University of Washington (UW) researchers have gathered evidence that dangerous plaques in blood vessels can rupture by overproducing protein-digesting enzymes. Plaques are fat-laden rough spots in the otherwise smooth walls of arteries. When a plaque ruptures, blood accumulates inside of it, a process known as plaque hemorrhage. The plaque enlarges and artery-blocking clots can form. If the flow of oxygen-rich blood is restricted, a heart attack, stroke, or damage to other organs can occur. Most adults have some degree of plaque in their arteries... 
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