Coronary heart disease (CHD) is usually caused by a build-up of fatty deposits (atheroma) on the walls of the arteries around the heart (coronary arteries).
The build-up of atheroma makes the arteries narrower. This restricts the flow of blood to the heart muscle. This is called atherosclerosis.
Your risk of developing atherosclerosis is much higher if you:
- have high blood pressure (hypertension)
- have a high blood cholesterol level
- don't exercise often
- have diabetes
Other risk factors for developing atherosclerosis include:
- being obese or overweight
- having a family history of CHD
The risk is increased if you have a male relative under the age of 55, or a female relative under 65, with CHD.
Cholesterol is a fat made by the liver from the saturated fat in your diet. It's essential for healthy cells, but too much in the blood can lead to CHD.
High blood pressure
High blood pressure (hypertension) puts a strain on your heart and can lead to CHD.
Smoking is a major risk factor for coronary heart disease. Both nicotine and carbon monoxide (from the smoke) put a strain on the heart by making it work faster. They also increase your risk of blood clots.
If you smoke, you increase your risk of developing heart disease by 24%. This can lead to blocked arteries.
A high blood sugar level may lead to diabetes, which can more than double your risk of developing CHD.
It may cause the lining of blood vessels to become thicker, which can restrict blood flow.
A thrombosis is a blood clot in a vein or artery.
If a thrombosis happens in a coronary artery it prevents the blood supply from reaching the heart muscle. This may cause a heart attack.
Content supplied by the NHS and adapted for Ireland by the HSE