Cardiovascular diseases are diseases of the heart (cardiac muscle) or blood vessels (vasculature). However, in practice, when doctors use the term ‘cardiovascular disease’ they usually mean diseases of the heart or blood vessels that are caused by atheroma.
Patches of atheroma are like small fatty lumps that develop within the inside lining of arteries (blood vessels). Atheroma is also known as ‘atherosclerosis and ‘hardening of the arteries’. Patches of atheroma are often called ‘plaques’ of atheroma.
A patch of atheroma makes an artery narrower. This can reduce the blood flow through the artery. In time, patches of atheroma can become larger and thicker.
Sometimes, a patch of atheroma may develop a tiny ‘crack’ on the inside surface of the blood vessel. This may trigger a blood clot (thrombosis) to form over the patch of atheroma which may completely block the blood flow. Depending on the artery affected, a blood clot that forms on a patch of atheroma can cause a heart attack, a stroke, or other serious problems.
What are the cardiovascular diseases caused by atheroma?
Coronary heart disease
The term ‘heart disease’, or ‘coronary heart disease’, is used for conditions caused by narrowing of one or more of the coronary (heart) arteries by atheroma. The problems this can cause include angina, heart attack, and heart failure. Heart disease is common in the UK in people aged over 50.
Cerebrovascular disease – stroke and TIA
Cerebrovascular disease means disease of the arteries within the brain. The problems this can cause include a stroke or a TIA (transient ischaemic attack). A stroke means that part of the brain is suddenly damaged. The common cause of a stroke is due to an artery in the brain which becomes blocked by a blood clot (thrombus). The blood clot usually forms over some atheroma. A TIA is a disorder, a stroke like symptom, caused by temporary lack of blood supply to a part of the brain which usually resolves within 24 hours.
Peripheral vascular disease
Peripheral vascular disease is narrowing due to atheroma that affects arteries other than arteries in the heart or brain. The arteries that take blood to the legs are the most commonly affected.
If you can prevent a build-up of atheroma in the arteries, you are less likely to develop the above diseases. If you already have one of the above diseases, you may prevent or delay it from getting worse if you prevent further build-up of atheroma.
Risk factors
Everyone has some risk of developing atheroma. However, certain ‘risk factors’ increase the risk. Risk factors include:
lifestyle risk factors that can be prevented or changed:
- smoking
- lack of physical activity (a sedentary lifestyle)
- obesity
- an unhealthy diet and eating too much salt
- excess alcohol
treatable or partly treatable risk factors:
- hypertension (high blood pressure)
- high cholesterol blood level
- low levels of good cholesterol
- diabetes
- kidney diseases causing diminished kidney function
fixed risk factors – ones that you cannot alter:
- a strong family history. This means if you have a father or brother who developed heart disease or a stroke before they were 55, or in a mother or sister before they were 65 years of age
- being male
- an early menopause in women
- age. The older you become, the more likely you are to develop atheroma
- ethnic group. For example, people who live in the UK with ancestry from India, Pakistan, Bangladesh, or Sri Lanka have an increased risk
However, if you have a fixed risk factor, you may want to make extra effort to tackle any lifestyle risk factors that can be changed.
Note: some risk factors are more ‘risky’ than others. For example, smoking probably causes a greater risk to health than obesity. Also, risk factors interact. So, if you have two or more risk factors, your health risk is much more increased than if you just have one. For example, a middle aged male smoker who does little physical activity and has a strong family history of heart disease has quite a high risk of developing a cardiovascular disease such as a heart attack or stroke before the age of 60.
Research is looking at some other factors that may be risk factors. For example, high blood levels of fibrinogen, C reactive protein, apolipoprotein B, and homocysteine are being investigated as possible risk factors.
