Published on February 14, 2024

Stroke

Overview

An ischemic stroke occurs when the blood supply to part of the brain is blocked or reduced. This prevents brain tissue from getting oxygen and nutrients. Brain cells begin to die in minutes. Another type of stroke is a hemorrhagic stroke. It occurs when a blood vessel in the brain leaks or bursts and causes bleeding in the brain. The blood increases pressure on brain cells and damages them.

A stroke is a medical emergency. It's crucial to get medical treatment right away. Getting emergency medical help quickly can reduce brain damage and other stroke complications.

The good news is that fewer Americans die of stroke now than in the past. Effective treatments also can help prevent disability from stroke.

Symptoms

If you or someone you're with may be having a stroke, pay attention to the time the symptoms began. Some treatments are most effective when given soon after a stroke begins.

Symptoms of stroke include:

  • Trouble speaking and understanding what others are saying. A person having a stroke may be confused, slur words or may not be able to understand speech.
  • Numbness, weakness or paralysis in the face, arm or leg. This often affects just one side of the body. The person can try to raise both arms over the head. If one arm begins to fall, it may be a sign of a stroke. Also, one side of the mouth may droop when trying to smile.
  • Problems seeing in one or both eyes. The person may suddenly have blurred or blackened vision in one or both eyes. Or the person may see double.
  • Headache. A sudden, severe headache may be a symptom of a stroke. Vomiting, dizziness and a change in consciousness may occur with the headache.
  • Trouble walking. Someone having a stroke may stumble or lose balance or coordination.

When to see a doctor

Seek immediate medical attention if you notice any symptoms of a stroke, even if they seem to come and go or they disappear completely. Think "FAST" and do the following:

  • Face. Ask the person to smile. Does one side of the face droop?
  • Arms. Ask the person to raise both arms. Does one arm drift downward? Or is one arm unable to rise?
  • Speech. Ask the person to repeat a simple phrase. Is the person's speech slurred or different from usual?
  • Time. If you see any of these signs, call 911 or emergency medical help right away.

Call 911 or your local emergency number immediately. Don't wait to see if symptoms stop. Every minute counts. The longer a stroke goes untreated, the greater the potential for brain damage and disability.

If you're with someone you suspect is having a stroke, watch the person carefully while waiting for emergency assistance.

Causes

There are two main causes of stroke. An ischemic stroke is caused by a blocked artery in the brain. A hemorrhagic stroke is caused by leaking or bursting of a blood vessel in the brain. Some people may have only a temporary disruption of blood flow to the brain, known as a transient ischemic attack (TIA). A TIA doesn't cause lasting symptoms.

Ischemic stroke

This is the most common type of stroke. It happens when the brain's blood vessels become narrowed or blocked. This causes reduced blood flow, known as ischemia. Blocked or narrowed blood vessels can be caused by fatty deposits that build up in blood vessels. Or they can be caused by blood clots or other debris that travel through the bloodstream, most often from the heart. An ischemic stroke occurs when fatty deposits, blood clots or other debris become lodged in the blood vessels in the brain.

Some early research shows that COVID-19 infection may increase the risk of ischemic stroke, but more study is needed.

Hemorrhagic stroke

Hemorrhagic stroke occurs when a blood vessel in the brain leaks or ruptures. Bleeding inside the brain, known as a brain hemorrhage, can result from many conditions that affect the blood vessels. Factors related to hemorrhagic stroke include:

  • High blood pressure that's not under control.
  • Overtreatment with blood thinners, also known as anticoagulants.
  • Bulges at weak spots in the blood vessel walls, known as aneurysms.
  • Head trauma, such as from a car accident.
  • Protein deposits in blood vessel walls that lead to weakness in the vessel wall. This is known as cerebral amyloid angiopathy.
  • Ischemic stroke that leads to a brain hemorrhage.

A less common cause of bleeding in the brain is the rupture of an arteriovenous malformation (AVM). An AVM is an irregular tangle of thin-walled blood vessels.

Transient ischemic attack

A transient ischemic attack (TIA) is a temporary period of symptoms similar to those of a stroke. But a TIA doesn't cause permanent damage. A TIA is caused by a temporary decrease in blood supply to part of the brain. The decrease may last as little as five minutes. A transient ischemic attack is sometimes known as a ministroke.

A TIA occurs when a blood clot or fatty deposit reduces or blocks blood flow to part of the nervous system.

