The build-up of plaque in the inner layer of the wall of an artery may lead to narrowing and irregularity. Where the narrowing is severe, there is a risk that the vessel can block completely if a thrombus forms in the diseased segment.

Review Date: 4/15/2001 12:00:00 AM Reviewed By:Robert O’Rourke, M.D., Department of Surgery, University of California, San Francisco, CA. Review provided by VeriMed Healthcare Network.

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