Heart Attack v’s Cardiac Arrest

Heart disease is our biggest killer, and in Australia, about 54,000 people have a heart attack each year, of these about 10,000 will die – that’s close to one person every 53 minutes. Estimates suggest between 20,000 to 33,000 people die of a cardiac arrest each year.

Both heart attacks and cardiac arrests are medical emergencies involving your heart that require immediate treatment, but they are not the same thing. The most common source of confusion is the difference between a heart attack and cardiac arrest.

A heart attack occurs when a coronary artery becomes blocked, preventing blood flow to part of the heart muscle. During a heart attack, a person remains conscious and keeps breathing.

While a heart attack is a plumbing problem, a cardiac arrest is an electrical problem. Cardiac arrest happens when the heart’s electrical system malfunctions, causing it to beat rapidly and chaotically — or to stop beating altogether. Without blood circulating to the brain, lungs, and other organs, the person gasps or stops breathing and becomes unresponsive within seconds.

Sometimes a heart attack can cause a cardiac arrest. This is because a person who is having a heart attack may develop a dangerous heart rhythm, which causes a cardiac arrest. A heart attack and a cardiac arrest are both emergency situations.

What do they look like?

Sudden cardiac arrests usually occur without warning; if someone has a cardiac arrest, they will suddenly become unconscious and show no signs of breathing or not breathing normally. Heart attack symptoms vary from person to person but can include:

  • pain, discomfort or heaviness in the centre of your chest
  • pain or discomfort in your jaw, back, neck, shoulders or arms
  • weakness
  • cold sweats
  • nausea
  • dizziness
  • feeling short of breath

How is cardiac arrest treated?

A cardiac arrest is a medical emergency which is often fatal if not treated quickly with a combination of cardiopulmonary resuscitation (CPR) and defibrillation (AED).

CPR is a combination of rescue breathing and chest compressions. It provides oxygen to the lungs and keeps oxygenated blood circulating until an effective heartbeat and breathing can be restored. By knowing and performing CPR, you may save a life.

Defibrillation is the use of an electric shock through the chest wall to correct the abnormal heart rhythm. It is carried out using a machine called a defibrillator and it’s an essential part in trying to save the life of someone who’s in cardiac arrest. You don’t need to be trained to use a defibrillator – anyone can use it.

3 steps to save a life

1. Call 000 for an ambulance and ask someone to bring the AED if one available

2. Start CPR (hands only compressions) 100 – 120 compressions per minute

3. Turn on the AED and follow voice prompts.

If you would like to learn how to perform CPR and use a defibrillator, head over to our first aid course page for more information.

A cardiac arrest can happen to anyone, at any time. Make sure you are prepared.