Stroke

Each year, hundreds of thousands of adults, teens, and children suffer from strokes. A stroke occurs when parts of your brain lose crucial blood flow, damaging blood cells and lessening brain function. Below is more information on different kinds of stroke and what causes them.

Ischemic ("iss-KEE-mick") Strokes

Ischemic strokes are the most common type of stroke, accounting for 87 percent of all strokes. In an ischemic stroke, blood flow to the brain is cut off or greatly reduced, depending on the cause of ischemic stroke. A thrombotic stroke happens when a blood clot (also called a thrombus) forms inside an artery leading to the brain, blocking blood flow. These blood clots are more common in those whose arteries have plaque or fatty material, limiting blood flow. An embolic stroke is also caused by a blood clot, but a clot that forms somewhere else in the body (commonly in the heart), and travels toward the brain.

To treat an ischemic stroke, the first goal is to restore normal blood flow to the brain, followed by medications and treatments to alleviate pain, lessen symptoms, and prevent future complications. Medications like tPA (tissue plasminogen activator) or anticoagulants will help to dissolve blood clots and prevent future issues.

Physicians may also employ a catheter to deliver medication and remove the blood clot. In rare cases, cerebral bypass surgery may also be used to regain normal blood flow to the brain. With all stroke treatment, time equals muscle, and getting to the hospital as soon as a stroke occurs is crucial to lessening permanent damage and disability.

Hemorrhagic ("heh-muh-RAW-jick") Strokes

Hemorrhagic strokes occur when a blood vessel leading to the brain bursts causing hemorrhaging. Blood floods into the surrounding brain tissue, taking blood away from other parts of the brain. The resulting bleeding can also cause the brain to swell and bruise, and occasionally rupture (an aneurysm).

There are two types of brain hemorrhages that can cause a stroke. An intracerebral hemorrhage (ICH) happens when a blood vessel breaks deep inside your brain, while a subarachnoid hemorrhage (SAH) happens when a broken blood vessel causes blood to build up on the brain’s surface.

For a hemorrhagic stroke, the first goal is to stop the bleeding in the brain and relieve any extra pressure on the brain. Surgery may be required to drain excess blood, clear away dead brain tissue, or temporarily remove a part of your skull to ease pressure.

Your doctor will also prescribe medications that lower high blood pressure (hypertension) and can help reduce the bleeding from a hemorrhagic stroke. These medications can also help prevent future strokes and complications.

Transient Ischemic Attacks (TIA)

TIAs are also called a "mini-stroke" because the symptoms are like that of a stroke, but don't last long. A TIA happens when blood flow to part of the brain is blocked or reduced, often by a blood clot. After a short time, blood flows again and the symptoms go away. TIAs must be taken very seriously because they are indicators that you are likely to have a stroke soon.

Thrombotic Strokes

Thrombotic strokes, also called cerebral thrombosis, occur when a blot clot (thrombosis) forms inside an artery in the brain, blocking blood flow. Sometimes the clot forms in one of the arteries in the neck that transport blood to the brain.

Embolic Strokes

Embolic strokes, also known as cerebral embolism, is caused by a blood clot. But unlike the thrombotic stroke, the clot originates somewhere other than the brain. Embolic strokes occur when a piece of a blood clot breaks loose and travels in the blood stream in the brain. It travels until it reaches a point where it can go no farther and blocks up the vessel, cutting off the blood supply. The sudden blockage is called an embolism.

Brain Aneurysms and AVMs

AVMs are a a bulging, weak area in the wall of an artery that supplies blood to the brain. In most cases, a brain aneurysm causes no symptoms and goes unnoticed.

In rare cases the brain aneurysm ruptures, releasing blood into the skull and causing a stroke. A brain arteriovenous malformation (AVM) is a cluster of abnormal blood vessels in the brain that can burst and cause bleeding in the brain, leading to a stroke.

A stroke occurs when blood flow to part of the brain suddenly stops. It can happen because of a blood clot that blocks a blood vessel (ischemic stroke) or because a blood vessel in your brain bursts (hemorrhagic stroke). Your brain cells need oxygen and nutrients carried by the blood, so when a stroke happens, brain cells begin to die within minutes. Use the links below to learn more about strokes and how to respond when one is happening.

Each year approximately 795,000 people in the U.S. suffer a stroke. About 600,000 of these are first attacks and 185,000 are recurrent attacks. Although nearly three-quarters of all strokes occur in people over age 65, strokes can and do occur at any age. The chart below can help you assess your risk.

To use the chart, assign one point per row based on where you fall for that risk factor. Add up your total points in each column to calculate your level of risk for a stroke.

• High Risk = 3 or more points from the red column
• Moderate Risk = 4-6 points from the yellow column
• Low Risk = 6-8 points from the green column

Most of the risk factors in the chart above can be controlled or even eliminated. To help prevent a stroke and improve your overall health you can:

• Visit your doctor regularly. Your doctor can check for "silent" risk factors like high blood pressure and help you properly manage any chronic illness such as diabetes.
• Stop smoking. Quitting now will dramatically improve your health both now and in the future. It will lower your risk of having a stroke, as well as lower your risk of many other serious medical conditions. To get help quitting, talk to your doctor or call this free, confidential phone line: 1-888-567-TRUTH (1-888-567-8788). The Spanish language line is 1-877-629-1585. Read more about how to successfully quit: Quitting Tobacco: Your Journey to Freedom.
• Maintain a healthy weight. This will help you control your blood pressure, cholesterol, and diabetes — and lower your chance of heart disease and stroke. Talk to your doctor or dietitian about how to lose weight safely, slowly, and permanently. You can also check out our LiVe Well Center to learn more about what a healthy weight is and how you can reach it.
• Exercise. Physical activity protects your heart, brain, and bones. Exercising makes you stronger, gives you more energy, and helps you cope with daily stress. Aim for 30 minutes of moderate exercise on most days of the week. The 30 minutes can be broken up throughout your day. Some simple ways to get some exercising in: take the stairs instead of an elevator, park at the end of parking lots, walk the dog, etc. Our LiVe Well Center offers a list of classes administered by healthcare professionals that can help you exercise safely.