Saving lives in an emergency

There are more than 30,000 out-of-hospital cardiac arrests in the UK each year. A cardiac arrest means that the heart has suddenly stopped pumping blood around the body. It’s usually caused by a life-threatening abnormal heart rhythm, often due to a heart attack or, less commonly, an inherited heart condition. Even now, in the UK, fewer than 1 in 10 people survive an out-of-hospital cardiac arrest.

Since our inception in 1961, we’ve been working to change this. The first step was to make the emergency equipment that existed in hospitals available to those who collapsed at home, at work, or on the street.

The first mobile coronary care unit

In 1965, BHF funding helped to launch the UK’s first mobile coronary care unit in Belfast, bringing emergency heart attack care to patients before they arrived at hospital. Led by Dr Frank Pantridge, the team conceived the idea for the mobile unit, essentially an ambulance with specialist equipment and staff to provide heart care before someone arrived at hospital. This included the world’s first portable defibrillator, a device to shock the heart back into a stable heart rhythm after cardiac arrest. Although portable compared with previous models, it was the size of a fridge and weighed over 70kg.

Within a year, Dr Pantridge reported that the Belfast team could now reach 85 per cent of patients in under 15 minutes. The Belfast experiment was widely acclaimed, and the idea was quickly taken up in the USA, although it took longer to be widely adopted in the UK.

In the 1970s, Professor Douglas Chamberlain in Brighton, with support from BHF, built on Dr Pantridge’s work. He replicated what Dr Pantridge was doing in Belfast and started to train ambulance crews to use defibrillators. A decade later, a BHF-funded pilot proved their life-saving potential. In 1990, the UK government made defibrillators standard in all ambulances.

Putting defibrillators on the map

In the 1980s, Professor Chamberlain and BHF started campaigning to make defibrillators available in public places around the UK. In the last decade alone, BHF has helped fund over 4,000 public access defibrillators across the UK, prioritising communities which needed them the most.

However, access alone isn’t enough—many defibrillators go unused simply because ambulance services don’t know where they are. In 2020 it was estimated that up to 70% of defibrillators in the UK were unknown to ambulance services. That’s a critical gap, especially when every minute without cardiopulmonary resuscitation (CPR) and defibrillation reduces the chance of surviving an out-of-hospital cardiac arrest by up to 10%.

To close this gap, with an estimated target of 100,000 defibrillators, BHF joined forces with St John Ambulance, Resuscitation Council UK and the Association of Ambulance Executives. Together, we launched The Circuit, the UK’s first nationwide defibrillator network. The goal was to create a live, centralised database of defibrillators that synchronises every 60 seconds with the dispatch systems of all UK ambulance services. In 2022, all UK ambulance services were successfully connected to the database. This means ambulance service call handlers could now dynamically locate the nearest registered defibrillator and guide bystanders to it. Over time this world-leading initiative should help to significantly increase survival rates from out-of-hospital cardiac arrests through bystander defibrillation.

The Circuit partnership continues to grow with NHS England and Save a Life Cymru joining the collaboration. As of 2025, over 110,000 defibrillators are registered on The Circuit. However, it is estimated that tens of thousands of defibrillators are still unregistered. BHF continues to urge individuals, businesses, and communities register their defibrillator and ensure The Circuit is regularly updated. Knowing where the nearest emergency ready defibrillator is could mean the difference between life and death.

Creating a Nation of Lifesavers

Despite the progress made in getting defibrillators into ambulances and public spaces, survival still depends on someone nearby acting quickly. Recognising this, in the early 1980s, Professor Douglas Chamberlain—supported by BHF—began training members of the public in CPR.

Since then, BHF has been committed to creating a Nation of Lifesavers, supporting CPR training in schools and communities across the UK. Millions have learned life-saving skills using BHF training kits in schools, workplaces, and community groups. 

Thanks to years of campaigning by BHF and other organisations, CPR training has become a key part of education across the UK. In 2019, all 32 local authorities in Scotland committed to ensuring every pupil learns CPR before leaving secondary school. England followed in 2020, adding first aid and CPR to the secondary school curriculum. Northern Ireland and Wales have since introduced similar commitments, with CPR training becoming statutory in secondary schools from 2022 and 2023 respectively.

Building on this legacy, in 2022, BHF launched RevivR—a free, interactive online tool that teaches CPR in as little as 15 minutes using only a phone and a cushion. It helps people recognise a cardiac arrest, practise CPR with real-time feedback, and learn how to use a defibrillator—wherever you are.

Early CPR and defibrillation can more than double the chances of surviving an out-of-hospital cardiac arrest, yet many people still hesitate to act. RevivR is helping to close that gap by making life-saving skills more accessible than ever.

Updated July 2025