The survival rate of out-of-hospital cardiac arrest victims across the world has not improved since the 1950s, a new report has found.
The University of Michigan Health System report, which analysed data between January 1950 and August 2008, said 7.6% of victims survive if they have a cardiac arrest when they are not in hospital.
The 'Circulation: Cardiovascular Quality and Outcomes' report said the trend is worrying because of the enormous spend on heart research, new emergency care protocols that have been put in place and the advent of new drugs and devices such as defibrillators.
U-M Health System emergency medicine physician and lead author Comilla Sasson said a number of factors a vital in savings lives.
"Our study shows that patients with a heart rhythm that can be shocked, or who have bystander CPR or a pulse restored at the scene have a much greater chance of survival," said Sasson.
Researchers also found victims with ventricular fibrillation are more likely to survive cardiac arrests.
It also said the strongest predictor of survival was a return of spontaneous circulation, meaning a pulse was restored at the scene.