of a stroke. But quick treatment can help limit the damage and increase the chance of a full recovery.

What causes it?

What causes a stroke depends on the type of stroke.

There are two types of stroke:

• An ischemic (say "iss-KEE-mick") stroke is caused by a blood clot that blocks blood flow to the brain. A blood clot can form in an artery that supplies blood to the brain. Or a blood clot can form in another part of the body (often the heart) and travel through the bloodstream to the brain. Ischemic strokes are the most common type of stroke.
• A hemorrhagic (say "heh-muh-RAW-jick") stroke is caused by bleeding in or around the brain. It happens when an artery in the brain leaks or bursts. Hemorrhagic strokes are less common than ischemic strokes.

What are the symptoms?

FAST is a simple way to remember the main symptoms of stroke. These symptoms happen suddenly. So knowing what to look for helps you know when to call for medical help.

FAST stands for:

Other stroke symptoms include loss of balance or trouble walking, trouble seeing out of one or both eyes, sudden confusion, sudden trouble understanding simple statements, fainting, a seizure, and a sudden, severe headache.

When you know what stroke symptoms are, you will know when it's important to call for medical help. Quick treatment can limit damage from a stroke, and it may save your life or someone else's life.

How is it diagnosed?

The first test the doctor will do in the emergency room is a CT scan or MRI of the head. This can show if there is bleeding. Other tests may be done to check the stroke symptoms and check for other health problems.

How is a stroke treated?

For an ischemic stroke, you may get a clot-dissolving medicine called tissue plasminogen activator (TPA). You may get other medicines to prevent blood clots. A procedure may be done to remove the clot and restore blood flow.

For a hemorrhagic stroke, you may get medicine or a transfusion with parts of blood. This can stop the bleeding in the brain. You may have surgery or a procedure to repair an aneurysm or relieve pressure on the brain. You may get medicines to control blood pressure, brain swelling, and other problems.

After either kind of stroke, treatment shifts to preventing future strokes and to your recovery. A stroke rehabilitation program can help you recover and learn ways to adapt to changes caused by a stroke. Medicine and a heart-healthy lifestyle can help prevent another stroke. Your doctor will help you manage other conditions that put you at risk for another stroke.

Cause

What causes a stroke depends on the type of stroke.

There are two types of stroke: ischemic (say "iss-KEE-mick") strokes and hemorrhagic (say "heh-muh-RAW-jick") strokes. Ischemic strokes are the more common type.

Causes of ischemic stroke

An ischemic stroke is caused by a blood clot that blocks blood flow to the brain.

• A blood clot can form in an artery that supplies blood to the brain.
  • Blood clots usually form in arteries damaged by plaque buildup. This buildup process is called atherosclerosis.
• A blood clot can form in another part of the body (often the heart) and travel through the bloodstream to the brain. For example, clots may form:
  • After a heart attack.
  • As a result of other problems that change the blood flow through the heart. These conditions include abnormal heart rhythms (especially atrial fibrillation), heart valve problems, patent foramen ovale, atrial septal defects, and heart failure.
  • During or after certain types of surgeries and medical procedures.

Low blood pressure may also cause an ischemic stroke, but this is less common. Low blood pressure results in reduced blood flow to the brain. It may be caused by narrowed or diseased arteries, a heart attack, a large loss of blood, or a severe infection.

Causes of hemorrhagic stroke

A hemorrhagic stroke is caused by bleeding in or around the brain.

Other less common causes include head or neck injuries, certain diseases, and radiation treatment for cancer in the neck or brain.

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What Increases Your Risk

A risk factor is anything that makes you more likely to have a particular health problem.

Risk factors for stroke that you can manage or change include:

• Health problems like atrial fibrillation, diabetes, high blood pressure, high cholesterol, hardening of the arteries (atherosclerosis), and sickle cell disease.
• Smoking.
• Drinking too much alcohol or using recreational drugs. Your risk of harm from alcohol is low if you have 2 drinks or less per week, moderate if you have 3 to 6 drinks per week, and high if you have 7 or more drinks per week. Recreational drugs include cocaine, amphetamines, and cannabis.
• Being overweight.
• Not eating healthy foods.
• Not getting enough physical activity.
• Using hormone therapy. This includes taking hormone therapy for menopause or using birth control options with estrogen.

