Also Known As
Ischemic stroke
Hemorrhagic stroke
Transient ischemic attack (TIA)
Cerebrovascular accident (CVA)
This article was last reviewed on
This article waslast modified on November 27, 2020.
What is a stroke?

It is important that anyone with sudden onset of symptoms suggestive of a stroke or transient ischemic attack (TIA) seek medical attention as soon as possible.

Knowing the warning signs of a stroke may be the difference between recovery and disability. Use the letters in "F.A.S.T." to spot stroke signs and know when to call 9-1-1.

F: Face drooping
A: Arm weakness
S: Speech difficulty
T: Time to call 9-1-1

Stroke occurs when the blood supply to a part of the brain is suddenly blocked or slowed. If any part of the body, including the brain, is without blood i.e., oxygen, the cells in that area will be injured and possibly die. Cell injury and/or death in the affected area will affect the function of the body parts controlled by that area, leading to some degree of impairment. Brain cell death is permanent and can result in lifelong effects, depending on location and extent of the damage.

Strokes are the fifth leading cause of death in the U.S. Each year, about 795,000 Americans suffer a new or repeated stroke while more than 147,000 people die as a result of stoke. Over 60% of stroke deaths occur in women. Strokes are also associated with long-term disability among survivors. About 25% of those who survive their first stroke will have another within 5 years.

The main types of stroke include:

  1. Ischemic – caused by a blockage of arteries supplying blood to the brain. This type accounts for 87% of strokes. It can occur from a blood clot that has formed inside an artery in the brain, possibly narrowed by plaque, (thrombotic stroke) obstructing blood flow or from a blood clot that breaks off in a blood vessel somewhere else in the body, which then travels to the brain, blocking a vessel there (embolic stroke).
  2. Hemorrhagic – caused by rupture of a weakened blood vessel, resulting in bleeding in and around the brain. This type can be caused by aneurysm(s) or head injuries. An aneurysm is a weakening in the wall of the artery and is associated with congenital defects or high blood pressure (hypertension). Hemorrhagic strokes are the most severe type and are often fatal.
  3. Transient ischemic attack (TIA) "mini-stroke" – these are episodes of transient stroke-like findings without death of brain cells that can resolve within 24 hours but may have permanent effects. They are caused by a clot or blockage in the brain that dissolves on its own or becomes dislodged. A TIA is a risk factor for subsequent strokes.
Accordion Title
About Strokes
  • Risk Factors

    There are many risk factors for stroke. Examples include:

    • High blood pressure (hypertension)
    • Coronary artery disease (CAD) and other heart problems, including atrial fibrillation and other heart disease
    • Diabetes mellitus
    • High cholesterol
    • Age – nearly 75% of all strokes occur in people over the age of 65 and the risk of stroke more than doubles for each decade of life after age 55.
    • Family history of stroke
    • Race and ethnicity – African Americans and Hispanics have a higher risk of stroke and/or death than Caucasians, resulting from higher risks of hypertension, diabetes and obesity.
    • Sex - men have more strokes than women, although more women than men die from stroke.
    • History of previous TIA

    Additional risk factors include:

  • Signs and Symptoms

    Most strokes are preceded by one or more mini-strokes called transient ischemic attacks (TIAs) that should act as a warning to seek medical attention immediately.

    While symptoms of a stroke typically persist, symptoms of a TIA typically resolve on their own within a few hours. About 9% to 17% of patients who have a TIA will have a stroke within the following 90 days.

    The five most common signs and symptoms of a stroke or TIA are:

    • Sudden numbness, weakness, or paralysis of the face, arm, or leg, usually on one side of the body
    • Sudden loss of speech or trouble talking or understanding what is said
    • Sudden dizziness, loss of balance, coordination, or trouble walking
    • Sudden blurred vision or difficulty seeing in one or both eyes
    • Severe, unexplained headache
  • Tests

    Diagnosis of a stroke is currently based mostly on non-laboratory testing, a history, and physical with emphasis on neurologic findings in conjunction with imaging tests such as a CT scan or MRI of the brain to look for any injury as well as tests of abnormal electrical activity and blood flow in the brain.

    Researchers continue to try to find laboratory tests, such as stroke biomarkers, that could be used in stroke diagnosis, treatment, and management. Examples of possible biomarkers that could be helpful include Lp-PLA2, NT-proBNP, glial fibrillary acidic protein, S100b, neuron specific enolase, myelin basic protein, interleukin-6, and matrix metalloproteinases (MMPs). It may be that a panel of biomarkers would be most effective as a diagnostic or risk assessment tool. These tests are used mainly in research studies at present.

    The following laboratory tests may be ordered as part of the patient evaluation:

    Less commonly, one or more tests may be done in specific situations to identify conditions that contribute to risk of stroke. Some examples include:

  • Prevention

    There are steps you can take to help prevent a stroke. Lifestyle changes, a healthy diet, exercise, weight loss, if needed, and stopping smoking can all help lower your risk. Identifying and treating medical conditions that increase your risk can also help prevent a stroke. Examples include:

  • Treatment

    It is important that anyone with sudden onset of symptoms suggestive of a stroke or transient ischemic attack (TIA) seek medical attention as soon as possible.

