Arterial Ischemic Stroke (AIS)
What is arterial ischemic stroke (AIS)?
An arterial ischemic stroke (AIS) occurs when blood flow in an artery to the brain is blocked by narrowing of the artery, or when a blood clot forms in the artery and blocks the supply of blood to a part of the brain. Ischemia, or ischemic, comes from the Greek word to "keep back" or "stop" the supply of blood to an area.
A blockage of blood flow in an artery can happen in several different ways:
- Embolism: The blood clot can form in some other part of the body (often the heart) and travel to the brain. It gets stuck in a blood vessel of the brain. This moving clot is often called an embolus or embolism. This clot happens most of the time in a child with underlying heart disease.
- Thrombosis: The blood clot can form over time in an artery that supplies blood to the brain. It can eventually block the artery and the supply of blood to the brain. This clot is sometimes called a thrombus.
- Clotting disease: Thick blood. Some children have underlying conditions that cause their blood to "thicken" and clot.
- Narrow arteries: Other children may have arteries that are very narrow leading to a risk that even a tiny clot could get stuck in them, or causing decrease in blood flow to a low enough level to cause a stroke.
- Damaged arteries: Some children may have arteries that are damaged by trauma or inflammation leaving a rough or jagged inner lining where blood clots can get stuck. These clots can build up enough so that eventually the artery is clogged and no blood can flow through.
The blood carries oxygen and other important nutrients to the brain. The brain needs oxygen to survive. If a part of the brain does not receive oxygen from the blood for a certain period of time, the tissue in that part of the brain will become damaged or die.
For many children, it can be hard to find out exactly what caused the blockage of the artery that led to the stroke. Some of the leading causes of childhood stroke include:
- Heart disease - mostly congenital heart defects (present at birth)
- Sickle cell anemia
- Narrow or damaged blood vessels in the brain or neck
- Accidents involving the head and neck region
- Blood clotting disorders
- Moyamoya disease
- Head and neck radiation for cancer
- Serious infections, especially meningitis from bacteria
- Drug abuse
- Other childhood diseases (for example, Chicken Pox)
- Chronic metabolic disorders
Signs and symptoms
In children and teenagers
Children and teenagers may have one or more symptoms when they are having an arterial ischemic stroke. Typically these symptoms occur suddenly. They include:
- Weakness or numbness of the face, arm or leg, usually on one side of the body
- Trouble walking due to weakness or trouble moving one side of the body
- Problems speaking or understanding language, including slurred speech, trouble trying to speak, inability to speak at all, or difficulty in understanding simple directions
- Severe headache especially with vomiting, sleepiness or double vision
- Trouble seeing clearly in one or both eyes
- Severe dizziness or unsteadiness that may lead to losing balance or falling
- New appearance of seizures, especially if they affect one side of the body and are followed by paralysis on the side of the seizure activity
In newborns and infants:
- Extreme sleepiness
- A tendency to use only one side of their body
Sometimes there are no symptoms with newborns and very young infants until they grow older. Then, they may have trouble with movement on one side of the body.
What you can do
If your child is experiencing any of the symptoms of a stroke, you should:
- Dial 911 or go to your nearest hospital Emergency Department.
- Have your child lie flat.
- Do not give your child anything to eat or drink.
- Suggest that your local medical professional contact the CHOP Stroke Program for consultation. They may contact the CHOP operator at 215-590-1000 and ask for the Stroke team to be paged.
Testing and diagnosis
The Stroke team will want to find out as much information as possible to diagnose your child's stroke and the reasons why the stroke occurred.
The Stroke team will perform a thorough physical exam including a neurological exam to gain more information about how your child's brain is currently working.
The Stroke team will request that blood tests be done to test to see if your child has any underlying blood problems that could cause a stroke.
The Stroke team will request that various types of tests be done that will give a better picture or "image" of your child's brain. These tests may include computed tomography (CT) scans, magnetic resonance imaging (MRI), magnetic resonance angiogram (MRA) or cerebral angiogram (also called an arteriogram). If the Stroke Program team feels more information about your child's heart may be useful, they may order an echocardiogram.
Depending on your child's symptoms, the Stroke team may feel a need to order some other tests. These may include a lumbar puncture (LP) also known as a "spinal tap" to look for signs of infection or inflammation that may have caused the stroke.
Immediately after the stroke, the treatment given to your child will focus on things that will prevent the stroke from getting worse. This will include ensuring that your child has enough fluids (given through an IV or intravenous needle typically put in a vein in the child's arm or hand) and keeping the child lying flat. Medications for any pain symptoms may be given as well.
Further treatment will vary depending on the suspected cause of the stroke. Some treatment may focus on preventing blood clots from happening in the future. In this case anticoagulant ("anti-clot") medications (such as COUMADIN, HEPARIN or LOVENOX) or an antiplatelet medication such as aspirin (that prevents blood platelets from clumping together to form a clot) may be prescribed. In addition, other treatment will focus on preventing fever and keeping the sugar levels in the blood at normal levels.
Outlook and long-term care
How much the stroke will affect your child's day-to-day life depends on the location and severity of the stroke. Some strokes cause mild problems. Some cause more severe problems. Some children may continue to have seizures.
Your child's Stroke team will consult with the Rehabilitation team for advice on how best to help your child recover. Rehabilitation uses a structured series of exercises to help your child recover from the effects of the stroke. Therapy usually begins within 48 hours of admission, provided your child is medically stable and is able to tolerate these activities. Members of the Rehabilitation team may include a physical therapist (PT), occupational therapist (OT), speech therapist, neuropsychologist and physiatrist (Rehab or "PM &R" Physician).
Depending on the results of their assessments, it may be recommended that your child have further rehabilitation. This rehabilitation could range from a stay in the inpatient rehabilitation unit, to Day Hospital rehabilitation, to outpatient rehabilitation appointments. Rehabilitation may last from weeks to months depending on your child's needs.
It's important to keep in mind that children recover more quickly from a stroke as compared to adults. Members of the Stroke team and the Rehabilitation team will continue to assist you and your child in the recovering process and help your child return to a more normal lifestyle as soon as possible. If your child is school age, we will work with your child's school to recommend any needed changes to your child's curriculum and school day.
Reviewed by Rebecca N. Ichord, MD