Focus on: Peripheral arterial disease

Arteries that can be affected by PAD

Peripheral arterial disease can cause pain when walking and can even have life-threatening consequences. Professor Julian Scott, Professor of Vascular Surgery at Leeds Teaching Hospitals NHS Trust and President of the Vascular Society of Great Britain and Ireland, explains why it develops and how you can reduce your risk.

What is peripheral arterial disease?

Peripheral arterial disease (PAD) – often called peripheral vascular disease – is a type of vascular disease (a form of cardiovascular disease primarily affecting the blood vessels). This often manifests as pain when walking. This is caused by the narrowing (stenosis) of the arteries in the legs, due to the gradual build-up of fatty material called atheroma within their walls – a condition called atherosclerosis. PAD can affect any artery in the body (excluding those that supply the heart) but it most commonly affects the arteries that supply the legs.

How common is PAD?

About one in five of over-60s in the UK have some form of PAD, which can have serious consequences if left untreated. Most people with PAD have history of smoking, hypertension (high blood pressure), hyperlipidaemia (raised cholesterol), coronary heart disease or diabetes.

How does PAD affect different parts of the body?

About seven in ten of PAD cases we see in vascular clinics are related to the legs, and about one in five is due to aneurysms such as an abdominal aortic aneurysm (AAA), which is when the vessel dilates and forms balloon-like swelling in the aorta wall. The carotid arteries can also be affected (read more about this), as can arteries that supply the liver, spleen, stomach and bowel. For unknown reasons, it rarely happens to the arteries in the arms.

What are the symptoms?

With AAA there are usually no symptoms, which is why the NHS national screening programme is so important

The symptoms of PAD vary depending on what part of the body is affected. In the legs, intermittent claudication (pain when walking) is the most common symptom. This is because when you’re resting, your legs receive enough blood flow, but when you start walking the calf muscles need more. The pain worsens as you walk faster or uphill, and usually stops when you rest for few minutes.

If an artery higher up is affected then there may be pain in the thighs or buttocks when walking.

With AAA there are usually no symptoms, which is why the NHS national screening programme is so important (see box below). When the arteries that supply the liver, spleen, stomach and bowel are affected, people tend to experience severe pain after eating, and they often lose significant amounts of weight as result.

AAA screening

If you are man aged over 65, you are at higher risk of an abdominal aortic aneurysm. That is why there is now an AAA Screening Programme in all parts of the UK. Screening involves an ultrasound scan that takes about ten minutes. Every 65-year-old man should be sent an invitation for aneurysm screening. You can also ask for a test, especially if you are older than 65 and haven’t had one. See the AAA screening website or call 01452 318844 (02890 631828 in Northern Ireland).

Women who are concerned about their risk of AAA should discuss it with their GP.

How is PAD diagnosed and what screening tests are used?

There are several tests that can help confirm diagnosis of PAD. GPs or practice nurses can perform quick and non-invasive test called the ankle brachial pressure index (ABPI). ABPI compares your blood pressure measured at your ankle with your blood pressure measured at your arm. If you have narrowing in your leg arteries, there’s likely to be lower blood pressure in your feet.

Other tests could include carotid and abdominal ultrasound to check for problems in the arteries in those areas. An angiogram and other types of imaging to show the arteries, such as computerised tomography angiogram (CTA), which uses contrast dye, or magnetic resonance angiogram (MRA), which uses magnetic resonance imaging, may also be carried out.

AAA is far more common in men than women and there is now a screening programme for 65-year-old men throughout the UK (see box above).

What are the risks of PAD?

People with PAD are more likely to suffer heart attack or stroke. If you have a large AAA (more than 5.5cm), there is risk it could burst and cause internal bleeding, which is an emergency situation. If the AAA does burst, you’d usually experience sudden, severe back pain and may also collapse.

People with PAD are more likely to suffer heart attack or stroke

If you have PAD with intermittent claudication, it’s important to go to the doctor as soon as possible if your leg pain suddenly becomes worse or the distance you can walk suddenly decreases. Early signs of critical limb ischaemia (persistent lack of blood flow to the leg, which can lead to gangrene and amputation) can include not being able to sleep at night because of the pain, or having to hang your leg over the side of the bed to relieve it. Someone with these symptoms should be seen by consultant vascular surgeon within 14 days. Critical limb ischaemia is uncommon, occurring in approximately 500 to 1,000 patients per million over the course of year.

About 1–3 per cent of all people with PAD and claudication will have to have an amputation, increasing to about 5 per cent in people with diabetes. It’s important to remember that if you develop critical limb ischaemia and are offered an amputation without any further investigations, such as CTA or MRA, you should seek second medical opinion to see if there’s anything else that can be done to improve things.

How can I reduce my risk?

PAD is a type of cardiovascular disease, so the usual measures such as stopping smoking, watching your weight, keeping active and maintaining healthy blood pressure and cholesterol levels can help. PAD can also be a hereditary condition, so if you have a family history of it, discuss it with your GP.

What treatment is available?

There’s no cure, so PAD treatments focus on improving the symptoms and quality of life. Treatments can slow the progression of the narrowing in the arteries and help reduce your risk of heart attack and stroke. You can help yourself by being physically active and managing your weight, blood pressure and cholesterol. If you smoke, it’s vital to stop, as smokers are prone to more aggressive forms of PAD.

Medication can include statins, anti-platelet medication such as aspirin, and ACE inhibitor medications, which help relax your blood vessels and improve blood flow.

In some cases, more invasive treatments may be required. For PAD in the leg, this can include angioplasty or surgery on the affected vessel to improve blood flow. There are two main treatments for an AAA that needs to be operated on: surgical repair or endovascular aneurysm repair (EVAR). Your vascular surgeon will discuss which treatment option is best for you.

Is there anything I can do to ease the leg pain caused by PAD?

Minimising risk factors and being physically active can make big difference. The important thing is to exercise to, and beyond, the point of pain. You should build up to minimum of 150 minutes of moderate-intensity physical activity week. It’s also important to vary the type of activity that you do.

Walking is a great way to build up your physical activity levels – remember that every ten minutes counts.

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