More than 1,500 Scots died last year after suffering a cardiac arrest out-with hospital, the Scottish Government said.
Its new initiative aims to cut that figure by getting 970 defibrillators into communities across the country - one for each NHS dental practice.
The easy-to-use machines will also be mapped on to the Scottish Ambulance Service control system to help call handlers direct people to the nearest practice while an ambulance is on its way.
A defibrillator can be used by anyone to deliver an electric shock to the chest to restore a person's heart to a normal rhythm after a cardiac arrest.
Currently, just five per cent of people who have a heart attack in the community survive and every minute of delay cuts their chances, ministers said.
Public Health Minister Michael Matheson said: "Every second counts when someone's heart goes into cardiac arrest and having access to a defibrillator can mean the difference between life and death.
"As these machines are becoming easier to use it is only right that the public have more access to its life-saving potential in any public place.
"There are almost 1,000 NHS dental practices in the centre of Scottish communities. By giving them this equipment we are providing 1,000 more chances to save a life.
"I believe that this investment will save many more lives."
The machines are expected to be in place by the end of August.
Any dental practice which has already bought a defibrillator will be compensated.