Stroke
Overview
An ischemic stroke occurs when the blood supply to part of the brain is interrupted or reduced, preventing brain tissue from getting oxygen and nutrients. Brain cells begin to die in minutes.
A stroke is a medical emergency, and prompt treatment is crucial. Early action can reduce brain damage and other complications.
The good news is that many fewer Americans die of stroke now than in the past. Effective treatments can also help prevent disability from stroke.
Symptoms
If you or someone you're with may be having a stroke, pay particular attention to the time the symptoms began. Some treatment options are most effective when given soon after a stroke begins.
Signs and symptoms of stroke include:
- Trouble speaking and understanding what others are saying. You may experience confusion, slur words or have difficulty understanding speech.
- Paralysis or numbness of the face, arm or leg. You may develop sudden numbness, weakness or paralysis in the face, arm or leg. This often affects just one side of the body. Try to raise both your arms over your head at the same time. If one arm begins to fall, you may be having a stroke. Also, one side of your mouth may droop when you try to smile.
- Problems seeing in one or both eyes. You may suddenly have blurred or blackened vision in one or both eyes, or you may see double.
- Headache. A sudden, severe headache, which may be accompanied by vomiting, dizziness or altered consciousness, may indicate that you're having a stroke.
- Trouble walking. You may stumble or lose your balance. You may also have sudden dizziness or a loss of coordination.
When to see a doctor
Seek immediate medical attention if you notice any signs or 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 his or her speech slurred or strange?
- Time. If you observe any of these signs, call 911 or emergency medical help immediately.
Call 911 or your local emergency number right away. 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: a blocked artery (ischemic stroke) or leaking or bursting of a blood vessel (hemorrhagic stroke). Some people may have only a temporary disruption of blood flow to the brain, known as a transient ischemic attack (TIA), that 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, causing severely reduced blood flow (ischemia). Blocked or narrowed blood vessels are caused by fatty deposits that build up in blood vessels or by blood clots or other debris that travel through the bloodstream, most often from the heart, and lodge in the blood vessels in the brain.
Some initial 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. Brain hemorrhages can result from many conditions that affect the blood vessels. Factors related to hemorrhagic stroke include:
- Uncontrolled high blood pressure
- Overtreatment with blood thinners (anticoagulants)
- Bulges at weak spots in your blood vessel walls (aneurysms)
- Trauma (such as a car accident)
- Protein deposits in blood vessel walls that lead to weakness in the vessel wall (cerebral amyloid angiopathy)
- Ischemic stroke leading to hemorrhage
A less common cause of bleeding in the brain is the rupture of an irregular tangle of thin-walled blood vessels (arteriovenous malformation).
Transient ischemic attack (TIA)
A transient ischemic attack (TIA) — sometimes known as a ministroke — is a temporary period of symptoms similar to those in a stroke. A TIA doesn't cause permanent damage. A TIA is caused by a temporary decrease in blood supply to part of the brain, which may last as little as five minutes.
Like an ischemic stroke, a TIA occurs when a clot or debris reduces or blocks blood flow to part of the nervous system.
Seek emergency care even if you think you've had a TIA because your symptoms got better. 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 full-blown stroke later.
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 Americans and Hispanics 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 — Use of birth control pills or hormone therapies that include estrogen increases risk.
Complications
A stroke can sometimes cause temporary or permanent disabilities, depending on how long the brain lacks blood flow and which part is affected. Complications may include:
- Paralysis or loss of muscle movement. You may become paralyzed on one side of the body, or lose control of certain muscles, such as those on one side of the face or one arm.
- Difficulty talking or swallowing. A stroke might affect control of the muscles in the mouth and throat, making it difficult for you to talk clearly, swallow or eat. You also may have difficulty with language, including speaking or understanding speech, reading, or writing.
- Memory loss or thinking difficulties. Many people who have had strokes experience some memory loss. Others may have difficulty thinking, reasoning, making judgments and understanding concepts.
- Emotional problems. People who have had strokes may have more difficulty controlling their emotions, or they may develop depression.
