The palace says the 99-year-old Duke of Edinburgh, the husband of Queen Elizabeth II, “underwent a successful procedure for a pre-existing heart condition at St Bartholomew''s Hospital.”It said he is expected to remain in the hospital for "treatment, rest and recuperation for a number of days.”Philip, 99, has been hospitalized since being admitted to King Edward VII''s Hospital in London on Feb. 16, where he was treated for an infection.

On Monday he was transferred to a specialized cardiac care hospital, St. Bartholomew's.