All about blocked arteries

Professor Martin Bennett

The build-up of fatty deposits in the arteries is a potential silent killer. In this exclusive interview, June Davison talks to BHF Professor Martin Bennett about the condition.

BHF Professor Martin Bennett works at the University of Cambridge, researching why people develop atherosclerosis. His team is also developing new imaging techniques to better predict who might have a related event. He is also a consultant cardiologist and works at Addenbrookes and Papworth Hospitals.

Why do arteries become narrow?

Blocked arteries, also known as Atherosclerosis, is the build-up of fibrous and fatty material inside the arteries and is the underlying condition that causes coronary heart disease and other circulatory diseases. Atherosclerosis can affect all of the arteries, but particularly those that supply blood to the heart (coronaries), the neck arteries that supply blood to the brain (carotids), and the arteries that supply the legs (peripheral). This can ultimately bring on symptoms such as chest pain (angina) or lead to life-threatening conditions such as a heart attack or stroke.

What causes atherosclerosis?

The most dangerous outcome of atherosclerosis occurs if the plaque ruptures

Fatty material (or atheroma) starts accumulating in the lining of the artery wall from when we are quite young. The material is ‘foreign’ to our bodies, so causes inflammation. The artery tries to clear up the inflammation by repairing the tissue, creating a seal of fibrous material over the fatty core.

Over time, this forms a plaque, which consists of the fatty material, the inflammation and the fibrous tissue around it. This process gradually continues so more atheroma accumulates, causing more inflammation, which results in a bigger plaque. It can take many years before plaque growth has a significant effect.

What are the potential consequences of atherosclerosis?

The disease can be silent for many decades. But once the plaque gets to a certain size, the artery can become so narrowed that insufficient blood gets through, which can cause pain or discomfort, usually during exercise.

This can happen either in the chest (angina) due to lack of blood getting to the heart, or in the calves (claudication) due to lack of blood to the legs.

The most dangerous outcome of atherosclerosis occurs if the plaque ruptures (breaks down). The blood flowing over the top of the plaque can clot, causing a blockage in the artery that can result in a heart attack, or it can be carried downstream causing a stroke.

Isn’t atherosclerosis a natural part of the ageing process?

Atherosclerosis illustration

Atherosclerosis, which causes diseases of the arteries, is a very common process. One of the biggest risk factors for atherosclerosis is age, so it is more common among people in their 60s and 70s, although there are many elderly people who don’t have significant atherosclerosis.

The first evidence of atherosclerosis can appear quite early in life in people in their 20s and 30s, but it often doesn’t cause any problems at this stage and there may be a very long period where the disease is silent. Having risk factors for atherosclerosis and an unhealthy lifestyle mean you’re more likely to develop the disease at a younger age. The major message is look at your lifestyle and see if there are any changes you can make to reduce your risk.

How would I know if my arteries are blocked?

Many people with blocked arteries or atherosclerosis are unaware that they have it until they develop symptoms, such as angina or claudication. Unfortunately, sometimes the first time that someone realises that they have atherosclerosis is when they have an event such as a stroke or a heart attack.

Can I have a test for it?

We recommend that people over 40 go for a cardiovascular risk assessment or health check at their GP surgery. Your blood pressure, cholesterol and a medical history are all taken to calculate your risk of having an event such as a heart attack or stroke. Your GP or nurse can tell if you would benefit from lifestyle changes or treatment.

If you’re found to be at high risk of having an event, you’ll be advised to make changes to your lifestyle and be monitored. It’s also likely that you’ll be recommended to take drugs, such as a statin, to reduce your risk

Can atherosclerosis be reversed or slowed down?

Leading a healthy lifestyle and managing your risk factors is vital to slow the disease’s progression

The disease is progressive, and, unfortunately, current treatments can’t melt it away. However, there are things that can be done to slow its development and dramatically reduce the chances of a heart attack or stroke.

For example, medication can slow down how quickly the fatty material accumulates. Drugs can also stabilise the plaque and reduce the chance of it rupturing, so you’re much less likely to have a stroke or heart attack.

Leading a healthy lifestyle and managing your risk factors is vital to slow the disease’s progression. This will help to prevent the onset of symptoms such as angina and also reduce the risk of having an event.

How are blocked arteries treated?

Almost everyone who has had a heart attack or has been diagnosed with angina will be prescribed medication to help protect their heart. These drugs include aspirin, which reduces the stickiness of platelets to prevent blood clots from developing, and drugs to reduce cholesterol, usually statins.

Depending on their specific condition, some people may be prescribed additional treatment. For example, if someone has a heart attack, they’re likely to be prescribed beta blockers and an ACE inhibitor, as evidence shows these medicines can reduce the risk of a further heart attack.

Once someone has had an event or if they develop symptoms, they will be investigated to see if they need further treatment. They might have their neck scanned to see if they have carotid disease, a coronary angiogram to look at their coronary arteries, or they may have a scan or an angiogram of their legs to look at the extent of their leg disease.

Is there any other treatment that I can or should have?

Further treatment depends on how severe the disease is in the artery, how many arteries are involved, and how bad someone’s symptoms are.

For instance, if you have disease in the heart arteries, particularly if you are experiencing symptoms such as chest pains or shortness of breath, then it might be treated with an angioplasty and stent.

Or if you have narrowings in multiple coronary arteries, you may be recommended to have coronary bypass graft surgery. Similarly, significant narrowings in the legs or pelvis arteries can be treated with angioplasty and stenting or occasionally bypass surgery.

If you have significant disease in one or both of the carotid arteries in the neck, these are sometimes treated by surgery.

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