Heart surgeons can use one of two techniques to perform a coronary artery bypass. They can perform it using the heart-lung machine, which means the heart is stopped during the procedure and the machine takes over, or they can perform the bypass while the heart continues to beat. It is a little more technically challenging to do it off-pump when the heart is beating, but it can be done just as effectively. I will explain the different reasons for each procedure. The key is to find a surgeon that is comfortable with both options.