PRINCE Philip has undergone tests on his heart after doctors feared for his health.
The Duke of Edinburgh is at Aberdeen Royal Infirmary, Scotland, where he was taken on Wednesday (15.08.12) as a "precautionary measure" after suffering from a recurrence of a bladder infection, and medics have done a series of tests to make sure he will be able to recover.
A royal aide told the Daily Star newspaper: "He was given top-to-toe tests including heart checks because they were concerned.
"They were worried about his ticker and wanted to be sure.
"That's why they are taking their time to give him a thorough examination in hospital so they can deal with any problems."
The 91-year-old prince has been told to rest by doctors and has not been receiving visitors while he recovers, although members of the Royal family are staying nearby.
On Friday (17.08.12) doctors said the duke was responding well to treatment, and in touch with his loved ones by telephone.
In June, Philip was taken ill after spending hours on a ceremonial barge in rain and a cold wind as part of a flotilla of 1,000 vessels on the River Thames to mark the queen's Diamond Jubilee.
Royal aides said he was treated with antibiotics and made good progress before being released six days later.
In December he had a heart operation where surgeons cleared a blocked coronary artery and inserted a stent to ease the problem.
The queen and royal aides are now deciding whether her son Charles or grandson, Prince William, should step in to accompany her on royal engagements.
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