Every minute without CPR or defibrillation reduces a person's chance of surviving a cardiac arrest by about 10%, experts say.
A cyclist who had a cardiac arrest and "died" for a few moments before he was resuscitated by strangers has backed plans to improve access to defibrillators.
Alan Thompson, 61, from Swadlincote, Derbyshire, collapsed suddenly while out riding with his brother David six weeks ago.
Fortunately it happened in the small village of Smisby where a series of strangers immediately rushed to his aid and performed CPR, while one ran a few hundred yards to the village hall to grab a defibrillator.
Mr Thompson told Sky News: "I actually stopped breathing I lost all output from my heart, my extremities had started turning blue and I had actually passed away at that stage."
The shock from the defibrillator though brought him back to life and meant that paramedics and hospital staff in Derby could ensure he made a full recovery.
Today the NHS, The British Heart Foundation and Microsoft have announced a partnership that will map all of the UK's defibrillators to try to ensure they are used in more "out of hospital" cardiac arrests.
Currently defibrillators are used in just 3% of instances where people have heart attacks away from any medical care.
Tens of thousands of the devices have been installed in workplaces, villages, transport hubs and other public spaces, but despite some efforts to list defibrillators there is still no comprehensive national database.
The British Heart Foundation says the lack of such a network is significantly reducing people's chances of survival.
Chief executive of the charity Simon Gillespie said: "Every minute without CPR or defibrillation reduces a person's chance of surviving a cardiac arrest by around 10%.
"This innovative project will give every ambulance service immediate access to the location of defibrillators in their areas, so they can direct bystanders to their nearest life-saving device in the event of a cardiac arrest."
Mr Thompson welcomed the move and told Sky News: "Anything that improves access to these things is good, without it I would not be talking to you today.
"It's thanks to the people of Smisby who stepped in and saved me that I can carry on being a husband, a dad and a grandad.
"I owe them my life."
Mr Thompson has now had two stents fitted and is back home and has even resumed exercising.
In the coming months defibrillator owners or "guardians" will be invited to register their device online - starting in Scotland and the West Midlands. The network will then be rolled out across the UK.
Anthony Marsh, chief executive of the West Midlands Ambulance Service, said: "It's absolutely critical that we are able to direct cardiac arrest bystanders to their nearest defibrillator.
"This gives patients the best possible chance of receiving early defibrillation if it's required prior to the ambulance services arrival, which is proven to save lives."