Seek emergency care even if you think you've had a TIA. It's not possible to tell if you're having a stroke or TIA based only on the symptoms. If you've had a TIA, it means you may have a partially blocked or narrowed artery leading to the brain. Having a TIA increases your risk of having a stroke later.

Ischemic stroke

An ischemic stroke occurs when a blood clot, known as a thrombus, blocks or plugs an artery leading to the brain. A blood clot often forms in arteries damaged by a buildup of plaques, known as atherosclerosis. It can occur in the carotid artery of the neck as well as other arteries.

Risk factors

Many factors can increase the risk of stroke. Potentially treatable stroke risk factors include:

Lifestyle risk factors

  • Being overweight or obese.
  • Physical inactivity.
  • Heavy or binge drinking.
  • Use of illegal drugs such as cocaine and methamphetamine.

Medical risk factors

  • High blood pressure.
  • Cigarette smoking or secondhand smoke exposure.
  • High cholesterol.
  • Diabetes.
  • Obstructive sleep apnea.
  • Cardiovascular disease, including heart failure, heart defects, heart infection or irregular heart rhythm, such as atrial fibrillation.
  • Personal or family history of stroke, heart attack or transient ischemic attack.
  • COVID-19 infection.

Other factors associated with a higher risk of stroke include:

  • Age — People age 55 or older have a higher risk of stroke than do younger people.
  • Race or ethnicity — African American and Hispanic people have a higher risk of stroke than do people of other races or ethnicities.
  • Sex — Men have a higher risk of stroke than do women. Women are usually older when they have strokes, and they're more likely to die of strokes than are men.
  • Hormones — Taking birth control pills or hormone therapies that include estrogen can increase risk.

Complications

A stroke can sometimes cause temporary or permanent disabilities. Complications depend on how long the brain lacks blood flow and which part is affected. Complications may include:

  • Loss of muscle movement, known as paralysis. You may become paralyzed on one side of the body. Or you may lose control of certain muscles, such as those on one side of the face or one arm.
  • Trouble talking or swallowing. A stroke might affect the muscles in the mouth and throat. This can make it hard to talk clearly, swallow or eat. You also may have trouble with language, including speaking or understanding speech, reading or writing.
  • Memory loss or trouble thinking. Many people who have had strokes experience some memory loss. Others may have trouble thinking, reasoning, making judgments and understanding concepts.
  • Emotional symptoms. People who have had strokes may have more trouble controlling their emotions. Or they may develop depression.
  • Pain. Pain, numbness or other feelings may occur in the parts of the body affected by stroke. If a stroke causes you to lose feeling in the left arm, you may develop a tingling sensation in that arm.
  • Changes in behavior and self-care. People who have had strokes may become more withdrawn. They also may need help with grooming and daily chores.

Prevention

You can take steps to prevent a stroke. It's important to know your stroke risk factors and follow the advice of your healthcare professional about healthy lifestyle strategies. If you've had a stroke, these measures might help prevent another stroke. If you have had a transient ischemic attack (TIA), these steps can help lower your risk of a stroke. The follow-up care you receive in the hospital and afterward also may play a role.

Many stroke prevention strategies are the same as strategies to prevent heart disease. In general, healthy lifestyle recommendations include:

  • Control high blood pressure, known as hypertension. This is one of the most important things you can do to reduce your stroke risk. If you've had a stroke, lowering your blood pressure can help prevent a TIA or stroke in the future. Healthy lifestyle changes and medicines often are used to treat high blood pressure.
  • Lower the amount of cholesterol and saturated fat in your diet. Eating less cholesterol and fat, especially saturated fats and trans fats, may reduce buildup in the arteries. If you can't control your cholesterol through dietary changes alone, you may need a cholesterol-lowering medicine.
  • Quit tobacco use. Smoking raises the risk of stroke for smokers and nonsmokers exposed to secondhand smoke. Quitting lowers your risk of stroke.
  • Manage diabetes. Diet, exercise and losing weight can help you keep your blood sugar in a healthy range. If lifestyle factors aren't enough to control blood sugar, you may be prescribed diabetes medicine.
  • Maintain a healthy weight. Being overweight contributes to other stroke risk factors, such as high blood pressure, cardiovascular disease and diabetes.
  • Eat a diet rich in fruits and vegetables. Eating five or more servings of fruits or vegetables every day may reduce the risk of stroke. The Mediterranean diet, which emphasizes olive oil, fruit, nuts, vegetables and whole grains, may be helpful.
  • Exercise regularly. Aerobic exercise reduces the risk of stroke in many ways. Exercise can lower blood pressure, increase the levels of good cholesterol, and improve the overall health of the blood vessels and heart. It also helps you lose weight, control diabetes and reduce stress. Gradually work up to at least 30 minutes of moderate physical activity on most or all days of the week. The American Heart association recommends getting 150 minutes of moderate-intensity aerobic activity or 75 minutes of vigorous aerobic activity a week. Moderate intensity activities can include walking, jogging, swimming and bicycling.
  • Drink alcohol in moderation, if at all. Drinking large amounts of alcohol increases the risk of high blood pressure, ischemic strokes and hemorrhagic strokes. Alcohol also may interact with other medicines you're taking. However, drinking small to moderate amounts of alcohol may help prevent ischemic stroke and decrease the blood's clotting tendency. A small to moderate amount is about one drink a day. Talk to your healthcare professional about what's appropriate for you.
  • Treat obstructive sleep apnea (OSA). OSA is a sleep disorder that causes you to stop breathing for short periods several times during sleep. Your healthcare professional may recommend a sleep study if you have symptoms of OSA. Treatment includes a device that delivers positive airway pressure through a mask to keep the airway open while you sleep.
  • Don't use illicit drugs. Certain illicit drugs such as cocaine and methamphetamine are established risk factors for a TIA or a stroke.

