By Alasdair Glennie PUBLISHED: 05:29 EST, 4 June 2013 | UPDATED: 19:58 EST, 4 June 2013 Sir David Attenborough was admitted to hospital for urgent heart surgery yesterday. The 87-year-old naturalist was fitted with a pacemaker, which is normally used to correct an abnormal heartbeat. Doctors were said to be satisfied with his progress, although he was forced to cancel a sold-out speaking tour of Australia, due to start next week. Scroll down for video Surgery: The veteran wildlife presenter, seen on the Jonathan Ross Show in February this year, is undergoing heart surgery today A spokesman said his cardiologist had told him he needed a pacemaker fitted urgently and added: ‘Obviously after that you can’t take a long-haul flight.’
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Presenter, 87, fitted with a pacemaker today on urgent advice of cardiologist
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Sir David had been due to embark on sold-out tour of Australia next week
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Spokesman said doctors believe broadcaster is 'doing well' after operation
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To see the full interview by The Sydney Morning Herald click here
David Attenborough
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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 @placeholder is having a pacemaker implanted today