Out-of-hospital cardiac arrest is one of the few medical emergencies where an untrained member of the public, acting in the first minutes, changes the outcome more than anything a hospital can do later. It is also the emergency where most health systems still lose more than nine patients out of ten.

This page brings together the most recent verifiable figures on cardiac arrest incidence, survival, bystander intervention and the measurable effect of organised citizen responder networks. It is the evidence base we use with emergency medical services, cities and public authorities when we design a deployment.

How many people are affected

Europe

The European Registry of Cardiac Arrest study EuReCa TWO remains the largest coordinated measurement of the problem across the continent. Over three months, 28 countries covering a population of 178,879,118 confirmed 37,054 out-of-hospital cardiac arrests, with resuscitation attempted in 25,171 of them.

That corresponds to an incidence of roughly 83 cases per 100,000 inhabitants per year. Applied to the European Union population, it points to somewhere between 350,000 and 400,000 out-of-hospital cardiac arrests every year, or one roughly every 90 seconds.

United States

The American Heart Association’s 2026 Heart Disease and Stroke Statistics Update reports that sudden cardiac arrest contributed to 380,349 deaths in the United States in 2023. The Cardiac Arrest Registry to Enhance Survival estimates 263,711 emergency-treated non-traumatic out-of-hospital cardiac arrests for 2024.

Who it happens to

• Men are affected roughly twice as often as women.
• The median age of victims is around 65, but cardiac arrest occurs at every age, including in children and in athletes with no known heart condition.
• The majority of cases happen at home, not in public places. This single fact is why public defibrillator programmes alone never close the gap.

Survival: low, and unequal

Survival to hospital discharge after out-of-hospital cardiac arrest was 8% across Europe in EuReCa TWO, and 10.5% in the United States in 2024 according to the American Heart Association. The United States figure has barely moved in thirty years.

The striking finding is not the average. It is the spread between countries that share the same medicine, the same drugs and the same defibrillators:

• Bystander CPR rates range from 13% to 82% between European countries, for an average of 58%.
• In the United States, only 42% of victims received bystander CPR and only 13% had a public defibrillator used on them before the ambulance arrived.
• Survival to discharge varies by more than a factor of ten between the best and worst performing European systems.

In other words, the variable that separates a 5% survival rate from a 25% survival rate is not clinical. It is organisational: how fast a trained pair of hands and a defibrillator reach the patient.

Doubling survival: the evidence

A study conducted with the Paris Fire Brigade, one of the largest urban emergency services in Europe, measured what happens when a geo-located citizen responder is dispatched to a cardiac arrest alongside the professional response:

• Survival without a citizen responder on scene: 16%.
• Survival with a citizen responder on scene: 35%.

Registry data points the same way. In the 2024 United States CARES data, survival to hospital discharge was 13.0% when a bystander performed CPR, against 7.6% when nobody did.

Neither result requires new technology or new drugs. It requires a system that knows who is nearby, where the nearest defibrillator is, and how to reach both in under three minutes.

The Staying Alive network in figures

Staying Alive operates the citizen responder network behind these results. As of 2026:

• 500,000+ registered citizen responders.
• 2.5 million+ app downloads.
• 100,000 alerts dispatched since launch, a milestone reached in June 2026, of which more than 22,000 in a single year.
• 400,000+ defibrillators mapped and maintained in the largest AED database in France.
• Live in 90 French départements and integrated with emergency dispatch centres, plus deployments in Belgium and Luxembourg.

Target for 2029: one million citizen responders and 20,000 lives saved every year in France alone.

Most cardiac arrests are preceded by ischaemic heart disease. The main cardiovascular risk factors are:

• High blood pressure.
• Type 2 diabetes.
• High cholesterol.
• Physical inactivity and excess weight.
• Smoking.
• Family history of cardiovascular disease.
• Chronic stress.

Cardiac arrest can strike with no warning at all. But chest pain, prolonged palpitations or unusual breathlessness should never be waited out. They are reasons to seek medical advice the same day.

Cardiac arrest is not a heart attack

The two are routinely confused, including by trained professionals under pressure, and the response is completely different.

• A heart attack is a blocked coronary artery. The patient is conscious, usually in pain, often sweating, and is breathing. Call the emergency number immediately and keep them still.
• A cardiac arrest is the abrupt failure of the heart’s electrical activity. The patient collapses, is unresponsive and is not breathing normally. Call, start chest compressions, and get a defibrillator on the chest as fast as possible.

An untreated heart attack can degenerate into cardiac arrest. In both cases the first minutes decide the outcome.

The chain of survival describes the sequence that turns the statistics around:

1. Early recognition of cardiac arrest.
2. Immediate call to the emergency number (112 across the European Union, 911 in North America, 999 in the United Kingdom).
3. Cardiopulmonary resuscitation started by whoever is present.
4. Early defibrillation with an AED.
5. Advanced life support and post-resuscitation care by professionals.

The first four links depend entirely on people who are not emergency professionals. That is the part of the chain a citizen responder network is built to strengthen, and the part where every health system still has the most ground to gain.

Sources and method

• Gräsner J.T. et al., Survival after out-of-hospital cardiac arrest in Europe: results of the EuReCa TWO study, Resuscitation, 28 countries, population 178,879,118.
• American Heart Association, 2026 Heart Disease and Stroke Statistics Update, top takeaways.
• Cardiac Arrest Registry to Enhance Survival (CARES), 2024 data, via the Sudden Cardiac Arrest Foundation.
• Derkenne C. et al., Mobile smartphone technology is associated with out-of-hospital cardiac arrest survival improvement: the first year Staying Alive experience, Academic Emergency Medicine.

European and national figures are not directly comparable: registries differ in inclusion criteria, in the definition of an attempted resuscitation and in follow-up. Where a range exists, we give it rather than a single average.

Read next

• Cardiac arrest: the actions that save lives
• Automated external defibrillators: the complete guide
• How to use a defibrillator
• How we deploy a citizen responder network