Preventive medicines

If you have had an ischemic stroke, you may need medicines to help lower your risk of having another stroke. If you have had a TIA, medicines can lower your risk of having a stroke in the future. These medicines may include:

  • Anti-platelet drugs. Platelets are cells in the blood that form clots. Anti-platelet medicines make these cells less sticky and less likely to clot. The most commonly used anti-platelet medicine is aspirin. Your healthcare professional can recommend the right dose of aspirin for you.

    If you've had a TIA or minor stroke, you may take both an aspirin and an anti-platelet medicine such as clopidogrel (Plavix). These medicines may be prescribed for a period of time to reduce the risk of another stroke. If you can't take aspirin, you may be prescribed clopidogrel alone. Ticagrelor (Brilinta) is another anti-platelet medicine that can be used for stroke prevention.

  • Blooding-thinning medicines, known as anticoagulants. These medicines reduce blood clotting. Heparin is a fast-acting anticoagulant that may be used short-term in the hospital.

    Slower acting warfarin (Jantoven) may be used over a longer term. Warfarin is a powerful blood-thinning medicine, so you need to take it exactly as directed and watch for side effects. You also need regular blood tests to monitor warfarin's effects.

    Several newer blood-thinning medicines are available to prevent strokes in people who have a high risk. These medicines include dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis) and edoxaban (Savaysa). They work faster than warfarin and usually don't require regular blood tests or monitoring by your healthcare professional. These medicines also are associated with a lower risk of bleeding complications compared to warfarin.

Diagnosis

During a stroke, things move quickly once you get to the hospital. Your emergency team works to learn what type of stroke you're having. You'll likely have a CT scan or other imaging test soon after arrival. Healthcare professionals also need to rule out other possible causes of your symptoms, such as a brain tumor or a drug reaction.

Tests

Some of the tests you may have include:

  • A physical exam. A healthcare professional does several tests, including listening to your heart and checking your blood pressure. A neurological exam looks at how a potential stroke is affecting your nervous system.
  • Blood tests. You may need tests to check how fast your blood clots and whether your blood sugar is too high or low. You also may be tested to see if you have an infection.
  • Computerized tomography (CT) scan. A CT scan uses a series of X-rays to create a detailed image of your brain. A CT scan can show bleeding in the brain, an ischemic stroke, a tumor or other conditions. You might have a dye injected into your bloodstream to view the blood vessels in the neck and brain in greater detail. This type of test is called a computerized tomography angiography.
  • Magnetic resonance imaging (MRI). An MRI uses powerful radio waves and a magnetic field to create a detailed view of the brain. The test can detect brain tissue damaged by an ischemic stroke and brain hemorrhages. Sometimes a dye is injected into a blood vessel to view the arteries and veins and highlight blood flow. This test is called magnetic resonance angiography or magnetic resonance venography.
  • Carotid ultrasound. In this test, sound waves create detailed images of the inside of the carotid arteries in the neck. A carotid ultrasound can show buildup of fatty deposits called plaques and blood flow in the carotid arteries.
  • Cerebral angiogram. This test is less common, but it provides a detailed view of arteries in the brain and neck. A thin, flexible tube called a catheter is inserted through a small incision, usually in the groin. The tube is guided through the major arteries and into the carotid or vertebral artery in the neck. Then a dye is injected into the blood vessels to make the arteries visible under X-ray imaging.
  • Echocardiogram. An echocardiogram uses sound waves to create detailed images of the heart. An echocardiogram can find a source of clots in the heart that may have traveled to the brain and caused a stroke.
CT scan of brain tissue damaged by stroke

CT scan showing brain tissue damaged by stroke

Cerebral angiogram

A cerebral angiogram showing a carotid aneurysm associated with stroke

Treatment

Emergency treatment depends on whether you're having an ischemic or hemorrhagic stroke. During an ischemic stroke, blood vessels in the brain are blocked or narrowed. During a hemorrhagic stroke, there's bleeding into the brain.

