Coronary artery disease

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

Key points about coronary artery disease

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.
Coronary artery disease and stroke are the number one causes of death and disability in New Zealand.
There are a number of factors that are known to increase your risk of CAD.
The age when you are advised to start having heart checks changes, depending on your age, ethnicity and other risk factors.

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.

One in 20 adults have been diagnosed with heart disease. That's more than 165,000 New Zealand adults.

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.

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.

Men	Women
^{1. South-Asian peoples: Indian, including Fijian Indian, Sri Lankan, Afghan people, 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)}
If you have no known risk factors
45 years	55 years
If you are Māori, Pacific Peoples 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)

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.

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(external link).

Key practice points:

Communicating risk to patients as part of shared decision-making and CVD risk management is recommended
Start cardiovascular risk assessment earlier in patients of Māori, Pacific or South-Asian ethnicity: at age 30 years for males and age 40 years for females
Lifestyle recommendations to reduce cardiovascular risk are recommended for everyone
The 2018 CVD consensus statement recommendations on when to introduce pharmacological treatment can be followed by using existing calculations of low, intermediate and high risk.
New clinical high risk groups (>15% five-year risk), who require intensive management, include patients with:
- Congestive heart failure (CHF)
- Asymptomatic carotid or coronary disease
- An eGFR < 30 mL/min/m2 or < 45 mL/min/m2 in patients with diabetes
Patients with severe mental illness are considered a high risk group and CVD risk assessment from age 25 years is recommended

The immediate management of acute coronary syndromes in primary care(external link) BPAC NZ, 2015
Assessing cardiovascular risk in people with high clinical risk factors(external link) BPAC NZ, 2012