How long is it supposed to it take for patient to recover fully after coronary artery bypass surgery?

Six weeks. Assuming a routine cabg, full recovery is usually about 6 weeks. Sometimes memory and concentration issues due to anesthetic or the heart lung bypass machine may persist a bit longer. If the procedure was a minimally invasive surgery with or without robotic components, the recovery may be shorter. Cardiac rehab may be worthwhile up to 12 weeks post operation.
6-8 weeks. It takes about 6-8 weeks for the breastbone to heal completely. After that, most physical activities are possible. One can still have pain in the chest area for many months afterwards, as the nerves that supply the skin that was cut for surgery grow back. In addition, the psychological effects of the surgery and coming to terms with having been through this, can take a much longer time.