Ischemic stroke

To treat an ischemic stroke, blood flow must quickly be restored to the brain. This may be done with:

  • Emergency IV medicine. An IV medicine that can break up a clot has to be given within 4.5 hours from when symptoms began. The sooner the medicine is given, the better. Quick treatment improves your chances of survival and may reduce complications.

    An IV injection of recombinant tissue plasminogen activator (TPA) is the gold standard treatment for ischemic stroke. The two types of TPA are alteplase (Activase) and tenecteplase (TNKase). An injection of TPA is usually given through a vein in the arm within the first three hours. Sometimes, TPA can be given up to 4.5 hours after stroke symptoms started.

    This medicine restores blood flow by dissolving the blood clot causing the stroke. By quickly removing the cause of the stroke, it may help people recover more fully from a stroke. Your healthcare professional considers certain risks, such as potential bleeding in the brain, to determine whether TPA is appropriate for you.

  • Emergency endovascular procedures. Healthcare professionals sometimes treat ischemic strokes directly inside the blocked blood vessel. Endovascular therapy has been shown to improve outcomes and reduce long-term disability after ischemic stroke. These procedures must be performed as soon as possible:
    • Medicines delivered directly to the brain. During this procedure, a long, thin tube called a catheter is inserted through an artery in the groin. The catheter is moved through the arteries to the brain to deliver TPA directly where the stroke is happening. The time window for this treatment is somewhat longer than for injected TPA but is still limited.
    • Removing the clot with a stent retriever. A device attached to a catheter can directly remove the clot from the blocked blood vessel in the brain. This procedure is especially helpful for people with large clots that can't be completely dissolved with TPA. This procedure often is performed in combination with injected TPA.

The time window when these procedures can be considered has been expanding due to newer imaging technology. Perfusion imaging tests done with CT or MRI help determine if that someone may benefit from endovascular therapy.

Other procedures

Your healthcare professional may recommend a procedure to open up an artery that is narrowed by plaque. This type of procedure is done to lower your risk of having another stroke or transient ischemic attack. Options vary, but include:

  • Carotid endarterectomy. Carotid arteries are the blood vessels that run along each side of the neck, supplying the brain with blood. This surgery removes the plaque blocking a carotid artery and may reduce the risk of ischemic stroke. A carotid endarterectomy also involves risks, especially for people with heart disease or other medical conditions.
  • Angioplasty and stents. In an angioplasty, a surgeon threads a catheter to the carotid arteries through an artery in the groin. A balloon is then inflated to expand the narrowed artery. Then a stent can be inserted to support the opened artery.

Hemorrhagic stroke

Emergency treatment of hemorrhagic stroke focuses on controlling the bleeding and reducing pressure in the brain caused by excess fluid.

Emergency measures

If you take blood-thinning medicines to prevent blood clots, you may be given treatment to counteract the blood thinners' effects. These treatments include medicines or a transfusion of blood products. Medicines also can lower the pressure in your brain, lower blood pressure, prevent spasms of the blood vessels and prevent seizures.

Surgery

If the area of bleeding is large, you may need surgery to remove the blood and relieve pressure on your brain. Surgery also may be used to repair blood vessel damage associated with hemorrhagic strokes.

Your healthcare professional may recommend one of these procedures if an aneurysm, arteriovenous malformation (AVM) or other blood vessel condition caused the stroke.

