Coronary artery bypass surgery is a form of heart surgery. Heart bypass surgery can improve blood flow to the heart by bypassing blocked arteries. The arteries are often blocked or clogged by buildup of fat, cholesterol and plaque. In this type of heart surgery, the chambers of the heart are not opened to perform the surgery. The attachment of the bypass grafts is done on the outside of the heart. It usually requires that chest be opened to perform the surgery.

How is coronary bypass done?
The surgery involves taking a portion of a blood vessel from another part of the body and creating a different route for blood to flow around the blocked section of the coronary artery. This portion of a blood vessel is usually taken from a vein in your leg or an artery in your chest wall. The blood vessel that bypasses the blocked artery is called a bypass graft. Cardiopulmonary bypass is used for most coronary artery bypass operations. This involves stopping the heart and re-routing the blood through a heart-lung machine temporarily while the surgery is in progress. The surgery can take 2-6 hours depending on factors such as how many bypasses you need, if this is a repeat heart surgery, and your medical condition going into the surgery.