File photo dated 17/10/2011 of Queen Elizabeth II and the Duke of Edinburgh (centre) listening to a speech by King Constantine of the Hellenes, during the opening ceremony of the Round Square International Conference at Wellington College, Crowthorne, Berkshire. The Duke was taken from Sandringham to the cardiothoracic unit at Papworth Hospital in Cambridge this evening for "precautionary tests" after suffering chest pains, a spokeswoman for Buckingham Palace said.