Greg Page knows he's one of the lucky ones.
In January last year the original Yellow Wiggle suffered a sudden cardiac arrest just after coming off-stage from a bushfire relief show at Castle Hill in Sydney.
Nurse Grace Jones was at the show and was able to give Page CPR and then use a defibrillator on him, which saved his life.
Page said most people don't have such a happy ending - 90 per cent of people who suffer a sudden cardiac arrest don't survive.
"One of the reasons there is such a high non-survival rate is because a lot of cardiac arrests happen in the home," Page said.
"About 80 per cent happen in the home and probably 40 to 60 per cent of those are what we call unwitnessed cardiac arrests.
"So someone collapses and nobody knows how much time has passed before they're found. Because we don't know how long they've been gone for, we don't know how successful the resuscitation attempt is going to be because you only have limited time to respond."
One thing he says can help save someone's life is called the Chain of Survival, which is call, push, shock. Call Triple 0, start CPR and use a defibrillator.
"Those three simple steps are really what can increase someone's chances of surviving a sudden cardiac arrest drastically," he says.
Just pushing on the chest of someone who's not responding, not breathing, will give that person at chance at surviving. If they do nothing that person will have no chance.Greg Page on how to save the life of someone suffering sudden cardiac arrest
He acknowledges there is a sense of fear around starting CPR on someone, because Page himself felt the same way before his own cardiac arrest.
"If the shoe had been on the other foot and I had been a bystander I probably would have thought that I shouldn't try it because I'm not trained, I'm not qualified to do it," he said.
"I would have not done anything. What I've learnt since then is you don't have to be trained or qualified to try and do CPR on someone to save their life because any attempt at resuscitation is better than no attempt."
As he says, if someone goes into sudden cardiac arrest and no-one does anything, the only guaranteed outcome is that person will die.
Since his cardiac arrest, Page has wanted to make the most of his second chance, starting the Heart of the Nation charity to raise awareness of sudden cardiac arrest and what to do, as well as being involved in a televised CPR class on Saturday afternoon.
"That's really the motivation behind putting together the world's largest CPR class," he said.
"The more people we can get tuned in to watch this, the more people we can get familiar with CPR and the fact that you don't have to have a formal qualification to do it to save someone's life.
"Watching the show on Saturday will empower a lot of people to understand just pushing on the chest of someone who's not responding, not breathing, will give that person at chance at surviving. If they do nothing that person will have no chance."
As well as providing instruction on delivering CPR (people are advised to practice on a pillow), the show will also include an overview of sudden cardiac arrest as well as stories of the survivors and those of families who have lost someone.
"That's really the tragedy because 90 per cent of people don't survive," he said.
"So for 90 per cent of people who have a connection to sudden cardiac arrest it's because of a tragic outcome. We want to try and change that. We want to make sure there's more survivors, so the more people that know about the Chain of Survival and how to do CPR the more chance we'll have a greater number of survivors."