CPR being performed on a person

Heart attack vs cardiac arrest

Understand the differences between these life-threatening, but unique, conditions

Most of us have heard of heart attack and cardiac arrest - but did you know these terms do not refer to the same condition?

While heart attack and cardiac arrest are both medical emergencies that affect how the heart functions, each one has different causes, levels of severity, and treatments.

Understanding the difference between these conditions is the key to saving lives.

What is the difference between a heart attack and a cardiac arrest?

A heart attack is a blood supply problem to the heart, which occurs when an artery that supplies oxygen to the heart is suddenly blocked, starving the heart of oxygen.

When this happens, the heart muscle cells begin to die. The longer the heart is without oxygen, the more permanent the damage.

A cardiac arrest is an electrical problem in the heart that causes the heart to suddenly stop pumping blood.

Cardiac arrest causes loss of heart function, breathing and consciousness. This can lead to death within 10 minutes if untreated.

What's the link between cardiac arrest and heart attack?

While these two conditions are different, there are links between them such as:

What should you do if someone goes into cardiac arrest?

If a cardiac arrest is suspected, you should:

What should you do if someone is having a heart attack?

If a heart attack is suspected, you should:

    How to tell the difference between cardiac arrest and heart attack 

    Heart attack

    Blood supply issue

    Cardiac arrest

    Electrical issue
    When an artery that supplies oxygen to the heart is blocked, starving the heart of oxygen When the heart stops beating due to an electrical problem in the heart
    • Pressure, tightness or pain in the chest and arms which may spread to the neck, jaw or back
    • Nausea and/or vomiting
    • Indigestion or heartburn
    • Cold sweat
    • Fatigue
    • Light-headedness
    • Sudden dizziness
    • Fainting
    • Sudden collapse
    • No pulse
    • No breathing
    • Loss of consciousness
    Time frame
    Symptoms can progress over minutes to hours Symptoms are immediate and will cause sudden death within 10 minutes if untreated
    What to do
    • Call 000 (in Australia)
    • Chew aspirin (unless allergic)
    • Take nitroglycerin (if prescribed by a doctor)
    • If the person becomes unconscious:
    • Call 000 (in Australia)
    • Begin CPR
    • Use an AED

    Frequently asked questions about heart attack and cardiac arrest

    Which is worse: heart attack or cardiac arrest? 

    The likelihood of dying from a cardiac arrest is much higher than for heart attack.

    90% of people will not survive an out of hospital cardiac arrest. Without treatment, a cardiac arrest will cause sudden death within 10 minutes.

    For Australians who have a heart attack, the survival rate is 76.2 per cent after three years, 68.6 per cent after five years, and 62.3 per cent at seven years.

    For those aged under 65, survival rates after seven years exceed 85 per cent.

    What comes first: heart attack or cardiac arrest?

    Both heart attack and cardiac arrest can occur independently.

    Having a heart attack does however put you at higher risk of experiencing cardiac arrest.

    Do all heart attacks lead to cardiac arrest?

    Heart attacks don’t always lead to cardiac arrest, but heart attacks are a common cause of cardiac arrest.

    Can a healthy person have a heart attack or go into cardiac arrest?

    Heart attack

    High cholesterol – in particular high levels of ‘bad’ cholesterol such as LDL and Lp(a) - can be genetic and can occur in those with otherwise healthy lifestyles. This is known as familial hypercholesterolemia.

    High cholesterol is a risk factor for heart attack.

    It is important to speak to your doctor if your family has a history of high cholesterol, or early heart attack, stroke, or unexplained death.

    Cardiac arrest

    People with normal, healthy hearts can suffer a cardiac arrest due to triggers such as:

    • an electrical shock
    • use of illegal drugs
    • trauma to the chest at the wrong time of the heart’s cycle
    • genetic causes such as rare genes that can cause issues with the electrical stability of the heart rhythm

    People with certain undiagnosed heart conditions are also at risk of cardiac arrest.

    Acknowledgement of Country

    The Victor Chang Cardiac Research Institute acknowledges Traditional Owners of Country throughout Australia and recognises the continuing connection to lands, waters and communities. We pay our respect to Aboriginal and Torres Strait Islander cultures; and to Elders past and present.

    Victor Chang Cardiac Research Institute - The Home of Heart Research for 30 Years