What is a stroke?
A stroke happens when there is a loss of blood flow to part of the brain. Your brain cells cannot get the oxygen and nutrients they need from blood, and they start to die within a few minutes. This can cause lasting brain damage, long-term disability, or even death.
If you think that you or someone else is having a stroke, call 911 right away. Immediate treatment may save someone's life and increase the chances for successful rehabilitation and recovery.
What are the types of stroke?
There are two types of stroke:
- Ischemic stroke is caused by a blood clot that blocks or plugs a blood vessel in the brain. This is the most common type; about 80% of strokes are ischemic.
- Hemorrhagic stroke is caused by a blood vessel that breaks and bleeds into the brain
Another condition that's similar to a stroke is a transient ischemic attack (TIA). It's sometimes called a "mini-stroke." TIAs happen when the blood supply to the brain is blocked for a short time. The damage to the brain cells isn't permanent, but if you have had a TIA, you are at a much higher risk of having a stroke.
Who is at risk for a stroke?
Certain factors can raise your risk of a stroke. The major risk factors include:
- High blood pressure. This is the primary risk factor for a stroke.
- Heart diseases. Atrial fibrillation and other heart diseases can cause blood clots that lead to stroke.
- Smoking. When you smoke, you damage your blood vessels and raise your blood pressure.
- A personal or family history of stroke or TIA.
- Age. Your risk of stroke increases as you get older.
- Race and ethnicity. African Americans have a higher risk of stroke.
There are also other factors that are linked to a higher risk of stroke, such as:
- Alcohol and illegal drug use
- Not getting enough physical activity
- High cholesterol
- Unhealthy diet
- Having obesity
What are the symptoms of stroke?
The symptoms of stroke often happen quickly. They include:
- Sudden numbness or weakness of the face, arm, or leg (especially on one side of the body)
- Sudden confusion, trouble speaking, or understanding speech
- Sudden trouble seeing in one or both eyes
- Sudden difficulty walking, dizziness, loss of balance or coordination
- Sudden severe headache with no known cause
If you think that you or someone else is having a stroke, call 911 right away.
How are strokes diagnosed?
To make a diagnosis, your health care provider will:
- Ask about your symptoms and medical history
- Do a physical exam, including a check of
- Your mental alertness
- Your coordination and balance
- Any numbness or weakness in your face, arms, and legs
- Any trouble speaking and seeing clearly
- Run some tests, which may include
- Diagnostic imaging of the brain, such as a CT scan or MRI
- Heart tests, which can help detect heart problems or blood clots that may have led to a stroke. Possible tests include an electrocardiogram (EKG) and an echocardiography.
What are the treatments for stroke?
Treatments for stroke include medicines, surgery, and rehabilitation. Which treatments you get depend on the type of stroke and the stage of treatment. The different stages are:
- Acute treatment, to try to stop a stroke while it is happening
- Post-stroke rehabilitation, to overcome the disabilities caused by the stroke
- Prevention, to prevent a first stroke or, if you have already had one, prevent another stroke
Acute treatments for ischemic stroke are usually medicines:
- You may get tPA, (tissue plasminogen activator), a medicine to dissolve the blood clot. You can only get this medicine within 4 hours of when your symptoms started. The sooner you can get it, the better your chance of recovery.
- If you cannot get that medicine, you may get medicine that helps stop platelets from clumping together to form blood clots. Or you may get a blood thinner to keep existing clots from getting bigger.
- If you have carotid artery disease, you may also need a procedure to open your blocked carotid artery
Acute treatments for hemorrhagic stroke focus on stopping the bleeding. The first step is to find the cause of bleeding in the brain. The next step is to control it:
- If high blood pressure is the cause of bleeding, you may be given blood pressure medicines.
- If an aneurysm if the cause, you may need aneurysm clipping or coil embolization. These are surgeries to prevent further leaking of blood from the aneurysm. It also can help prevent the aneurysm from bursting again.
- If an arteriovenous malformation (AVM) is the cause of a stroke, you may need an AVM repair. An AVM is a tangle of faulty arteries and veins that can rupture within the brain. An AVM repair may be done through
- Injecting a substance into the blood vessels of the AVM to block blood flow
- Radiation to shrink the blood vessels of the AVM
Stroke rehabilitation can help you relearn skills you lost because of the damage. The goal is to help you become as independent as possible and to have the best possible quality of life.
Prevention of another stroke is also important, since having a stroke increases the risk of getting another one. Prevention may include heart-healthy lifestyle changes and medicines.
Can strokes be prevented?
If you have already had a stroke or are at risk of having a stroke, you can make some heart-healthy lifestyle changes to try to prevent a future stroke:
- Eating a heart-healthy diet
- Aiming for a healthy weight
- Managing stress
- Getting regular physical activity
- Quitting smoking
- Managing your blood pressure and cholesterol levels
If these changes aren't enough, you may need medicine to control your risk factors.
