Queen Elizabeth II's husband has undergone treatment for a blocked coronary artery, British royal officials said Friday.
Buckingham Palace said Prince Philip, 90, was taken from Sandringham, the queen's sprawling estate in rural Norfolk, to the cardiac unit at Papworth Hospital in Cambridge earlier Friday for "precautionary tests" after suffering chest pains.
The palace refused to confirm if Philip had suffered a heart attack, saying only that tests at the hospital showed a blocked coronary artery was causing Philip's discomfort.
"This was treated successfully by the minimally invasive procedure of coronary stenting," the palace said in a statement. "Prince Philip will remain in hospital under observation for a short period."
Doctors said Philip could have suffered a heart attack, but without more information it was impossible to know for sure.
Coronary stenting is standard procedure both to fend off a heart attack or save a patient already in the midst of one, said Dr. Allan Schwartz, chief of cardiology at New York-Presbyterian, Columbia University Medical Center.
"It is a big spectrum, there's no way of knowing what applies to him," Schwartz said. "Saying you're taken to the hospital with chest pain is like saying you're taken to the hospital with a gunshot wound. It could be a grazing shot that's not significant or it could be something that's serious. Either way with the right treatment, you're O.K."
Schwartz said Philip's trim figure and athleticism bode well for his recovery.
Dr. Jonathan Tobis, director of interventional cardiology at UCLA, said coronary stenting is much less invasive than surgery because it is typically done through a catheter method, inserting a balloon down a blocked artery, blowing it up to open the blockage, then putting in a stent to keep the artery wall open.
Tobis said that any procedure carries risks, but advances in coronary medicine over the past 30 years means the procedure can be done "remarkably safely _ even in people in their 90s."
"Nowadays, patients typically go home the next day," Tobis said.
A spokeswoman for the palace would not say if other members of the royal family were Philip, who is also known as the Duke of Edinburgh. She spoke on customary condition of anonymity. A hospital spokeswoman referred all calls to the palace.
Papworth Hospital's website says it is the U.K.'s largest specialist cardiothoracic hospital and the country's main heart and lung transplant center, offering services such as cardiology, respiratory medicine and cardiothoracic surgery and transplantation.
Philip had been at Sandringham since Monday for the royal family's Christmas festivities, Buckingham Palace said.
It was unclear how Philip's hospitalization would alter the royal family's plans for the weekend, which typically include a public appearance before church services and then a private family lunch.
Philip has been known to enjoy good health throughout his life and rarely misses royal engagements. Upon his 90th birthday in June, he announced plans to cut back his official duties.
He came down with a cold in October and canceled an overnight visit to Italy to recover. That illness came shortly after Philip accompanied the queen on a busy 11-day official royal tour of Australia.
Philip also spent three days in the hospital in 2008 for treatment of a chest infection after suffering a bad cold.
The colorful and often outspoken husband of Elizabeth has been a familiar figure at his wife's side for decades. He has championed numerous charities over the years, but is advising the ones he heads to start planning an orderly transition as he plots the end of his working life.
The royal family's traditional Christmas celebration will be followed by a year's worth of festivities to mark the queen's 60th year on the throne.
Elizabeth and Philip have been planning to mark the event with a series of tours throughout England to culminate with a celebration in London in early June that will include an unprecedented pageant on the River Thames with up to 1,000 boats taking part.
Most of the senior royals, including Prince William and his wife, now formally known as the Duchess of Cambridge, will be dispatched across the globe to help the aging monarch celebrate her Diamond Jubilee.
A member of the Greek royal family, Philip is descended from Danish and German royalty. He joined the Royal Navy in 1939 and saw active service throughout World War II.
Philip married Elizabeth in 1947, when she was still a princess. He gave up his naval career when she became queen.
Philip is a great-great-grandchild of Queen Victoria.
Cassandra Vinograd can be reached at http://twitter.com/CassVinograd