TORONTO -- Canadian folk singer-songwriter Ian Tyson has cancelled his appearance at an upcoming concert after an "unexpected and serious medical situation."

A representative for the 84-year-old Victoria native, who penned "Four Strong Winds" as one half of Ian & Sylvia, said he was admitted to hospital on Monday after recent issues with his heart rhythm.

Paul Mascioli, Tyson's manager, said Friday he expects the musician will undergo a medical procedure in the coming days before he returns to his ranch to recuperate.

He's cancelled all appearances in the meantime and notified fans of the decision.

"I'm having some heart problems and the doctors are looking after me," Tyson said in an email to ticketholders for an Aug. 25 concert in Drumheller, Alta., where he was to share the bill with Corb Lund.

"Thanks for everyone's thoughts and see you soon."

Tyson, who was named to the Order of Canada in 1994, has faced heart problems in the past. He underwent surgery at Calgary's Foothills Hospital to replace an aortic valve three years ago.

Mascioli said the musician has a determination and strong will that he expects will pull him through.

"I've represented him for over 30 years and he's had a few hiccups before and overcome them," he said. "I can't see why he wouldn't do this one too."

Lund plans to go forward with the Alberta concert where Tyson was originally slated to appear.

"I'm disappointed that Ian and I won't be able to share the stage at such an amazing venue so close to where we both call home," he wrote on Facebook.

"However, I will be honouring the intended spirit of the evening by continuing on with the show solo, and performing many of the songs -- Ian's and my own -- that we had planned to sing together."

Lund said information about ticket purchases and refunds are available through email at or by calling 403-823-2001.

Tyson's storied career began in the coffee houses of Toronto's Yorkville neighbourhood, where he met Sylvia Fricker.

The two formed a relationship both on and off the stage, leading their breakthrough album, 1964's "Four Strong Winds."

Their careers grew apart and the couple divorced in 1975.

Tyson's self-released 1987 album, "Cowboyography," became a surprising word-of-mouth hit and rejuvenated his touring career in Canada and the U.S.

The same year he won a Juno Award for country male vocalist and five years later he was inducted into the Juno Hall of Fame alongside Sylvia Tyson. He also won a Governor General's Performance Arts Award in 2003, the Canadian Music Hall of Fame and the Canadian Country Music Hall of Fame.