Cardiac arrest occurs when the heart stops beating suddenly; it is the most extreme medical emergency and requires an immediate response. Cardiac arrest can happen to both adults and children, though it is more common in later life.
In the United Kingdom each year 60,000 people suffer a sudden cardiac arrest outside hospital. Approximately half of these (30,000 people) receive a resuscitation attempt from the ambulance service, however the recovery rate remains disappointingly low with only 9% surviving to leave hospital.
Read More on the NHS Digital website.