The man, who has not been named, was half-way through his meal at the aptly named Heart Attack Grill, when he began to feel chest pains.
Paramedics rushed to the scene and wheeled the diner, believed to be in his 40s, into an ambulance.
The infamous eatery, which is famous for using the phrase, ‘A taste worth dying for’, has previously come under fire in the US for promoting unhealthy eating.
As the man collapsed, tourists were taking photos of him, thinking it was a publicity stunt.
But restaurant owner Jon Basso, said it was a genuine incident: “The gentleman could barely talk. He was sweating, suffering.
“Even with our own morbid sense of humour, we would never pull a stunt like that.”
The burger in question is a gut-busting favourite with hungry customers, which contains three slabs of meat, 12 slices of bacon and is usually accompanied by ‘Flatliner Fries’.
Last year Heart Attack Grill ran a promotion offering a free meal to any customers, known to staff as ‘patients’, weighing over 25 stone.
A controversial advert run by the company last year caused outrage promoting the restaurant’s fat-tastic food, including the Quadruple Bypass Burger.
It featured the line: “In some cases mild death may occur.”
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