Receive a message. Provide CPR. Save someone's life.
Heartsavers is an initiative to improve the survival rates of cardiac arrests that occur out of hospital. There are 60,000 every year, where less than one in ten survive.  There are up to 175,000 heart attacks in the UK each year, a rate of one every three minutes. 
We aim to use mobile technology to send messages to CPR-trained individuals to alert them when there's is a cardiac arrest sufferer nearby.
Heartsavers will launch in the UK, in selected cities, initially.
1. Sign up and provide the date of your last CPR training. We will send alerts only to people trained in CPR in the last three years. If you would like to receive training, see a list of training providers below.
2. Run our web application or download the mobile application for Android or iOS. This will note your location.
3. We will work with emergency services so that when a suspected cardiac arrest is nearby, you will be alerted to the site via your mobile phone. We will provide a map and description of the address.
4. Provide CPR until an ambulance arrives.
Both you and the emergency services are alerted simultaneously. If you arrive before the ambulance, introduce yourself as CPR-trained and begin resuscitation. When the ambulance arrives, let them take over and briefly inform them what you've done and observed. If you arrive after the emergency services, allow them to take care of the patient.
To be part of the initiative, you must be over 18 and have completed CPR training in the last three years.
If you are not CPR-trained, you can receive training through one of the following organisations, though
please note that this list is not exhaustive:
- British Red Cross: www.redcrossfirstaidtraining.co.uk
- Bart City Life Saver: www.bartscitylifesaver.org
- St Andrew's First Aid: www.firstaid.org.uk
- St John's Ambulance: www.sja.org.uk
After a cardiac arrest, every minute without CPR (cardiopulmonary resuscitation) and defibrillation reduces someone's chance of survival by 10 per cent. 
CPR is a first aid technique that uses chest compressions and rescue breaths to keep blood and oxygen circulating in the body. It serves as the foundation of successful resuscitation and survival, preserving the body for defibrillation and advanced life support.
Immediate CPR followed by defibrillation within 3-5 minutes of ventricular-fibrillation cardiac arrest dramatically improves survival. Even in the case of a "non-shockable" arrests, effective CPR is no less important. Used alone, CPR will result in few complete recoveries, though the outcome without CPR is almost uniformly fatal.
There are up to 175,000 heart attacks in the UK each year—one every three minutes. 60,000 cardiac arrests happen out of hospital, less than one in ten survive. 
This initiative is inspired by the SMSlivraddare service in Sweden. In their trials, 40% of their participants arrived at the scene before an ambulance.
A while after the alarm, the heartsaver might be contacted with a follow-up message as to describe what happened. This is partly due to it being a research project and also due to a possibility for the lifesavers to tell us in the project if they wish to have more contact about what happened.