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coronary bypass surgery

A surgical procedure to restore normal blood supply to the heart by creating new routes for the blood to travel into the heart when one or both of the coronary arteries have become clogged or obstructed (possibly due to atherosclerosis). These new routes are created by removing blood vessels from another part of the body (most often the veins of the leg) and grafting them onto the heart to bypass the clogged arteries.

Note

Often, people will call this kind of surgery a double, triple, or quadruple bypass, referring to the number of diseased coronary arteries that had to be bypassed during the operation.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.