(Stroke, Left-side; Left Hemisphere Stroke; Stroke, Left Hemisphere)
The cerebrum, the largest part of the brain, is separated into the right and left hemispheres. The left hemisphere is in charge of the functions on the right-side of the body, as well as the ability to speak, use language, and other abilities.
A left-side stroke happens when the brain’s blood supply is interrupted in this area. Without oxygen and nutrients from blood, the brain tissue quickly dies. A stroke is a serious condition. It requires emergency care.
© 2011 Nucleus Medical Media, Inc.
There are two main types of stroke:
An ischemic stroke (the more common form) is caused by a sudden decrease in blood flow to a region of the brain, which may be due to:
- A clot that forms in another part of the body (eg, heart or neck) breaking off and blocking the flow in a blood vessel supplying the brain (embolus).
- A clot that forms in an artery that supplies blood to the brain (thrombus)
- A tear in a blood vessel supplying a part of the brain (arterial dissection)
A hemorrhagic stroke is caused by a burst blood vessel that results in bleeding in the brain.
Hemorrhagic vs. Ischemic Stroke
© 2011 Nucleus Medical Media, Inc.
Examples of risk factors that you can control or treat include:
- Certain conditions, like:
- Medicines (eg, long-term use of birth control pills)
- Lifestyle factors
- Physical inactivity
- Diet high in sodium and processed foods
Risk factors that you cannot control include:
- History of stroke, heart attack, or other type of cardiovascular disease
- History of transient ischemic attack (TIA)—With a TIA, stroke symptoms often resolve within minutes (and always within 24 hours). They may signal a very high risk of having a stroke in the future.
- Age: 60 or older
- Family members who have had a stroke
- Gender: males
- Race: Black, Asian, Hispanic
- Blood disorder that increases clotting
- Heart valve disease (eg, mitral stenosis)
The immediate symptoms of a left-side stroke come on suddenly and may include:
- Weakness or numbness of face, arm, or leg, especially on the right side of the body
- Trouble speaking or understanding (aphasia)
- Dizziness, loss of balance
- Vision problems (on the right side of vision in both eyes)
- Difficulty swallowing
If you or someone you know has any of these symptoms, call 911 right away. A stroke needs to be treated as soon as possible.
Longer-lasting effects of the stroke may include problems with:
- Movement on the right-side of the body
- Speaking, understanding language, reading, and writing
- Organizing, analyzing, reasoning, planning
- Memory and learning
- Completing tasks (difficulty doing activities, difficulty planning)
- Short attention span
- Vision (difficulty seeing out of the right field of vision)
- Mental health (eg, depression, cautiousness, compulsive behavior, lack of motivation, frustration)
The doctor will make a diagnosis as quickly as possible. Tests may include:
- Exam of nervous system
- Computed tomography (CT) scan—a type of x-ray that uses a computer to make pictures of the brain
- CT angiogram—a type of CT scan that evaluates the blood vessels in the brain and/or neck
- Magnetic resonance imaging (MRI)—a test that uses magnetic waves to make pictures of the brain
- Magnetic resonance angiography (MRA)—a type of MRI scan that evaluates the blood vessels in the brain and/or neck
- Heart function tests (eg, electrocardiogram, echocardiogram)
- Doppler ultrasound—a test that uses sound waves to examine blood vessels
- Blood tests
- Tests to check the level of oxygen in the blood
- Kidney and liver function tests
- Tests to evaluate the ability to swallow
Immediate treatment is needed to:
- Dissolve a clot causing an ischemic stroke
- Stop the bleeding during a hemorrhagic stroke
In some cases, oxygen therapy is needed.
