Japan's Emperor Akihito Has Open-Heart Surgery TOKYO - Emperor Akihito of Japan was in stable condition after undergoing open-heart surgery and could leave the hospital within two weeks, doctors said Saturday. The emperor's lead physician, Dr. Ichiro Kanazawa, said the procedure, performed at the University of Tokyo Hospital, replaced an obstructed artery. It was unclear when the emperor, 78, would be able to resume his official duties, but Dr. Kanazawa said his age should be taken into consideration. He added that he expected the emperor to once again be able to enjoy his favorite sport of tennis. Emperor Akihito's son, Crown Prince Naruhito, temporarily assumed the emperor's largely symbolic constitutional duties after his father went into the hospital late last week.