NIH: National Institute of Neurological Disorders and Stroke
- Know Stroke. Know the Signs. Act in Time. (National Institute of Neurological Disorders and Stroke)
- Stroke (National Institute of Neurological Disorders and Stroke) Also in Spanish
- Types of Stroke and Treatment (American Stroke Association)
- What Is a Stroke? (National Heart, Lung, and Blood Institute)
- Stroke Risk Factors and Symptoms (National Institute of Neurological Disorders and Stroke)
Diagnosis and Tests
- Carotid Ultrasound Imaging (American College of Radiology; Radiological Society of North America) Also in Spanish
- Catheter Angiography (American College of Radiology; Radiological Society of North America) Also in Spanish
- Cranial Ultrasound (American College of Radiology; Radiological Society of North America) Also in Spanish
- CT Perfusion of the Head (American College of Radiology; Radiological Society of North America) Also in Spanish
- Lipoprotein (a) Blood Test (National Library of Medicine) Also in Spanish
- Magnetic Resonance, Functional (fMRI) -- Brain (American College of Radiology; Radiological Society of North America) Also in Spanish
- What Are the Warning Signs of Stroke? (American Heart Association) - PDF
Prevention and Risk Factors
- Before Using Aspirin to Lower Your Risk of Heart Attack or Stroke, Here Is What You Should Know (Food and Drug Administration)
- Brain Basics: Preventing Stroke (National Institute of Neurological Disorders and Stroke)
- Let's Talk about Lifestyle Changes to Prevent Stroke (American Stroke Association) - PDF
- Mind Your Risks (National Institute of Neurological Disorders and Stroke)
- Prevent Stroke: What You Can Do (Centers for Disease Control and Prevention)
Treatments and Therapies
- Stroke: First Aid (Mayo Foundation for Medical Education and Research) Also in Spanish
- Treat and Recover from Stroke (Centers for Disease Control and Prevention)
- What Are Some Common Outcomes of Stroke and Some Common Treatments for These Outcomes? (Eunice Kennedy Shriver National Institute of Child Health and Human Development) Also in Spanish
- Agnosia (National Institute of Neurological Disorders and Stroke)
- Atherosclerosis and Stroke (American Stroke Association)
- Diabetes, Heart Disease, and Stroke (National Institute of Diabetes and Digestive and Kidney Diseases) Also in Spanish
- Heart Disease, Stroke, or Other Cardiovascular Disease and Adult Vaccination (Centers for Disease Control and Prevention) Also in Spanish
- High Blood Pressure, Afib and Your Risk of Stroke (American Heart Association)
- Strokes May Lead to Epilepsy (Centers for Disease Control and Prevention)
- Hemorrhagic Stroke: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish
- Ischemic Stroke: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish
- Spinal Cord Infarction (National Institute of Neurological Disorders and Stroke)
- Wallenberg's Syndrome (National Institute of Neurological Disorders and Stroke)
- Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy: MedlinePlus Genetics (National Library of Medicine)
- Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes: MedlinePlus Genetics (National Library of Medicine)
- Craniotomy - slideshow (Medical Encyclopedia) Also in Spanish
- Test Your Stroke Knowledge (National Institute of Neurological Disorders and Stroke)
Statistics and Research
- FastStats: Cerebrovascular Disease or Stroke (National Center for Health Statistics)
- Heart Disease and Stroke Statistics (American Heart Association)
- Interactive Atlas of Heart Disease and Stroke (Centers for Disease Control and Prevention)
- Preventing Stroke Deaths (Centers for Disease Control and Prevention)
- Stroke Facts and Statistics (Centers for Disease Control and Prevention)
- ClinicalTrials.gov: Carotid Stenosis (National Institutes of Health)
- ClinicalTrials.gov: Endarterectomy, Carotid (National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Association of CYP2C19 Loss-of-Function Metabolizer Status With Stroke Risk Among Chinese...
- Article: Effect of Cathodal Transcranial Direct Current Stimulation for Lower Limb Subacute...
- Article: Effectiveness of a Quality Improvement Intervention on Reperfusion Treatment for Patients...
- Stroke -- see more articles
- Stroke Connection e-news (American Stroke Association)
Find an Expert
- American Heart Association
- American Stroke Association
- Find a Physical Medicine & Rehabilitation Physician (American Academy of Physical Medicine and Rehabilitation)
- National Institute of Neurological Disorders and Stroke Also in Spanish
- Heart Disease and Stroke (Department of Health and Human Services, Office on Women's Health)
- What Every Woman Needs to Know about Stroke (Department of Health and Human Services, Office on Women's Health) Also in Spanish
- Women Have a Higher Risk of Stroke (American Stroke Association)
- Stroke: Unique to Older Adults (AGS Health in Aging Foundation)
- EEG (Medical Encyclopedia) Also in Spanish
- Preventing stroke (Medical Encyclopedia) Also in Spanish
- Stroke (Medical Encyclopedia) Also in Spanish
- Stroke - discharge (Medical Encyclopedia) Also in Spanish