Governor General Adrienne Clarkson, 66, was taken to a Toronto hospital Friday, to undergo an operation this weekend to insert a pacemaker.

Pacemakers are small battery-powered devices that are implanted in the body. Electrical impulses stimulate the heart to contract and thus to pump blood throughout the body.

"She went in and just had a routine appointment today and doctors felt she had to be admitted," CTV's Rosemary Thompson told CTV Newsnet.

Clarkson has decided to suspend all of her activities.

"She's been very active," Thompson said. "We saw her just a few days ago at Canada Day, in front of tens of thousands of Canadians on Parliament Hill."

Clarkson's press secretary Randy Mylyk told Thompson that the Governor General is "absolutely fine."

"Obviously she's taking it very easy right now," said Thompson. Clarkson is known to keep a hectic pace, but "she's going to have to be a little bit quieter over the next few weeks."

In 2004, Prime Minister Paul Martin asked Clarkson to remain as Canada's Governor General for another year.

The Liberals had just won a minority government, and Martin likely wanted an experienced Governor General in place should the Liberals lose a confidence vote, which would collapse the government.

Clarkson became a Governor General in 1999. A Governor General traditionally stays in office for about five years, although six-year terms are not unusual.

Roland Michener served for almost seven years, from 1967 to 1974. Georges Vanier, who preceded Michener, died in office in 1967 after 7˝ years in the post. Both presided over minority governments.

Clarkson was born in 1939 in Hong Kong, and came to Canada with her family as a refugee during the Second World War.

She was later awarded a B.A. and M.A. in English Literature from the University of Toronto, and became a great advocate for Canadian arts and culture.

From 1987 to 1988 Clarkson was the president and publisher of McClelland & Stewart, and she has also been an accomplished journalist and writer.

Clarkson has worked in film and television as well, and won several awards for her work.

She was appointed an Officer of the Order of Canada in 1992.