Coronary Artery Bypass Grafting (CABG) is a type of heart surgery used to treat ischaemic heart disease. Ischaemic heart disease is characterised by atherosclerosis and blockage of the coronary arteries (the blood vessels supplying the heart muscle). CABG surgery attaches new and healthy vessels from the inner leg, wrist or inner chest, to the coronary arteries at a site beyond the blockage. This allows the blockage to be bypassed and blood to get to the rest of the heart muscle. CABG therefore treats and prevents angina and heart attacks.