- Pain. Pain, numbness or other unusual sensations may occur in the parts of the body affected by stroke. For example, if a stroke causes you to lose feeling in the left arm, you may develop an uncomfortable tingling sensation in that arm.
- Changes in behavior and self-care ability. People who have had strokes may become more withdrawn. They may need help with grooming and daily chores.
Prevention
Knowing your stroke risk factors, following your health care provider's recommendations and adopting a healthy lifestyle are the best steps you can take to prevent a stroke. If you've had a stroke or a transient ischemic attack (TIA), these measures might help prevent another 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:
- Controlling high blood pressure (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 subsequent TIA or stroke. Healthy lifestyle changes and medications are often used to treat high blood pressure.
- Lowering the amount of cholesterol and saturated fat in your diet. Eating less cholesterol and fat, especially saturated fat and trans fats, may reduce buildup in the arteries. If you can't control your cholesterol through dietary changes alone, your doctor may prescribe a cholesterol-lowering medication.
- Quitting tobacco use. Smoking raises the risk of stroke for smokers and nonsmokers exposed to secondhand smoke. Quitting tobacco use reduces the risk of stroke.
- Managing diabetes. Diet, exercise and losing weight can help you keep your blood sugar in a healthy range. If lifestyle factors don't seem to be enough to control your diabetes, your doctor may prescribe diabetes medication.
- Maintaining a healthy weight. Being overweight contributes to other stroke risk factors, such as high blood pressure, cardiovascular disease and diabetes.
- Eating a diet rich in fruits and vegetables. A diet containing five or more daily servings of fruits or vegetables may reduce the risk of stroke. The Mediterranean diet, which emphasizes olive oil, fruit, nuts, vegetables and whole grains, may be helpful.
- Exercising 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 — such as walking, jogging, swimming or bicycling — on most, if not all, days of the week.
- Drinking alcohol in moderation, if at all. Heavy alcohol consumption increases the risk of high blood pressure, ischemic strokes and hemorrhagic strokes. Alcohol may also interact with other drugs you're taking. However, drinking small to moderate amounts of alcohol, such as one drink a day, may help prevent ischemic stroke and decrease the blood's clotting tendency. Talk to your doctor about what's appropriate for you.
- Treating obstructive sleep apnea (OSA). Your doctor may recommend a sleep study if you have symptoms of OSA — a sleep disorder that causes you to stop breathing for short periods repeatedly during sleep. Treatment for OSA includes a device that delivers positive airway pressure through a mask to keep the airway open while you sleep.
- Avoiding illegal drugs. Certain street drugs, such as cocaine and methamphetamine, are established risk factors for a TIA or a stroke.
Preventive medications
If you've had an ischemic stroke or a TIA, your doctor may recommend medications to help reduce your risk of having another stroke. These include:
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Anti-platelet drugs. Platelets are cells in the blood that form clots. Anti-platelet drugs make these cells less sticky and less likely to clot. The most commonly used anti-platelet medication is aspirin. Your doctor can help you determine the right dose of aspirin for you.
After a TIA or minor stroke, your doctor may give you aspirin and an anti-platelet drug such as clopidogrel (Plavix) for a period of time to reduce the risk of another stroke. If you can't take aspirin, your doctor may prescribe clopidogrel alone.
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Anticoagulants. These drugs reduce blood clotting. Heparin is fast acting and 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 drug, so you'll need to take it exactly as directed and watch for side effects. You'll also need to have regular blood tests to monitor warfarin's effects.
Several newer blood-thinning medications (anticoagulants) are available for preventing strokes in people who have a high risk. These medications include dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis) and edoxaban (Savaysa). They're shorter acting than warfarin and usually don't require regular blood tests or monitoring by your doctor. These drugs are also associated with a lower risk of bleeding complications compared to warfarin.
Diagnosis
Things will move quickly once you get to the hospital, as your emergency team tries to determine what type of stroke you're having. That means you'll have a CT scan or other imaging test soon after arrival. Doctors 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. Your doctor will do a number of tests you're familiar with, such as listening to the heart and checking the blood pressure. You'll also have a neurological exam to see how a potential stroke is affecting your nervous system.