Risk factors you can't change include:

• Having a previous stroke.
• Family history of stroke.
• Being older.
• Being of Indigenous, African, or South Asian descent.
• Being female.
• Having certain problems during pregnancy, such as preeclampsia.
• Being past menopause.

Your doctor can help you know your risk. Then you and your doctor can talk about whether to take steps to lower it.

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Prevention

Here are some things you can do to help prevent a stroke.

• Manage health problems that raise your risk. These include atrial fibrillation, diabetes, high blood pressure, and high cholesterol.
• Have a heart-healthy lifestyle.
  • Don't smoke. If you need help quitting, talk to your doctor about stop-smoking programs and medicines. These can increase your chances of quitting for good.
  • Limit alcohol intake. Visit Canada’s Guidance on Alcohol and Health for more information.
  • Stay at a healthy weight. For more information, see Weight Management.
  • Be active. Get at least 2½ hours of moderate to vigorous exercise a 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. For more information, see Fitness and Exercise.
  • Eat heart-healthy foods. These include vegetables, fruits, nuts, beans, lean meat, fish, and whole grains. Limit sodium and sugar.
  • Try to limit stress. For more information, see Stress Management.
  • If you are diabetic, it is important to control your diabetes. To learn more about how to manage your diabetes, see Diabetes.
  • If you think you may have a problem with alcohol or drug use, talk to your doctor.
• If you use hormone therapy for menopause or hormonal birth control, talk with your doctor. Ask if these are right for you. They may raise the risk of stroke in some people.
• Decide with your doctor whether you will also take medicines to help lower your risk. For example, you and your doctor may decide you will take a medicine that prevents blood clots.

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Symptoms

Symptoms of a stroke happen suddenly. If you have symptoms of a stroke, even if they go away quickly, call 911 or other emergency services right away.

General symptoms of a stroke include:

• 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.
• Fainting.
• A seizure.

FAST is a simple way to remember the main symptoms of stroke. Recognizing these symptoms helps you know when to call for medical help.

FAST stands for:

Brain damage can begin within minutes. That's why it's so important to know the symptoms of stroke and to act fast. Quick treatment can help limit damage to the brain and increase the chance of a full recovery.

Symptoms can vary depending on whether the stroke is caused by a blood clot (ischemic stroke) or bleeding (hemorrhagic stroke). They also depend on where the stroke occurs in the brain, and how bad it is.

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What Happens

A stroke occurs when a blood vessel to the brain bursts or is blocked by a blood clot. The blood supply to part of the brain is reduced. Without blood and the oxygen it supplies, the nerve cells in that part of the brain die within minutes. As a result, the part of the body controlled by those cells cannot work properly.

The effects of a stroke may range from mild to severe. They may get better, or they may last the rest of your life. A stroke can affect many things, including vision, speech, behaviour, thought processes, and your ability to move.

Problems that can happen after a stroke

The problems you have after a stroke depend on what part of your brain was affected and how much damage the stroke caused. They may include problems with:

• Movement and senses. You may have trouble walking, grasping objects, or doing other tasks. Other symptoms may include joint pain or muscle stiffness or spasms. You may not be able to feel when something touches an affected body part. You may feel very tired.
• Speech and language. Your ability to speak, read, or write may be affected. Also, you may not be able to understand what someone else is saying.
• Memory and thinking. You may not be able to think clearly. You may have trouble focusing or remembering.
• Perception. It may be hard to do things like judge distance, size, position, and rate of movement.
• Emotions. It's common to feel fearful, anxious, angry, sad, or frustrated. Grief is also common.

When to Call a Doctor

Call 911 or other emergency services immediately if you have signs of a stroke:

• 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 911 if you have symptoms that seem like a stroke, even if they go away quickly.

Signs of a transient ischemic attack (TIA) are similar to signs of a stroke. But TIA symptoms usually disappear after 10 to 20 minutes, although they may last longer. There is no way to tell whether the symptoms are caused by a stroke or by TIA, so emergency medical care is needed for both conditions.

