Sir Michael Palin is to undergo heart surgery later this year.
The comedian and Monty Python member will have the procedure to fix his mitral valve, a small flap that prevents blood from flowing in the wrong direction around the heart.
He discovered the problem five years ago and has revealed that it didn’t affect his fitness until earlier this year.
“I shall be undergoing surgery in September and should be back to normal, or rather better than normal, within three months,” he wrote on his website.
“I have felt my heart having to work harder and have been advised it’s time to have the valve repaired.”
Palin, who was knighted in June, has cancelled a book tour scheduled for October.
The sometime travel presenter was due to promote North Korea Journal, which comes after his 2018 Channel 5 documentary about his experience in the country where tourism is tightly controlled.
Publisher Penguin has promised that all tickets to the tour will be refunded.
In 1989, the actor won a Bafa for his supporting role in film comedy A Fish Called Wanda.