  • Surgical clipping. A surgeon places a tiny clamp at the base of an aneurysm to stop blood flow to it. An aneurysm is a bulge at a weak spot in a blood vessel. The clamp can keep the aneurysm from bursting. Or the clamp can keep an aneurysm that has recently burst from bleeding again.
  • Coiling, also known as endovascular embolization. A catheter is inserted into an artery in the groin and guided to the brain. Using the catheter, a surgeon places tiny coils into the aneurysm to fill it. This blocks blood flow into the aneurysm and causes blood to clot.
  • Surgical removal of a tangle of thin-walled blood vessels, known as an AVM. Surgeons may remove a smaller AVM if it's in an area of the brain that's easy to access. This removes the risk of rupture and lowers the risk of hemorrhagic stroke. However, it's not always possible to remove an AVM if it's deep within the brain or if it's large. It also may not be possible to remove if the procedure would impact brain function.
  • Stereotactic radiosurgery. This procedure uses multiple beams of highly focused radiation to repair blood vessel malformations. Stereotactic radiosurgery is an advanced treatment that's not as invasive as other procedures.

Stroke recovery and rehabilitation

After emergency treatment, you're closely monitored for at least a day. After that, stroke care focuses on helping you recover as much function as possible and to return to independent living. The impact of the stroke depends on the area of the brain involved and the amount of tissue damaged.

If the stroke affected the right side of the brain, movement and feeling on the left side of your body may be affected. If the stroke damaged the left side of the brain, movement and feeling on the right side of your body may be affected. Brain damage to the left side of the brain also may cause speech and language disorders.

Most people who have had a stroke go to a rehabilitation program. Your healthcare professional can recommend the therapy program that is right for you. A program is recommended based on your age, overall health and degree of disability from the stroke. Your lifestyle, interests, priorities and whether you have help from family members or caregivers are considered.

Rehabilitation may begin before you leave the hospital. After discharge, you might continue the program in a rehabilitation unit of the same hospital. Or you may go to another rehabilitation unit or to a skilled nursing facility as an outpatient. You also might have rehabilitation at home.

Every person's stroke recovery is different. Depending on your condition, your treatment team may include:

  • Doctor trained in brain conditions, known as a neurologist.
  • Rehabilitation doctor, known as a physiatrist.
  • Rehabilitation nurse.
  • Dietitian.
  • Physical therapist.
  • Occupational therapist.
  • Recreational therapist.
  • Speech pathologist.
  • Social worker or case manager.
  • Psychologist or psychiatrist.
  • Chaplain.
Brain hemisphere connections

Coping and support

A stroke is a life-changing event that can affect your emotional well-being as much as your physical function. Some people may feel frustrated or depressed. A stroke may cause mood changes and a lower sex drive.

Maintaining your self-esteem, connections to others and interest in the world are essential parts of your recovery. Several strategies may help you and your caregivers, including:

  • Don't be hard on yourself. Physical and emotional recovery involves tough work and takes time. Celebrate your progress. Allow time for rest.
  • Join a support group. Meeting with others recovering from a stroke lets you get out and share experiences. You also can exchange information and build new friendships.
  • Let friends and family know what you need. People may want to help, but they may not know what to do. Let them know how they can help. You might ask that they bring over a meal and stay to eat with you and talk. Or you might ask that they attend social events or religious activities with you.

Communication challenges

Speech and language can be hard after a stroke. Here are some tips to help you and your caregivers cope with communication challenges:

  • Practice. Try to have a conversation at least once a day. It can help you learn what works best for you. It also can help you feel connected and rebuild your confidence.
  • Relax and take your time. Talking may be easiest and most enjoyable in a relaxing situation when you're not rushed. Some people who have had a stroke find that after dinner is a good time for conversation.
  • Say it your way. When you're recovering from a stroke, you may need to use fewer words. Rely on gestures or use your tone of voice to communicate.
  • Use props and communication aids. You may find it helpful to use cue cards to communicate. Cue cards might include words used often. Or they might include pictures of close friends and family members, a favorite television show, the bathroom, or other wants and needs.

Preparing for an appointment

A stroke in progress is usually diagnosed in a hospital. If you're having a stroke, your immediate care focuses on reducing brain damage. If you haven't had a stroke but you're worried about your risk, talk to your healthcare professional at your next appointment.

What to expect from your doctor

In the emergency room, you may see an emergency medicine specialist or a doctor trained in brain conditions, known as a neurologist. Nurses and medical technicians also are likely to be involved in your care.

Your emergency team's first priority is to stabilize your symptoms and overall medical condition. Then the team determines if you're having a stroke. Healthcare professionals try to find the cause of the stroke to determine the proper treatment.

If you're seeking medical advice during a scheduled appointment, your healthcare professional considers your risk factors for stroke and heart disease. Your healthcare professional can offer advice on how to lower your risk. This may include lifestyle strategies, stopping smoking or not using illicit drugs. Your healthcare professional also may consider if you need medicines to control high blood pressure, cholesterol and other stroke risk factors.