A technique to resuscitate patients has saved the lives of 34 extra cardiac arrest sufferers in the eastern region.
An audit by the East Anglian Ambulance Service of those patients whose hearts were capable of being restarted showed a 26% improvement in resuscitation.
In 2005, 84 patients had their hearts restarted compared with 50 in 2004.
The treatment pioneered in America and introduced a year ago gives chest compressions before giving the heart an electric shock with a defibrillator.
The success rate of those treated was prior to their arrival at hospital.
Previously guidelines indicated giving an electric shock as early as possible.
Now ambulance crews are advised to give two minutes of chest compressions, if they arrive more than four minutes after the cardiac arrest occurred, prior to using a defibrillator.
For those patients where the paramedic witnesses the cardiac arrest immediate defibrillation is still indicated.
The East Anglian Ambulance Service covers Cambridgeshire, Norfolk and Suffolk