Call your doctor now if you:

• Are taking aspirin or other medicines that prevent blood clotting and you notice any signs of bleeding.
• Have a choking episode from food going down your windpipe.
• Have signs of a blood clot in a deep blood vessel. These include redness, warmth, and pain in a specific area of your arm or leg.

If you've had symptoms of a TIA in the past but you haven't talked with your doctor about it, call your doctor now.

Call your doctor for an appointment if you:

• Have a pressure injury.
• Notice that your affected arm or leg is getting stiffer or you can't straighten it (spasticity).
• Notice signs of a urinary tract infection. Signs may include fever, pain with urination, blood in urine, and low back (flank) pain.
• Are having trouble keeping your balance.

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Examinations and Tests

The first test the doctor will do in the emergency room is a CT scan or MRI of the head. This can show if there is bleeding in the brain. The results help the doctor know if the stroke is ischemic or hemorrhagic.

The doctor will also do an exam to check the stroke symptoms.

Other tests may include:

• Electrocardiogram (ECG, EKG) to check for heart problems.
• Blood tests to help your doctor make choices about your treatment and to check for conditions that may cause symptoms like those of a stroke. Tests may include:
  • Complete blood count (CBC).
  • Blood sugar.
  • Electrolytes.
  • Liver and kidney function.
  • Prothrombin time and INR (a test that measures how long it takes your blood to clot).

Later, you may have other tests to check for problems with your arteries or heart.

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Treatment Overview

Treatment depends on the type of stroke: ischemic or hemorrhagic.

Ischemic stroke.

For this type of stroke, treatment focuses on restoring blood flow to the brain.

• You may get a clot-dissolving medicine called tissue plasminogen activator (TPA). This medicine can improve recovery from a stroke, especially if it's given as soon as possible after the stroke happens. Doctors try to give this medicine within 4½ hours after symptoms start.^{footnote 1}
• You may also get aspirin or another antiplatelet medicine.
• In some cases, a procedure may be done to restore blood flow. The doctor uses a thin, flexible tube (catheter) and a tool inside the tube to remove the blood clot that caused the stroke. This procedure is called a thrombectomy.

Hemorrhagic stroke.

For this type of stroke, treatment focuses on controlling bleeding, reducing pressure in the brain, and stabilizing vital signs, especially blood pressure.

• To stop the bleeding, you may get medicine or a transfusion of parts of blood, such as plasma. These are given through an I.V.
• You will be closely watched for signs of increased pressure on the brain.
• If the bleeding is from a ruptured brain aneurysm, surgery or a procedure to repair the aneurysm may be done.
• In some cases, medicines may be given to control blood pressure, brain swelling, blood sugar levels, fever, and seizures.
• If a large amount of bleeding has occurred and symptoms are quickly getting worse, you may need surgery. The surgery can remove the blood that has built up inside the brain and lower pressure inside the head.

After either kind of stroke and after your condition is stable, treatment shifts to preventing future strokes and other problems and to your recovery.

• You may take medicines and have a heart-healthy lifestyle to help manage other health problems that put you at risk for another stroke. These conditions include high blood pressure and atrial fibrillation.
• If you have narrowed carotid arteries, you may choose to have a surgery or procedure to improve blood flow and help prevent another stroke.
• If you have an opening in the heart called a patent foramen ovale, you may choose to have a procedure to close it. This may help prevent another stroke.
• A stroke rehabilitation (rehab) program can help you recover and learn ways to adapt to the changes caused by a stroke. You can work toward getting back some of the skills and abilities you had before the stroke.

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Self-Care

Here are some ways to care for yourself after a stroke.

• Take your medicines exactly as prescribed. You may take a few medicines to help lower your risk of another stroke.
• Attend stroke rehabilitation (rehab) if recommended. Your rehab plan will be based on your goals and how the stroke affected you.
• You'll get instructions on how to manage specific problems that you might have because of the stroke.
• Manage other health problems. These include atrial fibrillation, diabetes, high blood pressure, and high cholesterol.
• Have a heart-healthy lifestyle.
  • Don't smoke.
  • If you drink alcohol, try to drink less. Limit alcohol to 2 drinks or less per week. Work with your doctor to find what is right for you.
  • Stay at a healthy weight.
  • Be active. Ask your doctor what type and level of activity is safe for you.
  • Eat heart-healthy foods. These include vegetables, fruits, nuts, beans, lean meat, fish, and whole grains. Limit sodium and sugar.
• Get vaccinated against COVID-19, influenza (flu), and pneumonia.