    Knowing the warning signs of a stroke may be the difference between recovery and disability. Use the letters in "F.A.S.T." to spot stroke signs and know when to call 9-1-1.

    F: Face drooping
    A: Arm weakness
    S: Speech difficulty
    T: Time to call 9-1-1

    If you or someone near you is having a stroke, immediate action is necessary. Treatment of a stroke depends on the type:

    • Ischemic stroke—a drug called tissue plasminogen activator (tPA) – a "clot-buster" – can be given for ischemic stroke, ideally within 3 (and up to 4.5) hours of the start of symptoms, which may reduce the chances of long-term disability. Sometimes, a procedure called a mechanical thrombectomy is performed. A long, thin tube (catheter) is inserted through an artery in the groin to the brain, where the clot is located. A device called a stent retriever opens to physically remove the clot.
    • Hemorrhagic stroke—a catheter may be threaded through an artery in an arm or leg to the brain and a device is deposited to stop the bleeding. Surgical procedures may be recommended if you have had a hemorrhagic stroke to prevent known aneurysms from rupturing or to remove abnormal blood vessels.

    For those who have disabilities as a result of a stroke, such as weakness or paralysis on one side of the body and speech or memory problems, rehabilitation can be helpful.

View Sources

Sources Used in Current Review

(March 12, 2020) Stroke Statistics. Centers for Disease Control and Prevention. Available online at https://www.cdc.gov/stroke/statistics_maps.htm. Accessed on 10/15/20.

(January 31, 2020) Stroke Types. Centers for Disease Control and Prevention. Available online at https://www.cdc.gov/stroke/types_of_stroke.htm. Accessed on 10/18/20.

(December 2018) Thrombotic Stroke. Harvard Health Publishing. Available online at https://www.health.harvard.edu/a_to_z/thrombotic-stroke-a-to-z. Accessed on 10/18/20.

Know Stroke: Know the Signs. Act in Time. National Institute of Health. National Institute of Neurological Disorders and Stroke. Available online at https://www.stroke.nih.gov/. Accessed on 10/18/20.

(January 31, 2020) Stroke Family History. Centers for Disease Control and Prevention. Available online at https://www.cdc.gov/stroke/family_history.htm. Accessed on 10/18/20.

Know Stroke. About the Campaign. National Institute of Health. National Institute of Neurological Disorders and Stroke. Available online at https://www.stroke.nih.gov/. Accessed on 10/18/20.

(October 10, 2018) Stroke Factors Not Within Your Control. National Stroke Association. Available online at https://www.stroke.org/en/about-stroke/stroke-risk-factors/stroke-risk-factors-not-within-your-control. Accessed on 10/18/20.

(December 20, 2018) What is a TIA. National Stroke Association. Available online at https://www.stroke.org/en/about-stroke/types-of-stroke/tia-transient-ischemic-attack/what-is-a-tia. Accessed on 10/18/20.

(February 2, 2019) Medical Tests. LDH isoenzyme blood test. University of California San Francisco Health. Available online at https://www.ucsfhealth.org/medical-tests/003499. Accessed on 10/18/20.

(2015) Factor VIII levels are associated with ischemic stroke, stroke subtypes and neurological worsening. PubMed.gov. Available online at https://pubmed.ncbi.nlm.nih.gov/25557373/. Accessed on 10/18/20.

(October 12, 2020) Improvements in stroke treatment could save more lives. Medical Xpress. Available online at https://medicalxpress.com/news/2020-10-treatment.html. Accessed on 10/18/20.

Stroke Symptoms. National Stroke Association. Available online at https://www.stroke.org/en/about-stroke/stroke-symptoms. Accessed on 10/18/20.

Jickling, G and Sharp, F. Biomarker Panels in Ischemic Stroke. Stroke. 2015;46:915–920. Available online at https://www.ahajournals.org/doi/10.1161/STROKEAHA.114.005604. Accessed November 2020.

Jickling, G and Sharp, F. Blood Biomarkers of Ischemic Stroke. Neurotherapeutics. 2011 Jul; 8(3): 349–360. Published online 2011 Jun 14. doi: 10.1007/s13311-011-0050-4. Accessed November 2020.

Reynolds MA, Kirchick HJ, Dahlen JR, et al. Early biomarkers of stroke. Clin Chem 2003; 49:1733.

Sources Used in Previous Reviews

Thomas, Clayton L., Editor (1997). Taber's Cyclopedic Medical Dictionary. F.A. Davis Company, Philadelphia, PA [18th Edition].

Pagana, Kathleen D. & Pagana, Timothy J. (2001). Mosby's Diagnostic and Laboratory Test Reference 5th Edition: Mosby, Inc., Saint Louis, MO.

