Stroke

Brain cells need a constant supply of oxygen and nutrients. They are delivered by a network of blood vessels that reach every part of the brain. When something cuts off that supply, brain cells downstream begin to die. The injury that follows is called a stroke.

Most strokes strike when a blood clot becomes lodged in one of the brain's arteries, blocking blood flow. In some cases, the clot forms inside the artery, usually because a cholesterol-filled plaque inside the artery breaks open. This is called a thrombotic stroke. In other cases, a blood clot or a solid mass of debris that originates elsewhere travels to the brain, where it blocks a brain artery. This is called an embolic stroke. A third type of stroke, hemorrhagic stroke, occurs when a blood vessel in the brain bursts.

Since different areas of the brain are responsible for different functions, symptoms of stroke vary. They can be changes in sensation, movement, sight, speech, balance, and coordination. Sometimes a stroke is preceded by one or more transient ischemic attacks (TIAs). These are brief episodes of stroke-like symptoms that last for a few minutes — or possibly up to 24 hours — but that go away on their own.

If you think that you, or someone you are with, is having a stroke, call 911 right away. The sooner you call, the sooner treatment can begin — "time is brain," as emergency room doctors say. The type of treatment depends on the type of stroke that has occurred. If the brain's blood supply is restored quickly and completely, a full recovery with little or no disability is possible. The more widespread the damage, and the greater delay of treatment, the more severe and long-lasting the damage.

Recovery after a stroke depends on how well healthy areas of the brain take over duties that had been performed by the damaged brain tissue. To some extent, especially in children and young adults, recovery is possible because of the brain's ability to compensate for damage in one area by working harder in another — by relying on alternate wiring for some functions or by rewiring around the injured site. When such rewiring isn't possible, rehabilitation techniques can help the brain recover function.

Stroke Articles

Traffic noise may raise stroke risk

Exposure to traffic noise may slightly raise a person's risk of being hospitalized for a stroke and from dying of any cause. The noise may boost stress hormone levels, which can raise the risk of cardiovascular disease. More »

How to avoid a disabling stroke

Reducing your risk factors for stroke, learning to recognize stroke symptoms, and calling 911 when needed can lower your risk of a disabling stroke. (Locked) More »

Stroke risk when you have atrial fibrillation

Atrial fibrillation (afib) is among the most common heart rhythm irregularities. During a bout of afib, blood can stagnate and form clots, which can travel to the brain. More than one in six ischemic strokes can be traced to atrial fibrillation. Because effectively detecting and treating afib could avert many strokes, doctors have devised an improved scoring system to identify people with afib who are at high stroke risk. In addition, newer anticoagulant drugs offer safer and more convenient stroke protection for more people. (Locked) More »

When the blood supply to the kidneys suffers

The buildup of cholesterol-laden plaque in the arteries that supply the kidneys causes a condition known as atherosclerotic renal artery stenosis. When the kidneys don’t get enough blood, the result can be a rise in both blood pressure and fluid levels in the body. This increases a person’s risk of a heart attack or a stroke. Treatments include lifestyle changes, medications, and in some cases, an artery-opening stent to help restore blood flow to the kidneys. (Locked) More »

How a sleep shortfall can stress your heart

Chronic sleep deprivation strains the cardiovascular system, which may raise the risk of a heart attack or stroke. The most common cause, insomnia (trouble falling and staying asleep) often stems from stress, depression, or anxiety. Sleep apnea, which causes loud snoring and frequent breathing lapses during sleep, is more prevalent in people at risk for heart disease. (Locked) More »

Lowering blood pressure: How low should you go?

High blood pressure wreaks havoc in the circulatory system. It is a key contributor to heart attack and stroke. However, blood pressure that is too low can lead to problems such as blurry vision, dizziness, confusion, and fainting, which can diminish quality of life, especially in older people. In recognition of the trade-off between lower risk of cardiovascular disease and overall well-being, experts from three major heart groups have issued an updated set of blood pressure guidelines that call for a flexible approach in designing medication regimens for treating hypertension. (Locked) More »

To lower stroke risk, be sure to get this B vitamin

People with high blood pressure should be sure they’re getting enough of the B vitamin folate in their diets, which may lower the risk of a stroke. The recommended daily intake of folate is 400 micrograms per day. Folate occurs naturally in many foods, but especially green leafy vegetables, beans, and citrus fruits. Most grain products (including wheat flour, cornmeal, pasta, and rice) are fortified with the synthetic version of the vitamin, known as folic acid. (Locked) More »