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Medicines

Blood thinners

One of the best things you can do to prevent another stroke is to take a medicine called a blood thinner. These medicines don't really thin your blood. They work by helping to prevent blood clots. Blood clots can cause a stroke if they block a blood vessel in the brain. So when you prevent blood clots, you help prevent a stroke.

Antiplatelets are a type of blood thinner. They help keep platelets from sticking together and forming blood clots. (A platelet is a type of blood cell.)

Examples of antiplatelets include:

• Aspirin.
• Aspirin combined with dipyridamole.
• Clopidogrel.

Another type of blood thinner, called an anticoagulant, may be used if you have a health problem that raises your risk of blood clots.

Examples of anticoagulants include:

• Direct oral anticoagulants.
• Warfarin.

Be sure to learn how to take your medicine safely. Blood thinners can cause serious bleeding problems.

Cholesterol medicines

Statins and other cholesterol medicines can lower the amount of cholesterol in your blood. If you have too much cholesterol, it starts to build up in blood vessels. And that's how most heart and blood flow problems, including strokes, start.

Statins also reduce inflammation around the cholesterol buildup. This may lower the risk that the buildup will break apart and cause a blood clot that can lead to a stroke.

Examples of statins include:

• Atorvastatin.
• Pravastatin.
• Simvastatin.

Other cholesterol medicines that can help lower stroke risk are cholesterol absorption inhibitors and PCSK9-inhibitors.

Blood pressure medicines

If you have high blood pressure, you may take medicines to lower it. High blood pressure can damage blood vessels. This damage can lead to hardening of the arteries, which can cause a stroke.

If you were taking blood pressure pills before, your doctor may have you keep taking them. Or your doctor may have you take a different type.

Blood pressure medicines include:

• ACE (angiotensin-converting enzyme) inhibitors.
• Angiotensin II receptor blockers (ARBs).
• Diuretics (water pills).

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Advice for Caregivers

Taking care of someone who has had a stroke can be hard for many reasons. Some concerns may include:

• Being afraid that they will have another stroke or won't be able to accept or overcome disabilities.
• Worrying that you're not prepared to care for someone who's just had a stroke. Or you may work or have your own health concerns that make it hard to care for another person.
• Becoming depressed over losing the lifestyle that you used to enjoy.
• Worrying about the costs of rehab and a loss of income.

If you have concerns, the stroke rehab team can help. The team can:

• Provide training. Before the person returns home, the rehab team will train you or other friends or family to help with therapy. You may learn to help them get up from a fall, eat, dress, get to the toilet, and do other activities.
• Help you find support. If you work or have your own health concerns that prevent you from being able to help, you may need in-home help. Or you may consider if a nursing home or assisted-living facility is an option. The rehab team can give you more information about local resources, such as in-home help. They may also be able to offer advice about provincial health plan or private insurance coverage.
• Provide counselling and emotional support. The rehab team can support you and help you adjust. They may suggest local support groups in your area.

Even if you can't provide physical help, your support is still key to their recovery.

Helping someone who had a stroke

Here are some ways to help.

• Realize that after a stroke, the person may be prone to strong emotional reactions. Remember that these are a result of the stroke. Try not to become too upset by them.
• Don't avoid someone who's had a stroke. Contact and support is very important to their recovery.
• Join a local support group. These groups provide a place where issues can be discussed in a supportive environment and an opportunity to meet others dealing with the same issues. Ask your doctor or the stroke rehab team about support groups in your area.
• Take care of yourself too. If you are a caregiver, you must stay healthy enough to help.

You are an important part of their recovery after a stroke.

• Give the person support and encouragement to participate in the decisions about their rehabilitation (rehab) program.
• Visit and talk with the person often.
• Participate in educational programs, and attend some of the rehab sessions.
• Help the person practice the skills they're learning.
• Work with the program staff to match the activities to what the person needs to do after returning home.
• Find out what the person can do independently and where help is needed. Avoid doing things for the person that they can do without help.

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