Heart bypass surgery is also known as coronary artery bypass graft surgery that aims to replace damaged arteries in the heart. The surgeon uses blood vessels from another area of the body to restore the damaged arteries. Cardiologist recommends bypass surgery when coronary arteries become blocked or damaged. These arteries supply one's heart with oxygenated blood. The heart does not work properly if these arteries are blocked, or if the blood flow in these is restricted. This can lead to heart failure. The surgery is termed as single bypass, double bypass, triple bypass, quadruple bypass and quintuple bypass depending on the number of coronary arteries bypassed in the surgery. Bypass surgery can provide relief of angina when the location of partial obstructions precludes improving blood flow with stents. Bypass surgery is also known as coronary artery bypass grafting. Bypass surgery treats symptoms of coronary heart disease when plaque builds up inside the arteries in one's heart and blocks blood and oxygen from reaching it. One may feel chest pain, which is known as angina, irregular heartbeat and shortness of breath. Surgeons use coronary artery bypass graft to treat people who have severe coronary heart disease. The results of bypass surgery are excellent as it improves or completely relieves angina symptoms in most patients. Post successful bypass surgery, people remain symptom-free for as long as ten to fifteen years. It lowers the risk of having a heart attack and helps one live longer. One may need repeat surgery if blockages form in the grafted arteries or veins or in arteries that weren't blocked before. Taking medicines and making lifestyle changes as one's doctor recommends can lower the risk of a graft becoming blocked.