What is an ischemic stroke?

If an artery in the brain becomes blocked, the stroke is called an ischemic stroke. The normal flow of blood cannot get past the blockage, and the brain cells get damaged because they do not receive what they need.
Ischemic stroke is a type of stroke where blood vessels to the brain are blocked by plaques that either formed in those vessels or moved from a different body part and traveled to the brain vessels to block them, cutting off the blood supply. When this happens, the brain is starved of blood and nourishment, leading to symptoms.
Ischemic stroke, which accounts for about 87% of strokes, results from an interruption in blood flow through an artery supplying a specific area of the brain. Four basic kinds of problems can block an artery and interfere with blood flow. When brain cells die as a result of ischemic stroke, the resulting injury to the brain is called a cerebral infarction.

If the brain tissue whose blood supply was interrupted recovers rapidly, the event is called a transient ischemic attack, or TIA or ministroke. The presumption is that blood flow interruption was short (transient) and the affected brain cells temporarily ceased to function, but then recovered.
Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Ischemic strokes occur when the brain tissue is starved of blood. Anything that prevents blood from reaching the brain can cause this type of stroke; a narrowed or blocked blood vessel supplying the brain, a clot that has formed in a brain's blood vessel that blocks flow (thrombosis), or a clot that has travelled from elsewhere in the body (embolism).
As soon as the brain is deprived of nutrient- and oxygen-rich blood, brain neurons die. The longer the tissue is starved, the more damage is done. Neurons stop sending and receiving messages to and from parts of the body and faculties begin to falter. Symptoms can last minutes, hours or days and the effect can be large, small, temporary or permanent. About 85% of cerebrovascular accidents are caused by ischemic strokes.
Transient ischemic attacks or TIAs are referred to as mini ischemic strokes because their symptoms are temporary and typically last less than 24 hours. People who have mini TIAs are prone to a full-on stroke in the future.

A stroke is what happens when the brain is deprived of blood and oxygen. This can happen in one of two basic ways: through a blockage in an artery leading to the brain (for example, the carotid arteries) or because a blood vessel carrying blood to the brain ruptures. An ischemic stroke is when blood flow to the brain is blocked either by a blood clot that has lodged in a blood vessel or because of narrowed arteries caused by build-up of a fatty substance called plaque.

If you are having an ischemic stroke, the focus at the hospital will be on reopening the blocked blood vessel through the use of clot-busting drugs called thrombolytics, interventional procedures in which treatments are delivered via a thin tube called a catheter, or surgery to remove the blockage. Stopping a stroke quickly is critical to minimizing brain damage and the risk of death.

Patients who suspect they may be having a stroke should not assume it is caused by a blood clot and take aspirin. Let the emergency room care team make the diagnosis. If the stroke is not cause by a blockage but instead is caused by bleeding, aspirin could worsen the bleeding. If you think that you or someone around you is having a stroke, call for emergency help. In the United States, this means calling 9-1-1. It is vitally important to get to a hospital emergency room as quickly as possible.

Ischemic strokes are caused by blood clots. They account for about 80 percent of all strokes. Clots in this type of stroke are classified either as cerebral thrombosis or as cerebral embolism.

Cerebral thrombosis is the more common cause of ischemic stroke. It is caused by a blood clot that is formed in an artery in, or leading to, the brain. The clot usually is the result of fatty plaque which has built up in the arteries. The key difference between what happens in a stroke and what happens in a heart attack is that the arteries in the brain are much smaller than those of the heart, so a clot does not have to be very big to cause problems.

A cerebral embolism occurs when a wandering clot makes its way to the brain, generally coming from the heart. This kind of clot tends to happen suddenly, unlike thrombosis, which builds over time.

In either event, the clot cuts off blood flow to the brain, which kills brain cells.

When an artery in the brain either bursts or has a blockage, it causes a stroke. There are two types of strokes. Hemorrhagic strokes result from bleeding inside the brain, which may occur if a blood vessel or aneurysm (a swelling in an artery) ruptures. Ischemic strokes, which are the most common type of strokes, result when a blood clot or accumulation of fat in an artery causes a reduction in blood flow in the brain. Strokes are a medical emergency and require quick treatment.

Continue Learning about Ischemic Stroke

What are the symptoms of an ischemic stroke?
Sigma NursingSigma Nursing
Oftentimes, ischemic strokes strike suddenly. In many cases, people will first experience an excruci...
More Answers
What is an embolic stroke?
Univ. of Nev. School of Medicine, Family MedicineUniv. of Nev. School of Medicine, Family Medicine
An embolic stroke is a stroke caused by either a traveling blood clot or a piece of plaque (fatty de...
More Answers
Do ischemic strokes affect men and women differently?
Honor Society of Nursing (STTI)Honor Society of Nursing (STTI)
Strokes are the fifth-leading cause of death in the United States. Overall women (including the elde...
More Answers
Is an ischemic stroke serious?
Steven A. Meyers, MDSteven A. Meyers, MD
Yes, strokes are very serious medical emergencies that require urgent treatment. Strokes can lead to...
More Answers

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.