Employees and customers congregate at the bar of Satin Dolls, which stood in as the Bada Bing Club filmed in the TV show "The Sopranos", in Lodi, New Jersey, June 20, 2013. [Photo/Agencies]

Doctors at a Rome hospital battled for 40 minutes to try to save the life of James Gandolfini, best known for his Emmy-winning role as a mob boss in the TV series "The Sopranos," before pronouncing him dead, the emergency room chief said on Thursday.

Gandolfini, 51, whose performance as Tony Soprano made him a household name and help usher in a new era of American television drama, was vacationing in Rome and had been scheduled to attend the closing of the Taormina Film Festival in Sicily on Saturday.

He was taken from his Rome hotel to the city's Umberto I hospital late on Wednesday, according to a hospital spokesperson.

The actor's 13-year-old son, Michael, had found him collapsed in the bathroom of his Rome hotel room, Gandolfini's manager, Mark Armstrong, said in an email.

"The resuscitation maneuvers, including heart massage, etc., continued for 40 minutes and then, seeing no electric activity from the heart, this was interrupted and we declared James dead," Claudio Modini, the emergency room chief, told Reuters.

"The patient was considered dead on arrival, and for that reason an autopsy has been requested to be carried out by a pathologist, as is normal procedure in our country."

The autopsy has been scheduled for Friday morning.

Since "The Sopranos" ended its six-season run in June 2007, Gandolfini appeared in a number of big-screen roles, including the crime drama "Killing Them Softly" and "Zero Dark Thirty," a film about the hunt for Osama bin Laden.

Academy Award winner Kathryn Bigelow, who directed Gandolfini in the film, said she was devastated by the news of his death.

"James was such an enormous talent, and an even greater spirit. I will be forever grateful for the privilege of working with him, and shall cherish his memories always," she said in a statement.

At the time of his death, Gandolfini had been working on an upcoming HBO series, "Criminal Justice," and had two motion pictures due out next year

Actress Edie Falco, who played Tony Soprano's long-suffering wife, Carmela, in "The Sopranos," said her co-star was a man of "tremendous depth and sensitivity."

"I consider myself very lucky to have spent 10 years as his close colleague," she said.

Apart from Michael, his son with his first wife whom he divorced in 2002, Gandolfini is survived by wife, Deborah Lin, a model he married in 2008, and baby daughter Liliana, born last year.

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