Coronary heart disease: The basics

Coronary heart disease is a leading cause of death in Australia.¹

Unfortunately, the first sign of the disease is often a heart attack. And because symptoms can go unrecognised, you can live with it for years without realising it.

However, while the warning signs of coronary heart disease may be hard to detect, there are plenty of things you can do to reduce your risk.

Coronary heart disease occurs when the blood supply to your heart is reduced or blocked by fatty deposits inside the walls of your coronary arteries. When blood flow to the heart is partially blocked, it can cause a chest pain known as ‘angina’.

A heart attack occurs when a coronary artery gets completely blocked and blood stops flowing to part of the heart. Without blood flow, the affected heart muscle is starved of the oxygen it needs to survive.

Coronary heart disease often takes decades to develop.

A thickening or hardening of the arteries is one of the main causes. This is a complex process that occurs with ageing and other uncontrollable factors. But it can be accelerated by things like:

• high blood pressure
• being overweight or obese
• smoking
• physical inactivity
• poor diet
• diabetes
• high cholesterol.²

High cholesterol is the result of too much ‘bad’ (LDL) cholesterol in your blood, which causes a build-up of fatty deposits inside your arteries.

‘Good’ (HDL) cholesterol, on the other hand, can help mop up the bad cholesterol and prevent it from building up in your arteries, reducing your chances of developing coronary heart disease.

Eating certain foods (while avoiding ones high in trans and saturated fats) can help lower your cholesterol. Some good-cholesterol foods include:

• oats
• whole-wheat products
• nuts (like walnuts and almonds)
• legumes (like peas, beans, lentils and chickpeas).

The same process that affects the blood vessels in your heart can also affect blood vessels in other parts of your body. For this reason, thickening or hardening of your body’s arteries can also cause:

• cerebrovascular disease. This affects the blood vessels that feed your brain. If an artery in the brain ruptures or gets blocked, it can cause a stroke
• peripheral artery disease. When the arteries in your legs become clogged, you might experience pain (usually in the calves) when walking. This can reduce mobility and, in severe cases, require an amputation
• aneurysm. This unusual bulging is the result of an artery wall filling up with blood and, sometimes, bursting. It can happen when the artery wall is weakened or damaged from conditions like high blood pressure.

Coronary heart disease can start to develop at a young age and worsen over time. The best protection against developing the disease is to know your risk factors.

As well as the modifiable risks mentioned above (such as smoking), risk factors that you can’t change include:

• a family history of coronary heart disease
• age (your risk increases after 45)
• ethnicity (Māori, Pasifika people and those from South Asian countries are at higher risk of heart disease)
• biological sex (men have a higher risk than women)
• being post-menopausal
• living with a severe mental illness.²

However, there are plenty of things you can do to help reduce your risk. These include:

• eating a wide range of nutritious foods that support heart health
• avoiding foods with saturated fat, added salt and added sugars, plus alcohol
• exercising regularly, aiming for 30 minutes of moderate activity (like swimming or a brisk walk) each day
• maintaining a healthy weight
• not smoking
• staying on top of health conditions like diabetes, high blood pressure and high cholesterol.

It’s always a good idea to see your GP regularly for a health check. This is an opportunity to get ahead of any potential health problems, including those affecting your heart.

The Heart Foundation provides information and resources about heart disease.