- Blood tests. You may have several blood tests, including tests to check how fast the blood clots, whether the blood sugar is too high or low, and whether 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. Doctors may inject a dye into your bloodstream to view the blood vessels in the neck and brain in greater detail (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. An MRI can detect brain tissue damaged by an ischemic stroke and brain hemorrhages. Your doctor may inject a dye into a blood vessel to view the arteries and veins and highlight blood flow (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. This test shows buildup of fatty deposits (plaques) and blood flow in the carotid arteries.
- Cerebral angiogram. In this uncommonly used test, your doctor inserts a thin, flexible tube (catheter) through a small incision, usually in the groin, and guides it through the major arteries and into the carotid or vertebral artery. Then your doctor injects a dye into the blood vessels to make them visible under X-ray imaging. This procedure gives a detailed view of arteries in the brain and neck.
- 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 from the heart to the brain and caused a stroke.
Treatment
Emergency treatment for stroke depends on whether you're having an ischemic stroke or a stroke that involves bleeding into the brain (hemorrhagic).
Ischemic stroke
To treat an ischemic stroke, doctors must quickly restore blood flow to the brain. This may be done with:
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Emergency IV medication. Therapy with drugs that can break up a clot has to be given within 4.5 hours from when symptoms first started if given intravenously. The sooner these drugs are given, the better. Quick treatment not only improves your chances of survival but also may reduce complications.
An IV injection of recombinant tissue plasminogen activator (TPA) — also called alteplase (Activase) or tenecteplase (TNKase) — is the gold standard treatment for ischemic stroke. 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 drug 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 doctor will consider certain risks, such as potential bleeding in the brain, to determine whether TPA is appropriate for you.
- Emergency endovascular procedures. Doctors sometimes treat ischemic strokes directly inside the blocked blood vessel. Endovascular therapy has been shown to significantly improve outcomes and reduce long-term disability after ischemic stroke. These procedures must be performed as soon as possible:
- Medications delivered directly to the brain. Doctors insert a long, thin tube (catheter) through an artery in the groin and thread it 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. Doctors can use a device attached to a catheter to directly remove the clot from the blocked blood vessel in the brain. This procedure is particularly beneficial for people with large clots that can't be completely dissolved with TPA. This procedure is often performed in combination with injected TPA.
The time window when these procedures can be considered has been expanding due to newer imaging technology. Doctors may order perfusion imaging tests (done with CT or MRI) to help determine how likely it is that someone can benefit from endovascular therapy.
Other procedures
To decrease your risk of having another stroke or transient ischemic attack, your doctor may recommend a procedure to open up an artery that's narrowed by plaque. Options vary depending on the situation, but include:
- Carotid endarterectomy. Carotid arteries are the blood vessels that run along each side of the neck, supplying the brain (carotid arteries) 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 the excess fluid. Treatment options include:
- Emergency measures. If you take blood-thinning medications to prevent blood clots, you may be given drugs or transfusions of blood products to counteract the blood thinners' effects. You may also be given drugs to lower the pressure in the brain (intracranial pressure), lower blood pressure, prevent spasms of the blood vessels and prevent seizures.
- Surgery. If the area of bleeding is large, your doctor may perform surgery to remove the blood and relieve pressure on the brain. Surgery may also be used to repair blood vessel problems associated with hemorrhagic strokes. Your doctor may recommend one of these procedures after a stroke or if an aneurysm, arteriovenous malformation (AVM) or other type of blood vessel problem caused the hemorrhagic stroke.
- Surgical clipping. A surgeon places a tiny clamp at the base of the aneurysm to stop blood flow to it. This clamp can keep the aneurysm from bursting, or it can keep an aneurysm that has recently hemorrhaged from bleeding again.
- Coiling (endovascular embolization). Using a catheter inserted into an artery in the groin and guided to the brain, the surgeon will place tiny detachable coils into the aneurysm to fill it. This blocks blood flow into the aneurysm and causes blood to clot.
