David Attenborough 'doing well' after urgent heart surgery forces him to pull out of sell-out Australian tour Presenter, 87, fitted with a pacemaker today on urgent advice of cardiologist Sir David had been due to embark on sold-out tour of Australia next week Spokesman said doctors believe broadcaster is 'doing well' after operation Veteran broadcaster Sir David Attenborough has undergone urgent heart surgery to insert a pacemaker. A spokesman for the 87-year-old naturalist, who was forced to cancel a sell-out speaking tour of Australia due to the sudden procedure, said doctors believed that the TV star was doing well. 'Sir David has now had the operation and his doctors are satisfied with his progress,' he said. Surgery: The veteran wildlife presenter, seen on the Jonathan Ross Show in February this year, is undergoing heart surgery today Earlier, he said that the TV documentary-maker, who has been named Britain's greatest living national treasure, was still his 'lively self'. 'It's a minor procedure but it meant that he cannot go on a 27-hour flight to Australia,' he said. 'He's very disappointed that he can't fulfill the tour but it's nothing to be alarmed about. He's seeing his doctor now but he's still his lively self.' Animal lover: The broadcaster is pictured with an eagle during filming for his series The Life of Birds Close to nature: Sir David, seen meeting a three-month-old black rhino at a Kenyan wildlife reserve, has travelled the world making ground-breaking documentaries Expert: The natural history expert, seen interacting with a kangaroo at a zoo in Sydney, had been due to travel to Australia next week Tour: Sir David, 87, had been due to embark on a sold-out tour of Australia next week, which has been cancelled in light of his health issue Sir David, who had the surgery in London, is not thought to have had an existing heart condition. Pacemaker implantation involves inserting a small battery-operated device into a patient's chest, which emits regular electrical pulses that help to keep the heart beating regularly. The contractions of the heart muscle that pump blood around the body are triggered by electrical pulses. Should those natural pulses be disrupted for any reason, resulting in an abnormal heartbeat or arrhythmia, a pacemaker may be fitted. Common causes of arrhythmia include sick sinus syndrome, where the heart beats abnormally slowly, atrial fibrillation, where it beats abnormally fast, or a heart block, where the pulse that triggers the contraction of the heart muscle is either delayed or absent. Sir David is having a pacemaker implanted today The small metal box is attached to one or more wires - or pacing leads - that run to the heart. It contains a battery, pulse generator and tiny computer circuit that converts energy from the battery into electrical impulses which then flow down the wires and stimulate the heart to contract. The relatively straightforward implantation process is carried out under local anaesthetic, meaning the patient is awake throughout the procedure. Typically the generator is inserted beneath the skin near the collarbone, and attached to a wire that is guided through a blood vessel to the heart. The procedure, which usually lasts between 30 and 60 minutes, is one of the most common types of heart surgery, and most people are well enough to leave hospital the day after the surgery. News of the procedure came to light in a statement from the company promoting the Australian tour, entitled Sir David Attenborough: A Life On Earth. 'Sir David Attenborough is to undergo surgery in London today following advice from his cardiologist that he is in urgent need of a pacemaker,' Lateral Event Management said. It is with regret, therefore, that Lateral Events CEO Simon Baggs announced that the forthcoming sell-out tour of Australia, scheduled to begin in Brisbane next week, has been cancelled. Sir David expressed his extreme disappointment as he said he was very much looking forward to coming back to Australia and he hopes to reschedule his tour in the near future. The company said that it would discuss rescheduling the tour following the surgery. Meanwhile BBC director of television Danny Cohen sent a message of support to one of the corporation's most familiar frontmen, saying: 'We all wish Sir David a full and strong recovery.' Sir David, whose groundbreaking programmes have included Blue Planet and Frozen Planet, recently narrated and presented the hit BBC1 series Africa. He also presented a new BBC Radio 4 series, Tweet Of The Day, devoted to birdsong. The wildlife star said recently that he had no intention of doing less, saying: 'I've been broadcasting for 60 years. I don't want to slow down. Retirement would be so boring. Asked about his plans earlier this year, he said: 'I'm going to China to see some very interesting fossils. In 2012, I went to the Galapagos, to Africa, north America and Australia. 'I've no idea how many days I was away.' Beyond natural history, Sir David, who collected fossils as a child and gained a natural sciences degree from Cambridge, has also enjoyed an influential stint as a broadcast chief, introducing colour TV when he was controller of BBC2. Britain's best-known natural history film-maker, whose early programmes included Zoo Quest in 1954, recently underwent a knee replacement. He was knighted in 1985 and has also won a Royal Television Society Lifetime Achievement Award. To see the full interview by The Sydney Morning Herald click here