87 percent of strokes occur when blood vessels to the brain become narrowed or clogged with fatty deposits called plaque, cutting off blood flow to brain cells. A stroke caused by lack of blood reaching part of the brain is called an ischemic stroke. High blood pressure is the most important risk factor for ischemic stroke that you can change.

Are all ischemic strokes the same?

There are three types of ischemic strokes.

• Thrombotic strokes are caused by a blood clot (thrombus) in an artery going to the brain. The clot blocks blood flow to part of the brain. Blood clots usually form in arteries damaged by arteriosclerosis.
• Embolic strokes are caused by a wandering clot (embolus) that’s formed elsewhere (usually in the heart or neck arteries). Clots are carried in the bloodstream and clog a blood vessel in or leading to the brain.
• Systemic hypoperfusion (low blood flow) occurs because of circulatory failure caused by the heart itself. The heart’s pumping action fails and too little blood reaches the brain. This is how a heart attack may cause a stroke.

How are ischemic strokes diagnosed?

When someone has shown symptoms of a stroke or a TIA (transient ischemic attack), a doctor will gather information and make a diagnosis. He or she will review the events that have occurred and will:

• get a medical history
• do a physical and neurological examination
• have certain laboratory (blood) tests done
• get a CT or MRI scan of the patient
• study the results of other diagnostic tests that might be needed
  

How are ischemic strokes treated?

Acute treatment is the immediate treatment given by the healthcare team when a stroke happens. The goal of acute treatment is to keep the amount of brain injury as small as possible.

The only FDA approved drug to treat ischemic stroke is tissue plasminogen activator (tPA).  It is a clot busting drug. tPA must be given within 4.5 hours of the first symptoms of stroke. Medication may also be used to treat brain swelling that sometimes occurs after a stroke.

Preventive treatment may be given before or after a stroke happens. When someone has a stroke, they are at risk of another. Once the medical team identifies what caused the stroke, they may prescribe treatments or procedures to reduce the risk of a second, such as:

• Antiplatelet agents such as aspirin and anticoagulants such as warfarin interfere with the blood's ability to clot and can play an important role in preventing stroke.
• Carotid endarterectomy is a procedure in which blood vessel blockage is surgically removed from the carotid artery in the neck.
• Doctors sometimes use balloon angioplasty and implantable steel screens called stents to treat cardiovascular disease and reduce fatty buildup clogging a vessel that may make it easy for clots to form in the bloodstream.

Sometimes a stroke is the first sign a person has of other health conditions, such as high blood pressure, diabetes or atrial fibrillation (a heart rhythm disorder). If any of these are diagnosed, the healthcare team will prescribe appropriate treatment.


How can I learn more?

• Talk to your doctor, nurse or other healthcare professionals. Ask about other stroke topics. 
• Call 1-888-4-STROKE (1-888-478-7653) or visit us online at StrokeAssociation.org to learn more about stroke.
• Call the American Stroke Association’s “Warmline” at 1-888-4-STROKE (1-888-478-7653), and:
  • Sign up to get Stroke Connection, a free magazine for stroke survivors and caregivers.
  • Talk to other stroke survivors and caregivers and find local support groups.

We have many other fact sheets to help you make healthier choices to reduce your risk, manage disease or care for a loved one. Visit strokeassociation.org/letstalkaboutstroke to learn more. 

Knowledge is power, so Learn and Live!
 

Do you have questions for your doctor or nurse?

Take a few minutes to write your own questions for the next time you see your healthcare provider:

What can I do to help prevent another stroke?

What medications may I be given?

©2012, American Heart Association