When your coronary arteries are blocked, your doctor may treat the problem by giving the blood a new pathway to the heart.
During coronary artery bypass graft surgery (also called CABG, or "cabbage") a blood vessel is removed or redirected from one area of the body and placed around the area or areas of narrowing to "bypass" the blockages and restore blood flow to the heart muscle. This vessel is called a graft.
These substitute blood vessels can come from your chest, legs, or arms. They're safe to use because there are other pathways that take blood to and from those tissues. The surgeon will decide which graft(s) to use depending on the location of your blockage, the amount of blockage, and the size of your coronary arteries.