Off-pump coronary artery bypass or 'beating heart' surgery is a form of coronary artery bypass graft (CABG) surgery performed without cardiopulmonary bypass (heart-lung machine) as a treatment for coronary heart disease. It was primarily developed in the early 1990s by Dr. Amano Atsushi. During most bypass surgeries, the heart is stopped and a heart-lung machine takes over the work of the heart and lungs. When a cardiac surgeon chooses to perform the CABG procedure off-pump, also known as OPCAB (Off-pump Coronary Artery Bypass), the heart is still beating while the graft attachments are made to bypass a blockage. Off-pump coronary artery bypass or 'beating heart' surgery is a form of coronary artery bypass graft (CABG) surgery performed without cardiopulmonary bypass (heart-lung machine) as a treatment for coronary heart disease. It was primarily developed in the early 1990s by Dr. Amano Atsushi. During most bypass surgeries, the heart is stopped and a heart-lung machine takes over the work of the heart and lungs. When a cardiac surgeon chooses to perform the CABG procedure off-pump, also known as OPCAB (Off-pump Coronary Artery Bypass), the heart is still beating while the graft attachments are made to bypass a blockage. Off-pump coronary artery bypass was developed partly to avoid the complications of cardiopulmonary bypass during cardiac surgery. The medical community believes cardiopulmonary bypass causes a post-operative cognitive decline known as postperfusion syndrome (informally called 'pumphead'), but research has shown no long-term difference between on and off pump coronary artery bypass in patients of lower risk. This is probably because the pump is not the main cause of brain damage at all, rather it is the embolic process described below.