Prince Philip undergoes heart surgery for pre-existing condition

Prince Philip has undergone a surgical procedure for a pre-existing heart condition, Buckingham Palace has confirmed.

In a statement, the palace said the Duke of Edinburgh's surgery, performed at London's St Bartholomew's Hospital on Wednesday, had been successful.

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"His Royal Highness will remain in hospital for treatment, rest and recuperation for a number of days," the statement added.

The Queen's husband, 99, has been in hospital since February 16.

He was originally admitted to King Edward VII Hospital as a "precautionary measure", the palace confirmed in a statement, and walked into the facility unaided.

Earlier this week he was transferred to St Bartholomew's, a facility specialising in cardiac care, located about five kilometres away, via ambulance.

A statement explained he would undergo "testing and observation for a pre-existing heart condition" as well as an infection.

"The Duke remains comfortable and is responding to treatment but is expected to remain in hospital until at least the end of the week," it said.

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Prince Charles visited his father in hospital on February 20, travelling to London from his home in Gloucestershire.

Prince Philip has received treatment for various health conditions over the years, including a blocked coronary artery in 2011 after which he had a stent fitted.

He also had bladder infection in 2012 and exploratory surgery on his abdomen in June 2013.

This current hospital stint has been his longest; he spent 11 days in hospital in 2013.

Since retiring from public life in 2017, Philip has made few public appearances.

He has spent most of the COVID-19 pandemic in isolation with Queen Elizabeth at Windsor Castle, making a special official appearance in July 2020 for a virtual handing-over of his role as Colonel-in-Chief of The Rifles.

The duke also attended the wedding of his granddaughter Princess Beatrice and Edoardo Mapelli Mozzi in Windsor that same month, along with Her Majesty.