More than 2000 people are treated every year in New Zealand for sudden cardiac arrest.
Survival is largely dependent on effective CPR and most importantly access to an automated external defibrillator (AED).
Dangerous cardiac arrests can happen anywhere - often without warning.
Red Cross national products manager Marcus Bird told Newshub just 14 percent of those who experience a cardiac arrest in the community survive.
"And those who do survive is because they have an AED nearby and someone who can do CPR," he says.
With 2000 Kiwis experiencing the life-threatening event each year, chances are one day you'll need to know how to use an AED.
"Modern AEDs are really easy to use," says Bird.
"They're fully automatic, the results coach takes you through every step of what to do."
AEDs apply an electric shock to the heart to get it beating - access to one is often the difference between life and death. It's something Lisa Young knows all too well.
"I was up on stage in front of 250 footballers and halfway through the speech I just fell off the stage," she told Newshub.
She suffered a life-threatening sudden cardiac arrest.
"They pretty quickly figured out I wasn't breathing so started CPR. They called the bar staff at the Woolston club and the bar staff ran and got the AED."
Kiwis are encouraged to download the AED app which within seconds will show you a nearby AED station.
They are so vital to survival, Countdown is the latest big company to install one in every single store - and crucially even in those that are remote.
Countdown's health and safety manager Kiri Hannifin says it's vital.
"In some small towns we may be the main business in the town and we operate nearly every day except Christmas."
It's peace of mind to help prevent one of our biggest killers.
