'Brain attack' is caused primarily by blood clot

A stroke, sometimes called a "brain attack," occurs when blood flow to the brain is interrupted, bringing symptoms that can include temporary numbness and blindness and occasionally causing death. Four out of five strokes happen when a blood vessel is blocked by a clot, while the remaining ones occur when a blood vessel ruptures, spilling blood into the brain.

Last night, the New England Patriots released a statement saying that Tedy Bruschi had suffered a mild stroke. Earlier yesterday, a Patriots source said the popular linebacker had a leaking blood vessel.

However, one authority on strokes said the Patriots' statement that Bruschi may be released as soon as this afternoon made him skeptical that Bruschi had suffered bleeding on the brain.

"There's no such thing as a minor hemorrhagic stroke," said Dr. Jonathan Edlow, vice chairman of emergency medicine at Beth Israel Deaconess Medical Center, using the term for a stroke caused by bleeding. He noted that many hemorrhagic strokes are caused by a leaking blood vessel that requires surgery to repair.

Though strokes are normally associated with the elderly, Edlow and other stroke specialists said strokes strike people of all ages. It strikes 700,000 Americans each year, according to the American Stroke Association, and it is the nation's number three killer behind cancer and heart disease.

By stopping blood flow, a stroke keeps oxygen from reaching part of the brain. When that happens, brain cells begin to die, and the parts of the body controlled by that portion of the brain are affected, resulting, in serious cases, in loss of speech, paralysis, and even death. About 160,000 Americans die of strokes each year.

Stroke specialists praised Bruschi's family for calling an ambulance Wednesday shortly after he began experiencing a headache, numbness, and blurred vision. Some stroke symptoms can be reversed if treated quickly enough. If the stroke is caused by a blood clot, called an ischemic stroke, patients who get to the hospital within three hours of symptoms can be treated with a clot-busting drug called tPA.

It is not clear which kind of stroke Bruschi had, though his symptoms resemble a sort of mini-stroke called a transient ischemic attack in which symptoms last less than 24 hours. Such mini-strokes cause no lasting damage, but people who have had one are at risk of a more serious stroke. However, as a professional athlete, Bruschi is unlikely to have the health problems such as diabetes and heart disease that increase risk for stroke.

What treatment Bruschi receives will depend on what caused the stroke, but it could include taking a blood thinner or aspirin to discourage formation of clots.