WORLDWIDE COVERAGE: Beloved star ignored doctor’s warning before fateful trip to Italy, and then he checked into a hotel that wasn’t equipped with a defibrillator that could have saved his life!

In an exhaustive investigation into “The Sopranos” star’s tragic final hours, The ENQUIRER has also learned the 51-year-old actor complained of feeling ill shortly before suffering his fatal heart attack.

Sources say Gandolfini lay on the bathroom floor of his hotel suite for more than 30 minutes before medical help arrived. But by then, it was too late. The man the world knew as TV’s greatest mob boss, Tony Soprano, was dead.

Medical sources say Gandolfini’s biggest mistake was booking a $671-a-night suite at Rome’s posh Boscolo Exedra hotel, which didn’t have a $1,200 defibrillator that could have jump-started his heart.

But insiders say the 6-foot-1 actor – who’s publicly admitted to battling booze and drug addictions – had also packed on 40 pounds, ballooning to nearly 300.

Before leaving his home in Los Angeles, Gandolfini had been warned that his heart could give out at any moment.

 “Only hours before James jetted off to Rome, he struggled into a chiropractor’s office,” a close friend of the actor told The ENQUIRER.

“His weight had soared, he was drinking again, and his back was under stress. He was in terrible pain and dreaded the long flight overseas. The chi­ropractor told James point-blank that he had to stop drinking and go on a serious diet – or else he’d have a heart attack. James didn’t listen – and that’s exactly what happened!”

The ENQUIRER has retraced Gandolfini’s steps in Rome, where he planned to spend three days sightseeing with his son from his first marriage, 13-year-old Michael, before heading to the Taormina Film Festival in Sicily.

His sister Leta Gandolfini, 65, joined them after a work trip in France. But second wife Deborah Lin and their 8-month-old daughter Liliana remained in Los Angeles.

ON THEIR FIRST NIGHT IN THE ETERNAL CITY, June 18, Gandolfini and his son dined at the Sabatini restaurant near the Tiber River. The three-time Emmy winner gorged on a large platter of pasta and tomato sauce, and drank Campari and soda and red wine.

They returned to their hotel, where Gandolfini spent over an hour in the bar. He chatted with pa­trons and staff members, and drank several glasses of red wine before heading to his room, said a hotel source.

The next day, Gandolfini and his son did some sightseeing in sweltering 100-degree heat. At around 7 p.m., they sat down at their hotel’s out­door restaurant Tazio. Although Gandolfini didn’t realize it, the meal was destined to be his last supper – and it was massive!

The actor consumed at least eight alcoholic drinks – four shots of rum, two beers and two pina coladas, sources say.

He also ate two large orders of fatty pate foie gras, or duck liver, on toast, plus two orders of fried King prawns and squid in a greasy mayonnaise-chili sauce, along with a basket of rolls smeared with a soft cheese and cherries.

“I was shocked. He ate like four men!” a source at the restaurant told The ENQUIRER.

“He looked tired, but he was laughing with other guests and having a great time.”

Gandolfini’s “killer meal” brought his calorie count to 5,000 for the day, according to experts, and The ENQUIRER has learned that shortly after returning to his hotel room with his son, he felt ill.

“James complained to Michael of not feeling well and excused himself to go to the bathroom,” family friend Robert Sottolano – who, along with his wife, lives near the actor’s sister Leta in Westwood, N.J. – told The ENQUIRER.

“When he didn’t come out, Michael tried to check on him. James was having the heart attack, but Michael never realized it.”

Gandolfini was in the bathroom for 30 minutes before Michael began pounding on the door, Sottolano said. When his father didn’t respond, Michael bolted out of the room and went down to the lobby, shouting for help, according to concierge Pasquale Benediccio.

“The boy was distraught – in a complete panic,” Benediccio told The ENQUIRER.

“Security personnel rushed upstairs and used a screwdriver to open the lock on the bathroom door. They found Gandolfini on the floor in front of the toilet, unconscious, and immediately called the ambulance.”

The ambulance arrived within minutes and it took six hotel security men to get the hefty Gandolfini onto a gurney and down the elevator. But The ENQUIRER has learned that it was already too late. Sadly, “The Sopranos” star was already dead.

“There was no hope to revive him,” Livio De Angelis, director of ambulance services in Rome, who reviewed the ambulance drivers’ report, told The ENQUIRER.

“We got a Code Red call, which is the most urgent, at about 10 p.m. We were told that the patient was not breathing and not conscious.

“Ambulance No. 686 from Via Treviso was nearest and arrived at the hotel in eight minutes at the most. We even sent a second ambulance that arrived two minutes after the first one.

“When the ambulance crew arrived, Gandolfini’s son was not to be seen, but his sister was standing outside the room. She shouted, ‘Come in! Come in! Quickly!’

“Hotel personnel had been doing CPR, and our drivers hooked up a defibrillator immediately. But the patient had already flat-lined. He had no systolic pressure, and the defibrillator could not be used effectively.

“The crew began to use an ambu-bag to force oxygen into his lungs and continued heart massage all the way to the hospital. But he was long dead. There was no heart activity.”

Gandolfini’s sister and son stood in the emergen­cy room while doctors tried to save him, he added.

“It was quite obvious that they were distraught,” said De Angelis.

“We had no idea that he was a famous man – only an American tourist who was a very large man, and apparently had suffered a fatal heart attack.”

Gandolfini was pronounced dead at Poli­clinico Umberto hospital by Dr. Claudio Modini at 11:00 p.m.

But The ENQUIRER has learned that if his hotel had been equipped with a defibrillator, which is standard equipment for many lux­ury hotels in Rome, Gandolfini may have been saved.

“HE ABSOLUTELY MAY HAVE sur­vived if hotel personnel had used an AED (Automated External Defibril­lator) when they found him,” Dr. Matthew Budoff, who has not treated Gandolfini but is an associate professor of medicine at the David Geffen School of Medicine UCLA and a renowned cardiologist, told The ENQUIRER.

“For each minute that passes following a heart attack, the survival rates drop by 10 percent. So if five minutes pass without assistance by the AED, his survival rate is 50 percent. If 10 minutes go by, the risk of dying is 100 percent. There is no question that had they used an AED when they first found him, his chances of survival would have been greatly improved.”

The initial autopsy report confirmed that Gandolfini had suffered a fatal heart attack.

In a final insult to the actor’s dignity, The ENQUIRER has learned that his luxury Soarway Diver Seal watch, which he designed with German watchmaker Michael Kobold, had been stolen.

The actor was wearing the pricey timepiece when he fell ill, but it dis­appeared somewhere between the hotel bathroom and the morgue, sources say.

“Police in Rome are investigating the case,” a source told The ENQUIRER.

“Stealing a watch from a dead man is a ter­rible thing. Whoever did should hang for it!”