Dr. Mark Fisher, director of the UCI Stroke Center, and colleagues found that in the carotid artery, the primary source of blood to the brain, plaques form lesions that support the growth of the stroke-causing blood clots, which can either block the artery or break off and travel into the brain.

The findings suggest an increased need for early identification and treatment of this plaque growth for people who are at risk for stroke. Strokes are the leading reason for disability and the third leading cause of death in the United States today, and 80 percent of these strokes are caused by blood clots. Study results appear online in Stroke, a peer-reviewed journal of the American Heart Association (www.strokeaha.org).

"Plaque growth in the carotid artery is the most important surgically correctable cause of stroke," said Fisher, the study leader. "However, there has been only limited information about the nature of these plaque lesions, and this study provides some of the best evidence yet showing their link to stroke."

The work of Fisher and his colleagues shows the importance of several pathologic features of the plaques that produce stroke symptoms. Extensive analyses were performed on surgical specimens from two of the most important clinical trials in the history of stroke research: the North American Symptomatic Carotid Endarterectomy Trial and the Asymptomatic Carotid Atherosclerosis Study. Fisher's study constitutes the only formal interaction between these two historically important studies.

Fisher and his colleagues found that carotid-artery plaques most likely to cause stroke first develop depressions in their surface called ulcerations. Blood can pool in these ulcerations and ultimately
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Contact: Tom Vasich
tmvasich@uci.edu
949-824-6455
University of California - Irvine
7-Feb-2005