Medicines may be given right away for an ischemic stroke to:
- Dissolve clots and prevent new ones from forming
- Thin blood
- Control blood pressure
- Reduce brain swelling
- Treat an irregular heart rate
For a hemorrhagic stroke, the doctor may give medicines to:
- Work against any blood-thinning drugs that you may regularly take
- Reduce how your brain reacts to bleeding
- Control blood pressure
- Prevent seizures
For an ischemic stroke, procedures may be done to:
- Reroute blood supply around a blocked artery
- Remove the clot or deliver clot-dissolving medicine
- Remove fatty deposits from a carotid artery (major arteries in the neck that lead to the brain)
- Widen carotid artery and add a mesh tube to keep it open (eg, carotid angioplasty or stenting)
For a hemorrhagic stroke, the doctor may:
- Remove a piece of the skull to relieve pressure on the brain and remove the blood clot
- Place a clip or tiny coil in the aneurysm to stop it from bleeding
A rehabilitation program focuses on:
- Physical therapy—to regain as much movement as possible
- Occupational therapy—to assist in everyday tasks and self-care
- Speech therapy—to improve swallowing and speech challenges
- Psychological therapy—to help adjust to life after the stroke
To help reduce your chance of having a stroke, take the following steps:
- Exercise regularly.
- Eat a healthy diet that includes fruits, vegetables, whole grains, and fish.
- Maintain a healthy weight.
- Drink alcohol only in moderation (1-2 drinks per day).
- If you smoke, quit.
- If you have a chronic condition, like high blood pressure or diabetes, get proper treatment.
- If recommended by your doctor, take a low-dose aspirin every day.
- If you are at risk for having a stroke, talk to your doctor about statin medicines.
American Heart Association
National Stroke Association
Heart and Stroke Foundation of Canada
Association of Ottawa
Am I at risk for a stroke? National Stroke Association website. Available at: http://www.stroke.org/site/PageServer?pagename=risk. Accessed April 22, 2011.
Anatomy of the brain. The University Hospital website. Available at: http://www.theuniversityhospital.com/stroke/anatomy.htm. Accessed April 22, 2011.
Effects of left middle cerebral artery stroke. Ohio State University Medical Center website. Available at: http://medicalcenter.osu.edu/PatientEd/Materials/PDFDocs/dis-cond/stroke/LeftMidCerebralArteryStroke.pdf. Accessed April 15, 2011.
Effects of stroke. Magee Rehabilitation website. Available at: http://www.mageerehab.org/effects-of-stroke.php. Accessed April 22, 2011.
Effects of stroke. National Stroke Association website. Available at: http://www.stroke.org/site/PageServer?pagename=EFFECT. Accessed April 22, 2011.
Effects of stroke. Ohio State University Medical Center website. Available at: http://medicalcenter.osu.edu/patientcare/healthcare_services/stroke/effects/Pages/index.aspx. Accessed April 22, 2011.
Effects of stroke. Rush University Medical Center website. Available at: http://www.rush.edu/rumc/page-1098987413801.html. Accessed April 22, 2011.
Prevention of stroke: recommendations. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/. Updated April 7, 2011. Accessed April 22, 2011.
Stroke (acute management): treatment overview. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/. Updated April 11, 2011. Accessed April 22, 2011.
Stroke and the brain. Cleveland Clinic website. Available at: http://my.clevelandclinic.org/disorders/stroke/hic_stroke_and_the_brain.aspx. Accessed April 22, 2011.
Stroke: causes. Mayo Clinic website. Available at: http://www.mayoclinic.com/health/stroke/DS00150/DSECTION=causes. Updated July 1, 2010. Accessed April 22, 2011.
Stroke effects. American Hear Association website. Available at: http://www.americanheart.org/presenter.jhtml?identifier=4761. Accessed April 22, 2011.
Stroke facts. St. John’s Hospital website. Available at: http://www.st-johns.org/services/stroke_center/stroke_facts.aspx. Accessed April 22, 2011.
Stroke: treatments and drugs. Mayo Clinic website. Available at: http://www.mayoclinic.com/health/stroke/DS00150/DSECTION=treatments-and-drugs. Accessed July 1, 2010. Accessed April 22, 2011.
Types of stroke. NYU Medical Center website. Available at: http://www.med.nyu.edu/strokecenter/aboutstroke/types/. Updated November 15, 2010. Accessed April 22, 2011.
Wood D. Stroke. EBSCO Health Library website. Available at: http://www.ebscohost.com/healthLibrary/. Updated March 28, 2011. Accessed April 22, 2011.
Last reviewed May 2011 by Rimas Lukas, MD
Last updated Updated: 5/11/2011
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © 2011 EBSCO Publishing All rights reserved.