Klausner HA, Lewandowski C. Infrequent causes of stroke. Emerg Med Clinics of North Amer 20:657, 2002.

Chalel JA, Merino JG, Warach S. Update on stroke. Curr Opin Neurol 17:447, 2004.

Harrison's Principles of Internal Medicine, 16th Ed. Kasper DL, et al., Eds. McGraw-Hill Companies. 2005.

Christenson RH and Dambinova S. Stroke: A Look at Emerging Biochemical Markers. Clinical Laboratory News March 2008. Volume 34, Number 3. Available online at http://www.aacc.org/publications/cln/2008/mar/Pages/series_0308.aspx. Accessed May 2008.

The Internet Stroke Center: Blood Tests and Procedures Used for Stroke Diagnosis. Available online at http://www.strokecenter.org/pat/diagnosis/blood_tests.htm. Accessed May 2008.

National Institute of Neurological Disorders and Stroke. Stroke Information Page. Available online at http://www.ninds.nih.gov/disorders/stroke/stroke.htm. Accessed May 2008.

National Institute of Neurological Disorders and Stroke. Stroke Information Page. Available online at http://www.ninds.nih.gov/disorders/stroke/stroke.htm. Accessed September 2011.

American Stroke Association. Warning Signs. Available online at http://www.strokeassociation.org/STROKEORG/WarningSigns/Warning-Signs_UCM_308528_SubHomePage.jsp. Accessed September 2011.

American Stroke Association. Impact of Stroke. Available online at http://www.strokeassociation.org/STROKEORG/AboutStroke/Impact-of-Stroke_UCM_310728_Article.jsp. Accessed September 2011.

American Stroke Association. Understanding Risk. Available online at http://www.strokeassociation.org/STROKEORG/AboutStroke/UnderstandingRisk/Understanding-Risk_UCM_308539_SubHomePage.jsp. Accessed September 2011.

American Stroke Association. Diagnosis. Available online at http://www.strokeassociation.org/STROKEORG/AboutStroke/Diagnosis/Diagnosis_UCM_310890_Article.jsp. Accessed September 2011.

American Stroke Association. Treatment. Available online at http://www.strokeassociation.org/STROKEORG/AboutStroke/Treatment/Treatment_UCM_310892_Article.jsp. Accessed September 2011.

MedlinePlus Medical Encyclopedia. Stroke. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/000726.htm. Accessed September 2011.

Hijazi, Z et al. Abstract 13472: NT-proBNP is Prognostic for Stroke and Death in Atrial Fibrillation - a RELY Substudy. Circulation November 2010, 122 (Meeting Abstract Supplement). Available online at http://circ.ahajournals.org/cgi/content/meeting_abstract/122/21_MeetingAbstracts/A13472. Accessed September 2011.

Fonseca AC et al. N-terminal probrain natriuretic peptide as a biomarker of cardioembolic stroke.Int J Stroke 2011 Oct;6(5):398-403. doi: 10.1111/j.1747-4949.2011.00606.x. Epub 2011 Jun 6. Available online at http://www.ncbi.nlm.nih.gov/pubmed/21645267. Accessed September 2011.

Internet Stroke Center. Blood Tests. Available online at http://www.strokecenter.org/patients/stroke-diagnosis/blood-tests/. Accessed September 2011.

Jauch, E. and Stettler, B. (2015 Nov 23, Updated). Ischemic Stroke. Medscape Drugs and Diseases [On-line information]. Available online at http://emedicine.medscape.com/article/1916852-overview. Accessed March 2016.

Liebeskind, D. (2015 January 8, Updated). Hemorrhagic Stroke. Medscape Drugs and Diseases [On-line information]. Available online at http://emedicine.medscape.com/article/1916662-overview. Accessed March 2016.

(2014 December 17). Heart Disease and Stroke Statistics – At-a-Glance. American Health Association [On-line information]. Available online at http://www.heart.org/idc/groups/ahamah-public/@wcm/@sop/@smd/documents/downloadable/ucm_470704.pdf. Accessed March 2016.

(2015 October 28, Updated). What Is a Stroke? National Heart Lung and Blood Institute [On-line information]. Available online at http://www.nhlbi.nih.gov/health/health-topics/topics/stroke. Accessed on March 2016.

(2015 October 18, Modified). NINDS Stroke Information Page. National Institute of Neurological Disorders and Stroke. [On-line information]. Available online at http://www.ninds.nih.gov/disorders/stroke/stroke.htm. Accessed March 2016.

Mayo Clinic Staff. (© 1998-2016).Stroke Symptoms and Causes. Mayo Clinic [On-line information]. Available online at http://www.mayoclinic.org/diseases-conditions/stroke/symptoms-causes/dxc-20117265?p=1. Accessed March 2016.

Giraldo, E. (2013 November, Revised). Overview of Stroke. Merck Manual Professional Version [On-line information]. Available online at http://www.merckmanuals.com/professional/neurologic-disorders/stroke-cva/overview-of-stroke. Accessed March 2016.