Coronation Street star Bill Tarmey, alias Jack Duckworth, was due to undergo a heart bypass operation today, a spokeswoman for the soap said.
The 61-year-old actor was due to have the six-hour operation at the Alexandra Hospital in Cheadle, Cheshire.
It will the second heart bypass that Tarmey, a heavy smoker, has undergone. He had a successful quadruple bypass 15 years ago.
Tarmey has been plagued by ill-health, suffering a heart attack at the age of 35 and a stroke the following year.
A Coronation Street spokeswoman said the operation was scheduled to begin this afternoon.
"Like most patients who have undergone coronary surgery, William will remain in the hospital’s intensive care ward for the first three days after his operation.
"Both William and his wife Ali have expressly asked that the family’s privacy is respected at this time," she said.
Tarmey has been temporarily written out of the soap until he is well enough to return to work.
His character in the Street also underwent a triple heart bypass operation after suffering bouts of angina.
The actor, who plays one of the soap’s best-loved characters, has refused to give up smoking despite his heart problems.
"I could make it easier on myself. I could give up smoking. I could go and sit in a rocking chair.
"But that wouldn’t be me. That would kill me sooner than the old ticker would," he told a newspaper last year.
"If I die tomorrow they will have to prise the smile off my face because I’ve had such a good life."