The ABC of Cardioprotection: Essential AED & Cardiac Emergency TermsH1

13 April 2026

Defibrillator? Arrhythmia? Lay responder? Talking about cardiac emergencies can feel complex without a medical background. If the basic concepts aren’t clear, it becomes difficult to understand what’s happening—and how to respond effectively.

That’s why we’ve created this basic glossary. It explains key cardioprotection terms in a simple way, helping you become familiar with them and build a clearer understanding of this life-saving topic.

Understanding Key Cardiac Emergency Terms: AED, Arrhythmia, and First Responders

Cardiac arrhythmias

Also known as irregular heart rhythms, arrhythmias occur when the heart beats abnormally—either too fast (tachycardia) or too slow (bradycardia).

There are several types of arrhythmias, but those that lead to cardiac arrest typically disrupt the heart’s ability to pump blood effectively.

Chain of survival

This refers to a sequence of critical actions performed in a specific order to improve survival during cardiac arrest.

According to the American Heart Association’s 2020 Guidelines for CPR and ECC, the chain of survival for out-of-hospital adult cardiac arrest includes:

Calling emergency services as soon as cardiac arrest is suspected
Starting high-quality CPR
Early defibrillation
Advanced life support by healthcare professionals
Post–cardiac arrest care
Recovery and follow-up

Automated External Defibrillator (AED)

A device that delivers a controlled electric shock to restore normal heart rhythm.

AEDs automatically analyze the heart rhythm and deliver a shock if a shockable rhythm is detected. They are designed for use outside hospital settings and provide step-by-step voice instructions.

Cardioprotection

Cardioprotection involves taking measures to prevent death from cardiac arrest due to lack of timely care. These measures include installing Automated External Defibrillators (AEDs) in public places (such as shopping centres and stadiums) and private spaces (offices or residential buildings), as well as ensuring trained personnel are available to respond.

Chest compressions

Chest compressions help maintain blood flow to vital organs such as the brain and lungs. They should be performed in the centre of the chest with both hands, at a rate of 100 to 120 compressions per minute, continuously and without interruption.

Tools such as metronomes—often included in AEDs or available as apps—help maintain the correct rhythm until emergency services arrive.

CPR (Cardiopulmonary Resuscitation)

A set of life-saving actions performed to revive someone who has lost consciousness and is suspected of cardiac arrest. It includes continuous chest compressions and timely defibrillation.

Defibrillation

The delivery of an electric shock to restore the heart’s normal electrical activity.

External defibrillation

A controlled electric shock delivered using a defibrillator to help restart the heart.

Fibrillation

A condition where parts of the heart quiver instead of contracting properly, preventing effective blood circulation. Without prompt treatment, it can lead to cardiac arrest.

First responder

Any individual who provides initial assistance to a person experiencing cardiac arrest.

Heart-safe environment (Cardioprotected space)

A public or private space prepared to respond to cardiac emergencies. It includes strategically placed AEDs and trained personnel capable of performing CPR and using a defibrillator.

Lay responder

Any person with basic first aid knowledge who can assist in a cardiac emergency.

Metronome

An auditory guide that helps maintain the correct rhythm for chest compressions.

Semi-Automatic External Defibrillator (SAED)

Similar to an AED, but requires the user to press a button to deliver the shock when prompted.

Build a Heart-Safe Workplace with AEDs and CPR

Understanding what an AED is and how to use it, along with the chain of survival steps during cardiac arrest, is only the first step.

What truly saves lives is being prepared—with trained responders, accessible AEDs, and a clear plan. If you’re ready to create a heart-safe workplace with CPR and AEDs, we can help you implement the right solution.