A stroke is sometimes referred to as a "brain attack," because the process that causes it is similar to what happens in a heart attack. Strokes occur when the blood flow to a part of the brain is blocked. If the blockage is not relieved, brain cells will die. The body functions that depend upon that part of the brain will suddenly be lost. The size of the stroke and the area of the brain where it occurs determine what the symptoms will be. A small stroke may produce mild weakness in one arm or one leg, and you may recover completely, while a larger stroke may paralyze an entire side of the body or leave you unable to communicate.

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A stroke is an emergency, just like a heart attack. However, unlike a heart attack, a stroke is usually not painful. That's why it's important to learn the warning signs and symptoms of a stroke so you can react quickly.

Print out a handy guide to stroke warning signs

Anyone who experiences any of the warning signs of stroke should call 911 and get to a hospital immediately. Stroke requires urgent treatment in order to have the best outcome. Do not wait to see whether the symptoms will get better. The longer you delay getting to a hospital, the more likely it is that the damage to your brain will be severe or permanent.


Stroke is the third leading cause of death in the United States. Strokes kill twice as many American women as breast cancer. Each year, 750,000 Americans suffer a stroke (one person every 45 seconds) and 160,000 have a fatal outcome. Of those who survive, many suffer permanent disability - stroke is the leading cause of disability in adults.

Meet a man who had a stroke.
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Stroke risk increases with age. After age 55, your chance of having a stroke doubles every ten years. Two thirds of all strokes occur in people older than 65.

Risk factors for stroke are generally the same as those for heart attack – high blood pressure, smoking, high cholesterol, diabetes, family history, etc. But there is another risk factor for stroke – an abnormal heart rhythm called atrial fibrillation.

Atrial Fibrillation (often called A-fib or AF) is a relatively common disorder that affects more than two million Americans. Most of them don’t know they have it. The risk of stroke is five times higher in people who have AF.

The heart has four chambers. The upper chambers are the atria (left atrium, right atrium), where blood enters the heart. The lower chambers are the ventricles, which pump blood out of the heart to the body.

A normal heartbeat involves coordinated movement of all four chambers. It begins with the atria and proceeds to the ventricles. In AF, instead of this normal synchronized movement, there is a disorganized twitching of the atria, called fibrillation. When that happens, a clot may form inside the heart. A piece of the clot may then break off, be pumped out of the heart, and travel to the brain, causing a stroke.

AF causes about 15-20% of all strokes. The good news is that these strokes can be prevented. If everyone with AF received proper treatment, we could prevent about 80,000 strokes every year.

AF can develop in anyone, but becomes much more common as we grow older. About 5% of people age 65 have AF, while about 10% of people over 75 are affected. It can occur in otherwise healthy people, but is more common in those who have high blood pressure, heart disease or lung disease.

There may be no symptoms at all, and you may be completely unaware that you have AF. Some people can sense that their heartbeat isn’t quite right, with frequent missed, skipped or extra beats. This is sometimes described as a "fluttering", "pounding", or "racing" sensation in the chest. Others may experience occasional dizziness, faintness or light-headedness.

Whether you have any of these symptoms or not, you may be able to discover whether you have AF simply by checking your pulse.

You can discover whether your heartbeat is irregular by learning to take your own pulse. Its simple, free, requires no equipment, and we’ve proven that it works! If you detect an irregular pulse, you can check with your doctor to see whether it is due to AF or to some other condition

Click on continue below to learn how to take your pulse. It’s easy!