AP

Elvis Presley, who died in 1977, may have been killed by his chronic constipation, according to his longtime friend and physician, Dr. George Nichopoulos.

It wasn't a heart condition that killed the King of Rock 'n' Roll, it was chronic constipation.

This is the new theory of Elvis Presley's longtime friend Dr. George Nichopoulos, Fox News reported on Wednesday.

"We weren't sure [of the exact cause of death] so I continued to do some research," said Nichopoulos, who was also the personal physician to the legendary singer. "I had some doctors call me from different places and different med schools that were doing research on constipation and different problems you can get into with it."

Nichopoulos, who was with Elvis when he died, included his theory about the icon's death in his book, "The King and Dr. Nick."

According to his autopsy, Nichopoulos said, Elvis' colon was 5 to 6 inches in diameter, nearly twice the size of the average person. It was also 8 to 9 feet long, compared with the normal 4 to 5 feet.

"We didn't realize until the autopsy that his constipation was as bad," he said, noting that when he died there was waste in his colon that was several months old.

"We found stool in his colon which had been there for four or five months because of the poor motility of the bowel," Nichopoulos said.

Elvis, he told Fox News, suffered from a hereditary condition called bowel paralysis, which made it difficult for him to go to the bathroom.

"He would get embarrassed," he said. "He'd have accidents onstage. He'd have to change clothes and come back because of the way we were trying to treat his constipation."

Although they were aware of the problem in the early 1970s, Elvis was reluctant to treat it. At the time, it would have required a procedure called a colostomy, which would involve removing part of the colon.

"He thought he was really a man's man and he wasn't going to let something like this he thought that this was a sign of weakness and he wasn't going to be weak," Nichopoulos said.

However, he said if they had treated it Elvis could very well still be alive today.

"If they had done the colostomy then, he'd probably still be here," Nichopoulos said.

msheridan@nydailynews.com