Assam Chief Minister Tarun Gogoi today underwent a major heart surgery at a hospital in Mumbai and doctors said he was “fit and fine” .Dr Ramakant Panda, who performed the eight-hour surgery along with his team at the Asian Heart Institute, said that the chief minister is fit and fine and has been shifted to the intensive care unit. Panda said the team performed two bypass grafts, changed the aortic valve and enlarged the artery and the operation went off smoothly. He said, adding three monitors were continuously used for the procedure.