Denmark's Queen Margrethe has undergone an angioplasty procedure after being admitted to hospital this week for chest pain, the palace said in a statement on Friday. ADVERTISEMENT ADVERTISEMENT The court said the queen had "a balloon dilation of a coronary artery" at Copenhagen's main hospital Rigshospitalet, where she was admitted on Thursday. The queen, who has been a chain smoker for much of her life, was in "good condition" but would remain in hospital for "a few more days," the palace said.