2 percent of vessel plaques cause clots

NEW YORK, May 6 (UPI) -- U.S. researchers say they have evidence to explain what separates average blood vessel plaque from those that trigger blood clots.

The study, published in the journal Cell Metabolism, suggest drugs designed to tackle a form of cellular stress might be useful in treating heart disease.

"Just about everybody in our society has atherosclerosis by the time we reach 20," Ira Tabas of Columbia University in New York said in a statement. "The billion-dollar question is why 98 percent cause no problem, and 2 percent do."

In atherosclerosis, lipid, inflammation and white blood cells known as macrophages build up at various spots along blood vessel walls and the vast majority of these lesions will never cause any problem, but the rest -- some 2 percent of all plaques -- will eventually lead to the development of an acute blood clot and to heart attack, sudden death, or stroke.

The study adds support to the notion that so-called endoplasmic reticulum stress together with the body's natural way of coping with that stress may result in blood clots.

The endoplasmic reticulum is a cellular component that serves two major functions -- it is the site where new proteins are made, folded, and transported. It is also the central storage depot for the cell's calcium and controls its release, Tabas explained.