- Surgical AVM removal. Surgeons may remove a smaller AVM if it's located in an accessible area of the brain. This eliminates the risk of rupture and lowers the risk of hemorrhagic stroke. However, it's not always possible to remove an AVM if it's located deep within the brain, it's large, or its removal would cause too much of an impact on brain function.
- Stereotactic radiosurgery. Using multiple beams of highly focused radiation, stereotactic radiosurgery is an advanced minimally invasive treatment used to repair blood vessel malformations.
Stroke recovery and rehabilitation
After emergency treatment, you'll be closely monitored for at least a day. After that, stroke care focuses on helping you recover as much function as possible and 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, your movement and sensation on the left side of the body may be affected. If the stroke damaged the brain tissue on the left side of the brain, your movement and sensation on the right side of the body may be affected. Brain damage to the left side of the brain may cause speech and language disorders.
Most stroke survivors go to a rehabilitation program. Your doctor will recommend the most rigorous therapy program you can handle based on your age, overall health and degree of disability from the stroke. Your doctor will take into consideration your lifestyle, interests and priorities, and the availability of family members or other caregivers.
Rehabilitation may begin before you leave the hospital. After discharge, you might continue your program in a rehabilitation unit of the same hospital, another rehabilitation unit or skilled nursing facility, as an outpatient, or at home.
Every person's stroke recovery is different. Depending on your condition, your treatment team may include:
- Doctor trained in brain conditions (neurologist)
- Rehabilitation doctor (physiatrist)
- Rehabilitation nurse
- Dietitian
- Physical therapist
- Occupational therapist
- Recreational therapist
- Speech pathologist
- Social worker or case manager
- Psychologist or psychiatrist
- Chaplain
Treatment outcomes
One way to evaluate the care of patients diagnosed with stroke is to look at the percentage of patients receiving the timely and effective care measures that are appropriate.
The graphs below display the percentage of eligible Mayo Clinic patients diagnosed with stroke receiving all of the appropriate care measures.
Stroke Core Measure
Carotid Endarterectomy Mortality
Carotid Stenting Mortality
Comprehensive Stroke Measure
Comprehensive Stroke – Arrival Time to Skin Puncture
Comprehensive Stroke – Post Thrombolysis Revascularization Rate
Comprehensive Stroke – Timeliness of IV t-PA Therapy
For additional information and data visit Medicare Hospital Compare.
For additional information about quality at Mayo Clinic visit Quality Measures.
Clinical trials
Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.
Coping and support
A stroke is a life-changing event that can affect your emotional well-being as much as your physical function. You may sometimes feel helpless, frustrated, depressed and apathetic. You may also have 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. Accept that physical and emotional recovery will involve tough work and that it will take time. Aim for a "new normal," and celebrate your progress. Allow time for rest.
- Join a support group. Meeting with others who are coping with a stroke lets you get out and share experiences, 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, such as by bringing over a meal and staying to eat with you and talk, or attending social events or religious activities with you.
Communication challenges
Problems with speech and language can be especially frustrating. 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 will help you learn what works best for you. It will also help you feel connected and help 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 stroke survivors find that after dinner is a good time.
- 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 showing frequently used words or pictures of close friends and family members, a favorite television show, the bathroom, or other regular wants and needs.
Preparing for your appointment
A stroke in progress is usually diagnosed in a hospital. If you're having a stroke, your immediate care will focus on minimizing brain damage. If you haven't yet had a stroke but you're worried about your future risk, you can discuss your concerns with your doctor at your next scheduled 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 (neurologist), as well as nurses and medical technicians.
Your emergency team's first priority will be to stabilize your symptoms and overall medical condition. Then the team will determine if you're having a stroke. Doctors will try to find the cause of the stroke to determine the most appropriate treatment.
If you're seeking your doctor's advice during a scheduled appointment, your doctor will evaluate your risk factors for stroke and heart disease. Your discussion will focus on avoiding these risk factors, such as not smoking or using illegal drugs. Your doctor will also discuss lifestyle strategies or medications to control high blood pressure, cholesterol and other stroke risk factors.