Bypass surgery is a surgical technique used to try to restore blood flow to the heart watering. There are two types: with bypass without cardiopulmonary bypass. The second case involves connecting a part of or bypass graft (piece of healthy artery or vein surgeon removes the part of the body), above and below the blockage in the artery, restoring blood flow to the heart muscle. Thus prevent bypass operation the patient has side effects and improve its recovery. Instead, bypass surgery is performed with the heart stopped while a machine handles assume its role and lungs through a pump and an oxygenator.