Discuss why some coronary bypass surgeries have to be repeated.

Coronary artery bypass surgeries: This is a type of surgery that improves the blood flow condition to the heart. It is generally used for the people who have severe heart disease. It occurs when the plaque condition develops inside the coronary arteries; this plaque is rich in fats, cholesterol, calcium and many other substances found in the blood. Therefore the plaque can block the arteries hence reducing the proper blood flow to the heart muscle. This can lead to angina, shortness of breathe, arrhythmia or heart attack can occur. In this treatment a healthy artery is connected or grafted to the blocked coronary artery area. Thus will create a new passageway for oxygen rich blood to pass.