Heart attack

About the heart

Your heart is a vital organ. It is one of your most important muscles as it pumps blood carrying oxygen and nutrients to all parts of your body.

For your heart to function properly, it needs a good blood supply.

A heart attack, also known as myocardial infarction (MI), occurs when one or more of the arteries that supply blood to the heart muscle is blocked. This stops the blood flow and reduces the amount of oxygen that gets to your heart muscle.

Heart attack warning signs

Recognising the warning signs of a heart attack and calling triple zero (000) could save your life, or the life of a loved one.

It’s important that everyone knows the warning signs of a heart attack because early treatment is vital. The longer a blockage is left untreated, the more damage occurs.

When having a heart attack, you may experience pain, pressure, heaviness or tightness in one or more parts of your upper body, including your:

• chest
• shoulder
• neck
• arm
• jaw
• back.

This may occur in combination with other warning signs such as:

• nausea, indigestion or vomiting
• dizziness, light-headedness or feeling faint
• sweating or breaking out in a cold sweat
• shortness of breath or difficulty breathing.

Warning signs of a heart attack vary from person to person and they may not always be sudden or severe.

You may have just one of these warning signs or you may have a combination of them. They usually last for at least 10 minutes and may come on suddenly or get worse as time passes.

Although chest pain or discomfort is the most common warning sign of a heart attack, some people will not experience chest pain at all, while others will experience only mild chest pain or discomfort.

Heart attack warning signs can be different for women. While chest pain is the most common heart attack warning sign in both women and men, women are more likely than men to experience the non-chest pain warning signs listed above, along with feeling fatigued or tired.

It is also possible to experience a ‘silent heart attack’, where you might not have any symptoms at all. In this case, your heart attack might not be picked up until later down the track.

If you, or someone you know, are experiencing the warning signs of a heart attack – tell someone. If symptoms are severe, or getting worse, or last for more than 10 minutes, call triple zero (000) immediately and ask for an ambulance.

Heart attack action plan

You can download a free heart attack action plan (available in 17 languages) to learn more about the warning signs of a heart attack and steps to take in the event of a medical emergency.

Causes of a heart attack

The most common underlying cause of a heart attack is coronary heart disease. This occurs when fatty deposits (called plaque or atheroma) slowly build up on the inner wall of the coronary arteries and cause the arteries to become narrow.

During a heart attack, plaque from the artery wall breaks away (ruptures) and can form a clot. This can block the flow of blood through the artery and cause damage to the heart muscle.

Other less common causes of a heart attack include:

• tearing of the coronary artery wall (spontaneous coronary artery dissection)
• sudden contraction and narrowing of the coronary artery (coronary artery spasm).

To find out your risk of having a heart attack, see your doctor for a Heart Health Check if you are over the age of 45 (or 30 for Aboriginal and Torres Strait Islander people).

Diagnosing a heart attack

A heart attack is a medical emergency. Diagnosis and treatment can start in the ambulance.

Once you get to the hospital, further tests will be performed to confirm a heart attack.

These tests will also measure the amount of damage to your heart and what treatment you need. Tests to diagnose a heart attack include:

• electrocardiogram (ECG) – to measure the electrical activity of your heart
• blood tests – including a troponin test to measure levels of enzymes (proteins) released into the blood when the heart muscle is damaged
• coronary angiogram – a long, thin tube (catheter) is inserted into an artery in your wrist (or sometimes the groin). The catheter is threaded through the artery until it reaches your heart. A special dye is then injected into the catheter and an X-ray is taken. The X-ray shows where the coronary arteries are blocked.

Treatment for a heart attack

A heart attack requires emergency treatment to restore blood flow to your heart. The faster this happens, the less damage to the heart muscle.

Heart attack treatments may involve medicines or surgery.

Medicines for heart attack

To treat your heart attack in the ambulance or hospital, your doctor may prescribe a medicine called thrombolysis (or thrombolytic therapy).

Thrombolysis is a treatment to dissolve blood clots that are narrowing or blocking a coronary artery. The ‘clot-busting’ medicine is given to you through a drip. Dissolving the clot improves blood flow to your heart muscle and around your body.

To reduce the risk of future heart attacks, your doctor will also start you on medicines while you’re recovering in hospital. You will need to continue taking these over the long-term.

It’s very important to keep taking your medicines unless your doctor or cardiologist tells you to stop. Have regular check-ups with your doctor so they can review your medicines and adjust them as needed.

Commonly prescribed medicines after a heart attack include:

• antithrombotic medicines like anticoagulants and antiplatelets – to reduce the risk of blood clots forming
• beta blockers – to lower blood pressure and regulate your heart rate and rhythm
• blood pressure medicines like angiotensin converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) – to make it easier for your heart to pump blood and lower blood pressure by widening your blood vessels
• cholesterol-modifying medicines – to reduce your cholesterol levels.

Surgical procedures

Following a heart attack, some people may need surgery to open up a blocked artery. This can include:

• coronary angioplasty and stent insertion – a procedure to open up a blocked coronary artery using a balloon. Once the artery is open, a special expandable tube (stent) is left in place to keep it open, and the balloon is withdrawn. This improves blood flow to your heart
• coronary artery bypass graft (CABG) surgery – an operation where a healthy blood vessel (can be a vein or artery from your arm, leg or chest) is attached to either side of the blocked artery in your heart and is used to allow blood flow to your heart again.

Preventing another heart attack

A heart attack can be a life-changing event. It’s normal to feel scared, confused and overwhelmed after a heart attack.

The good news is there are many resources available to support you in recovering after a heart attack.

Having one heart attack increases your risk of having another. Participating in cardiac rehabilitation, taking your medicines as prescribed and maintaining a healthy lifestyle can help reduce the likelihood of a future heart attack. Being part of a support group can be useful for some people too.

Participate in cardiac rehabilitation

Cardiac rehabilitation (or cardiac rehab) is a program of support, exercise and education that is led by health professionals to improve your recovery and quality of life.

Attending cardiac rehab can help you recover and return to live a full and active life. You will also be supported to make long-term lifestyle changes to improve your heart health and wellbeing.

Speak to your doctor or visit the Heart Foundation’s Cardiac Services Directory to find out more about a local cardiac rehab program tailored to your needs.

Take your medicines as prescribed

Medicines can help protect your heart and lower the risk of future heart problems.

It’s important to know which heart medicines you are taking, what they are for and the possible side effects to look out for. For more information about your heart medicines, speak to your doctor or pharmacist.

Always talk to your doctor before taking any other medicines that you buy over the counter. Over-the-counter medicines are medicines you can buy from a pharmacy, supermarket or health food shop without a prescription. Many over-the-counter medicines (including pain medicines, cold and flu medicines, supplements and vitamins) can interact with your heart medicines.

Make lifestyle changes

Following a heart-healthy lifestyle can help prevent another heart attack:

• Quit smoking and limit exposure to second-hand tobacco smoke.
• Be physically active most days of the week.
• Follow a heart-healthy eating pattern.
• Drink less alcohol.
• Look after your mental health.
• Maintain a healthy body weight.
• Manage your blood pressure and cholesterol levels.
• Manage your blood sugar levels, for people with diabetes.

Join a support group

There are many benefits to joining a support group. You can meet others who have had a similar experience, get practical advice and gain emotional support.

Find out more about support and walking groups available through the Heart Foundation.

Where to get help

• In an emergency, always call triple zero (000)
• Your GP (doctor)
• Cardiologist
• Emergency department of your nearest hospital
• Heart Foundation
• NURSE-ON-CALL Tel. 1300 60 60 24 – for expert health information and advice 24 hours a day, 7 days a week