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Coronary artery disease

Coronary artery disease, also called ischaemic heart disease, happens when the major blood vessels in the heart get narrow and stiff. It can cause heart attacks and angina. Read about its symptoms, causes and its treatment.

Coronary artery disease (CAD) is the most common kind of heart disease. More than 170,000 people in New Zealand have it and it’s the main cause of heart attacks and angina.

Sometimes you’ll hear coronary artery disease called other names, like ischaemic heart disease (IHD), or coronary heart disease (CHD). Sometimes it’s just called heart disease. These are just different terms for the same condition.

What is coronary artery disease?

Coronary arteries are the blood vessels that take oxygenated blood to your heart muscle to keep it pumping.

heart with arrows to the left coronary artery, aorta and right coronary artery

Coronary artery disease occurs when fatty material (plaque) builds up in these arteries.

These streaks of fatty material cause the arteries to narrow and stiffen. The clinical term for this is atherosclerosis.

As the arteries get narrower, it becomes harder for blood to reach the heart muscle. This sometimes causes pain or discomfort called angina.

If a piece of the plaque cracks, it may cause a blood clot to form. This stops the blood getting to part of the heart muscle. This is a heart attack (or myocardial infarction).

Comparison of coronary artery disease, angina and a heart attack in the arteries. Coronary artery disease - plaque builds up in an artery. Angina, it is harder for blood to get through the artery. Heart attack - plaque cracks and a blood clot blocks the artery.

Learn about how the heart works

Is coronary artery disease the same as cardiovascular disease?

Coronary artery disease is a type of cardiovascular disease (CVD).

CVD is any disease or condition involving the heart and/or blood vessels.

It includes lots of different conditions such as:

  • coronary artery disease
  • stroke
  • heart valve problems
  • heart failure
  • cardiomyopathy
  • congenital heart conditions.

Symptoms of coronary artery disease

You may not know you have CAD because it doesn’t always cause symptoms. When arteries narrow it may cause pain and discomfort. Often this happens when your heart is working harder, like when you are walking up hill or stairs. Symptoms can include:

  • unusual breathlessness, for example when at rest or undertaking very light physical activity
  • discomfort, heaviness or tightness of the chest which may spread to the back, shoulders, neck or jaw. Other people describe it as a dull ache
  • discomfort in the arm, neck or jaw with no chest discomfort.

The discomfort can range from mild or dull to severe. Sometimes people only discover they have coronary artery disease when it causes a heart attack.

What are the heart attack warning signs?

Causes and risk factors

There are a number of things that make you more likely to develop coronary artery disease. These things are called risk factors.

Some risk factors you can’t control (uncontrollable risk factors), but others you can control through lifestyle changes and medication (controllable risk factors).

Controllable risk factors include:

  • smoking – smoking damages the lining of your arteries, increasing the build of fatty materials which narrow the artery. It also makes your blood more likely to clot.
  • cholesterol – having high cholesterol increases the speed fatty materials build up in your arteries.
  • blood pressure – over time high blood pressure can damage your arteries.
  • diabetes – diabetes increases the risk of coronary artery disease and makes you more likely to have a heart attack or stroke. Although you may not be able to prevent your diabetes, managing your condition may help you lower your risk of heart attack and stroke.
  • exercise – just 30 minutes of moderate activity a day can reduce your risk of CAD.
  • weight – being a healthy weight helps to reduce your risk of coronary artery disease.
  • diet – a heart-healthy diet provides your body with the best possible nutrients, as well as helping you to maintain a healthy weight.
  • stress/anxiety – long term stress can increase your risk of heart attack and stroke. Find out how to manage stress.
  • alcohol intake – heavy drinking or binge drinking can increase your risk of heart disease.

Uncontrollable risk factors include:

  • age – your risk of CAD increases with age
  • gender – men are more likely to develop CAD at an earlier age than women. However women’s risk increases after they stop getting their periods
  • ethnicity – people from certain ethnicities, such as Māori, Pasifika people and those from South Asian countries, are at higher risk of heart disease
  • mental health history – people with severe mental illness are at higher risk of heart disease than the general population
  • family history – you are at greater risk of heart disease if a close relative was diagnosed with heart disease before the age of 50.

What’s my personal risk of developing coronary artery disease?

It’s important you know your own level of risk and at what age you should get a heart check.

How do I find out my risk?


Coronary artery disease can lead to a number of other heart conditions, including:

If you’ve been diagnosed with CAD, ask your doctor about how you can reduce your risk of developing these complications.

How is CAD diagnosed?

Doctors will diagnose your condition using a number of tests. These will depend on:

  • how high your risk is
  • your symptoms
  • any complications you’ve had, like a heart attack.

Common tests include:


You can’t cure coronary artery disease, but there are things you can do to stop it getting worse. Your treatment will depend on your risk factors, and any complications you’ve had, like a heart attack. It will usually involve one or more of the following:

  • lifestyle changes 
  • medication 
  • surgical procedures. 

Lifestyle changes

Suggested lifestyle changes may include:

  • quitting smoking
  • moving more 
  • making heart-healthy eating and drinking choices
  • losing weight
  • reducing your stress levels. 

choices you can make to lower your risk of heart attack and stroke. Quit smoking, move more, eat healthily, lose weight

You can find tips on ways to achieve these goals in the managing your risk section of our website.


Your doctor may suggest one or more medications depending on:

  • your symptoms
  • your risk of future heart events
  • any complications you’ve had, such as heart attack or heart failure.

These medications could include:


If you have angina or if you’ve already had a heart attack, your doctor may suggest one of the following procedures.

Angioplasty and stents

Angioplasty is a treatment that uses a special balloon to widen a narrow or blocked artery and restore blood flow to the heart. During the procedure, the doctor will usually put a small mesh tube called a stent into the artery to keep it open. Read more on our angioplasty page.

Coronary Artery Bypass Graft (CABG) Surgery

Bypass surgery improves blood flow to the heart to treat angina. During the surgery, the cardiologist takes a blood vessel from another part of your body (usually your leg or arm) and uses it to make a new way for blood to flow around a blocked artery. Read more on our CABG page.

Living well with coronary artery disease

Although you can’t cure coronary artery disease, you can live a long and fulfilling life with it. There are also lots of things you can do to manage your condition and reduce your risk of future heart events.

If you’ve just been diagnosed, it’s normal to feel scared or overwhelmed. It’s important to get as much support as possible – physically and emotionally.

Attending cardiac rehabilitation is a great way to find out more about your condition. You’ll learn ways you can help yourself and meet people who’ve been through a similar experience.

You could also get a green prescription. This is a free government-led programme which helps people with exercise and nutrition advice. The programme includes free consultations with a trained activity coach and the opportunity to participate in local activity programmes.

Connecting with others

Sometimes it’s helpful to hear from others who are living with coronary artery disease. You can read personal stories from people who’ve shared their experience as part of our Journeys programme. You’ll find a range of stories about people who’ve had heart attacks, angina, or are living with risk factors such as high cholesterol and high blood pressure.

You can also join a cardiac support group in your local area. Find them in our heart help directory. The Heart Foundation also runs regular events on a range of heart-related topics.

How can I reduce my risk of future heart events?

There’s a lot you can do to reduce your risk of future heart events. Making the lifestyle changes above and continuing to take your medication as prescribed are two important things you can do to reduce your risk of a heart attack, or another kind of heart event.

Find out when you’re due a heart and diabetes check with your doctor or nurse.

You’ll also find lots of information on our managing your risk section of the website and living well after a heart attack.

Learn more about heart attacks

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