‘GOOD Day New York” anchor Jim Ryan will undergo triple-bypass heart surgery today and will be off the morning show indefinitely.

Ryan, 61, was experiencing chest pains on Wednesday and went to the hospital, where it was determined he needed the heart surgery. He was off the air yesterday.

Ryan’s surgery will be performed by Dr. O. Wayne Isom – the same doctor who performed David Letterman’s quintuple-bypass heart surgery in January 2000.

Isom is chairman of cardiothoracic surgery at the Weill Cornell Center of New York.

A Fox spokeswoman said Ryan is expected to spend six days in the hospital. Ryan’s place at the “GDNY” anchor desk will be filled by a rotating roster of guest hosts over the next few weeks.

Ryan, who’s been with “GDNY” since the show’s 1988 debut, recently signed a two-year deal to continue with the popular morning show. “GDNY” airs weekdays from 7 to 9 a.m. on Ch. 5.