"Apparently my head fell backwards and my eyes rolled into the back of my head and I just slumped on to the steering wheel," she said.

"The poor kids were screaming at me from the back seat, trying to wake me up, but I have absolutely no recollection of it happening."

Though Ms Mitchell didn't know it at the time, she had just suffered ventricular fibrillation – an often lethal heart rhythm disturbance.

Unfortunately this is not an uncommon occurrence, with heart disease being the number one killer of Australian women.

In 2012 there were 221 heart disease-related deaths in the ACT, 99 of these cases were women.

At least 90 per cent of Australian women have at least one risk factor for heart disease, including high cholesterol, an inactive lifestyle, or an unhealthy diet.

On Thursday the Heart Foundation is painting the town red with its Go Red for Women Day, to raise awareness of the prevalence of heart disease in women.

The foundation began a month-long Go Red for Women campaign in 2010 after a survey revealed only 20 percent of women were aware heart disease was their biggest killer, but according to fundraising manager Ann Ronning this is the first time the foundation has dedicated a singular day to the campaign.

"There are a lot of great charities and causes, but we really wanted our message to cut through" Ms Ronning said.

"We wanted to focus on one day where we could really shine and the community could get behind us.

"This year it's all guns blazing."

People all around Australia wear red in support of the campaign in which they can donate directly to the cause or else host their own event with friends and family to collect donations.

Go Red for Women Day has received much support from the local community, with walking group the Groovy Grannies supporting the campaign, as well as the Raiders cheerleading team, The Emeralds.

Heart Foundation board member and clinical director of medicine at Canberra Hospital Dr Walter Abhayaratna said there are a lot of myths surrounding heart disease, but the foundation was putting a lot of effort into increasing women's awareness of their risk.

"People stereotype heart attacks to men but I think it's really important that women realise heart attacks aren't just a male phenomenon," Mr Abhayaratna said.

Ms Mitchell said it was a "real shock" to discover she could have died.

"If women have any worries they shouldn't put off getting checked and think it'll be ok, they should do something about it."

Last year the Go Red for Women campaign raised $2500 in the ACT, but this year the foundation hopes to reach its target of $15,000.