Actor James Gandolfini suffered cardiac arrest in Rome and subsequently died in a hospital in the Italian capital, a Roman doctor confirmed.
Reports suggest it was the Sopranos star's 13-year-old son, Michael, who found him after the heart attack in a hotel room.
The doctor in charge of the emergency department at the hospital where the actor was admitted, Claudio Modini, told the Los Angeles Times that Gandolfini, 51, was already in cardiac arrest when he arrived at Policlinico Umberto I Hospital Wednesday night.
"He was put under resuscitation treatment for 40 minutes, but the emergency staff failed to restart his heart, and at 23:00, he was pronounced deceased."
In according with Italian law, an autopsy will be conducted within 24 hours of his death.
Antonio D'Amore, manager of the Boscolo Excedra hotel, told NBC it was Michael — who was on a special celebration trip with his father, due to be honored at a film festival in Sicily — who found his father.
Gandolfini had turned the trip into a celebration for Michael, who had just graduated from junior high school and won a soccer championship.
When Michael called for help after discovering his father collapsed in a bathroom, D'Amore told NBC, hotel workers tried to resuscitate the actor, and he was still alive when the ambulance arrived.
The US Embassy in Rome said it would provide a death certificate and help prepare the body for return to America within seven days.
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