What Is an Ischemic Stroke?

An ischemic stroke occurs when a blood clot blocks an artery supplying blood to the brain, usually because of plaque build-up on the artery walls. The brain needs a constant supply of blood to bring nutrients and oxygen. When a clot blocks the artery, blood can't reach the brain, which can quickly damage brain cells.

Types of Ischemic Stroke

There are two main types of ischemic stroke: thrombotic and embolic. They're similar in that each involves a blood clot in the brain, but they differ in the source of the clot:

• Thrombotic strokes are caused by a blood clot originating in the brain, called a thrombus.
• Embolic strokes result from an embolism, a blood clot in the brain that traveled there after forming elsewhere, often in the heart or large arteries.

Transient Ischemic Attack

Transient ischemic attacks (TIAs) are often called mini strokes because they resemble ischemic strokes. Like a full ischemic stroke, a TIA occurs when a blood clot blocks blood flow to the brain. However, a TIA resolves on its own after a short time (transient). TIAs don't cause lasting damage on their own, but they usually indicate that a person is at very high risk for a full stroke soon. If you experience a TIA, you should seek medical attention immediately before you have a true stroke.

Ischemic Stroke Symptoms

The signs and symptoms of ischemic stroke can vary depending on where in the brain the stroke is happening. Both types of ischemic stroke have the same kinds of symptoms, including:

• Vision problems such as blurred or double vision
• Difficulty communicating (slurred speech or inability to speak)
• Muscle weakness or facial drooping on one side
• Clumsiness or reduced coordination
• Neck stiffness
• Confusion, difficulty understanding, or memory loss
• Sudden, severe headaches

Learn more about stroke causes and symptoms

Causes of Ischemic Stroke

Ischemic strokes are caused by blood clots in the brain. But what causes blood clots in the brain? There are many reasons a blood clot or other blockage forms, including:

• Atherosclerosis: Hardening of the arteries due to plaque buildup can make it easier to block the artery.
• Atrial fibrillation: An irregular heartbeat disorder can form clots and cause them to break off and become embolisms.
• Clotting disorders: Some disorders result in increased clotting, which makes a clot in the bloodstream more likely.
• Fat in the bloodstream: Embolisms made of fat, rather than blood clots, can cause stroke.
• Infection: In some cases, infected tissue can form an embolism instead of a blood clot.

Ischemic Stroke Side Effects

Most ischemic stroke symptoms can become lasting side effects of stroke, especially if you don't diagnose and treat the stroke quickly. After a stroke, you may continue to have difficulty communicating, weakness or paralysis on one side of the body, drooping facial muscles, confusion, and more.

Like stroke symptoms, the lingering effects you experience depend on the area of the brain where the stroke happened and how severe an ischemic stroke is.

Diagnosis and Treatment for Ischemic Stroke

Early treatment is crucial for recovery. The faster doctors restore blood flow to the brain, the less permanent brain damage you will suffer and the more likely you are to recover your abilities.

When you arrive at the hospital, your doctor will perform a physical exam and ask some questions. This helps the doctor look for stroke symptoms and evaluate their severity. Then, the doctor will order imaging tests to determine what kind of stroke you’ve experienced, what caused it, and where the blockage is. Once the diagnosis is complete, they'll choose the best ischemic stroke treatment for your situation.

How Do You Treat an Ischemic Stroke?

There are two main types of ischemic stroke treatment: medication called "thrombolytics" and a procedure called a thrombectomy.

Thrombolytics dissolve the blood clot to free up the blocked artery. Depending on your case, doctors may administer thrombolytics through an IV or insert a tube into an artery to apply the medication directly to the blood clot in your brain.

In a thrombectomy, a doctor inserts a special tool on a catheter into one of your arteries, moves it through your bloodstream to the blockage, and uses a mechanical tool to break up or remove the clot.

Find out more about how strokes are treated

FAQs About Ischemic Stroke