Coronary artery disease

Also known as coronary heart disease and ischaemic heart disease (IHD)

Coronary artery disease (CAD) is the most common type of heart disease and happens when the arteries that supply blood to your heart muscle (the coronary arteries) become hardened and narrowed. A gradual blockage can result in angina. A sudden or severe blockage can cause a heart attack or cardiac arrest.

Key points

  1. Coronary artery disease and stroke are the number one causes of death and disability in New Zealand.
  2. One in 20 adults have been diagnosed with heart disease. That's more than 165,000 New Zealand adults.
  3. Every 90 minutes a New Zealander dies from heart disease. Many of these deaths are premature (the person dies too early) and could be prevented. 
  4. You can reduce your risk by being smokefree and physically active, eating heart healthy foods, keeping to a healthy weight and having your blood pressure and cholesterol checked. 
  5. If you are 35 or older, check the age you should start having a heart check.

What are the causes of coronary artery disease (CAD)?

The narrowing of the coronary arteries can be due to the buildup of cholesterol and other material, called plaque, on their inner walls. This build-up is called atherosclerosis. As it grows, less blood can flow through the arteries. As a result, the heart muscle can't get the blood or oxygen it needs. This can lead to angina (chest pain) or a heart attack.

Most heart attacks happen when a blood clot suddenly cuts off the hearts' blood supply, causing permanent heart damage. Over time, CAD can also weaken the heart muscle and contribute to heart failure and arrhythmias.

  • Heart failure means the heart can't pump blood well to the rest of the body.
  • Arrhythmias are changes in the normal beating rhythm of the heart.

What increases my risk of coronary artery disease?

There are a number of factors that are known to increase your risk of CAD. Some risk factors you can’t do anything about. These include age, ethnicity, gender, personal or family history of heart attack or stroke. 

Other risk factors you can change and making these changes can have a huge impact on your heart health and general wellbeing. Your risk of developing CAD is significantly increased if you: 

Are you at risk of heart disease? Find out with our heart risk assessment

When should I start having heart checks?

The age when you are advised to start having heart checks changes, depending on your age, ethnicity and other risk factors.


1. South-Asian peoples: Indian, including Fijian Indian, Sri Lankan, Afghani, Bangladeshi, Nepalese, Pakistani, Tibetan
2. Family history: parent, brother or sister
3. Overweight: BMI ≥ 30 or weight around your tummy (waist circumference ≥ 102 cm in men or ≥ 88 cm in women)
Men Women
If you have no known risk factors
  • 45 years
  • 55 years
If you are Māori, Pasifika or South Asian1
  • 30 years
  • 40 years

If you have the following risk factors:

  • you smoke
  • you have a family history of diabetes, high cholesterol, heart attack or stroke2
  • you have gestational diabetes (diabetes during pregnancy) or prediabetes
  • you are overweight3
  • you have kidney disease
  • you have high blood pressure or cholesterol
  • you have previously had heart trouble or stroke
  • you have a heart condition such as atrial fibrillation.
  • 35 years
  • 45 years
If you have diabetes (type 1 or 2)
  • As part of your yearly diabetes review (both men and women)
If you have schizophrenia, major depressive disorder, bipolar disorder or other severe mental illness
  • 25 years (both men and women)

What’s my risk of a heart attack or stroke?

If you are 35 or older, check at what age you should start having a heart check.

Your doctor or nurse can help your work out what your current risk is and what you can do to lower your risk.

They will help you will identify what things in your life (risk factors) might be putting you at risk for a heart attack, stroke, or of developing diabetes.

Your risk is an estimate of how likely you are to have a heart attack or stroke in the next five years. If you have a 10% risk, this means that if there were 100 people with the same risk as you, we'd expect 10 of them to have a heart attack or stroke in the next 5 years.

How can I lower my risk of CAD?

No matter how high or how low your risk of heart disease is, there are always choices you can make to manage your risk and improve your heart health. 

Even a small change can have a positive impact on your risk of heart attack and stroke. The more you change the better. 

Learn more about:  

There are choices you can make today to better manage your coronary artery disease.

Learn more 

What happens during a heart attack? Heart Foundation, NZ 

References

  1. Ischemic heart disease National Heart, Lung, and Blood Institute, US
  2. What's my risk of a heart attack or stroke? Heart Foundation, NZ 

Reviewed by

Dr Hari Talreja is a renal physician/hypertension specialist with advanced training from Canada and a master’s degree from Harvard University in the USA. He is one of the very few American Society of Hypertension-certified hypertension specialists in New Zealand. He is the clinical lead for transplantation, hypertension and clinical research at Counties Manukau Health. He also practices at Ormiston Specialists Centre, Flatbush and Gilgit Road Specialist Centre, Epsom.
Credits: Health Navigator Editorial Team. Reviewed By: Dr Hari Talreja, Specialist Renal and Hypertension Services, Auckland Last reviewed: 22 Feb 2020