Rome, June 21 - The cause of death is expected to be released following an autopsy on Friday for Emmy award winning actor James Gandolfini who died in a Rome hotel while on a working vacation with his family. Gandolfini, 51, is believed to have died from a heart attack. He was taken to a hospital in the capital Wednesday after collapsing at his hotel, the Boscolo Exedra, around 10 pm, sources said. Attempts to resuscitate him by both ambulance workers and hospital staff failed. Following the autopsy, the United States Embassy in Rome is expected to issue a death certificate so his body can be returned to the US. Born in New Jersey to Italian-American parents, the actor was scheduled to appear at the Taormina Film Fest in Sicily next weekend with Italian director Gabriele Muccino, known internationally for his film The Pursuit of Happyness. "It is with immense sorrow that we report our client, James Gandolfini, passed away today while on holiday in Rome, Italy," managers Mark Armstrong and Nancy Sanders said in a joint statement. "Our hearts are shattered and we will miss him deeply. He and his family were part of our family for many years and we are all grieving."