open-heart surgery

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Surgery in which the thoracic cavity is opened to expose the heart and the blood is recirculated and oxygenated by a heart-lung machine.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun heart surgery in which the rib cage is spread open, the heart is stopped and blood is detoured through a heart-lung machine while a heart valve or coronary artery is surgically repaired