"The procedure is significant but I am confident that we will get a good result. I'm in good spirits and progressing satisfactorily and thank everybody for their good wishes.''
Newstalk ZB station manager Dallas Gurney said Mr Holmes was having a routine heart procedure to remedy a long-term complaint.
The broadcaster was in good spirits and is expected to return to work within weeks, Mr Gurney said.
Mr Holmes became a campaigner for prostate cancer awareness after beating the disease more than a decade ago.
He was admitted to Hawke's Bay Hospital after falling ill at his home at Poukawa, near Hastings, in January.
However, he recovered quickly from the illness and returned to work the following week.
- Herald Online staff