Angina

If a coronary artery becomes completely blocked, the section of heart muscle supplied by that artery will die, unless the blockage is relieved quickly. This is a heart attack, also called a myocardial infarction or MI. The pain is more severe and prolonged than angina and is not relieved by your usual angina treatment. If you are having a heart attack, you may also feel sick, breathless and sweaty, and may vomit. Sometimes, however, there are no symptoms at all. If you suspect that you, or someone else is having a heart attack, call for emergency help.

Causes

Angina is due to a narrowing of the coronary arteries - the vessels that supply the heart with blood. These arteries become furred up with fatty deposits, a process called atherosclerosis, leading to coronary heart disease.
As well as atherosclerosis, other rarer problems can also lead to angina, including:

• heart valve disease
• anaemia (a reduced amount of red blood cells in your blood)
• fast, abnormal heart rhythms
• diseases of the heart muscle
• a spasm or cramping of coronary arteries (see Variant angina)

Coronary heart disease, which is the main cause of angina, is more common in men than women. The likelihood of getting it increases as you get older. You are also more prone to getting coronary heart disease if you:

• have a high blood cholesterol level
• have high blood pressure
• have diabetes
• smoke
• do little physical activity

Angina can sometimes run in the family, so if a close relative has had angina, your risk of having it may be higher.

If you have noticed a pain in your chest when you exert yourself, you should visit your GP as soon as possible. Your GP will ask you a number of questions about the pain and then examine you. He or she will listen to your heart and chest, check your blood pressure, and look for any signs of anaemia.
If you develop a sudden pain in your chest, you should call for emergency help.

You may need to have some further tests to help diagnose if you have a heart condition. These can include:

• an ECG (electrocardiogram), where your hearts electrical activity is measured, either while you are lying down or exercising on a treadmill
• blood tests, such as a blood count, cholesterol and lipid levels, and cardiac enzymes (which are released by damaged heart cells)
• an echocardiogram, where an ultrasound probe is run over your chest so that the hearts chambers and valves can be seen working
• an angiogram, where a dye visible on X-rays is injected into your coronary arteries to show up any narrowing or blockages

Asthma cant be cured. Treatments aim to reduce the frequency, severity and length of asthma attacks. A lot of different factors are involved in asthma, so each treatment plan will be individual, combining medicines and asthma management in the way that works best for your child.

There are several practical steps that you can take to help prevent angina attacks and help stop your angina progressing to a heart attack.

• If you smoke, give up. Stopping smoking is difficult, so ask your GP or pharmacist for advice.
• If you are overweight, try to lose excess weight.
• Eat a low-fat, high-fibre diet, rich in fruit and vegetables.
• Try to eat oily fish, such as sardines or salmon, once a week.
• Drink alcohol in moderation
• Take regular exercise. Moderate aerobic exercise such as brisk walking, cycling or swimming is recommended. Get advice from your doctor or practice nurse on how much exercise you can do without any problems, and gradually increase it over time.
• Reduce stress where possible. You may find that learning relaxation techniques will help you with this.
• Attend regular check-ups with your doctor to monitor your blood pressure and get advice on how to reduce it if necessary.
• If you have diabetes, you should aim to closely control your blood sugar levels, as advised by your nurse or doctor.

Short-term treatment of symptoms

• Glyceryl trinitrate (GTN). This is a short-acting nitrate prescribed to provide relief during attacks. It comes as a spray (used in the mouth) or tablets (placed under the tongue) to take when an angina episode starts. It works by relaxing the coronary arteries so that more blood can flow through them and reach the heart muscle.
• Aspirin. If you have unstable angina, you will probably be given aspirin as soon as you are admitted to hospital, to help stop your blood from clotting and prevent a heart attack.
• Heparin. This is another medicine that prevents the blood from clotting. You will probably be given a heparin if you have unstable angina, while you are in hospital.

Long-term treatment for prevention of attacks

• Aspirin. You will probably be prescribed a small daily dose of aspirin if you have stable angina, as it lowers the risk of having a heart attack. However, aspirin increases your risk of stomach problems such as ulcers or indigestion, so its not suitable for everyone. Ask your GP for advice about whether you should take aspirin.
• Beta-blockers (e.g. atenolol, bisoprolol). These slow your heart rate and the pumping power of the heart. This reduces your hearts demand for oxygen. Beta-blockers are not suitable for people with asthma.
• Long-acting nitrates (e.g. isosorbide mononitrate). These widen the coronary arteries to improve blood flow to the heart. They are available as tablets or patches.
• Calcium-channel blockers (e.g. nifedipine). These relax the coronary arteries and other blood vessels, and reduce the force of the contraction of the heart.
• Potassium-channel activators (e.g. nicorandil). These relax coronary arteries to increase blood flow.
• Statins (e.g. simvastatin). These help reduce your cholesterol level, preventing fatty deposits in your coronary arteries from building up further.

For people with severe angina, the best treatment may be surgery or angioplasty.

• Angioplasty
  Angioplasty (also known as percutaneous coronary intervention or PCI). A miniature collapsed balloon is threaded through the blood vessels until it reaches the arteries of the heart. The balloon is inflated to widen the blocked coronary artery. A stent (flexible mesh tube) is sometimes inserted to help keep your artery open afterwards. Sometimes a coated stent is used as this releases a drug that helps to keep the blood vessel open.
• Coronary artery bypass graft
  Coronary artery bypass graft (CABG). Vessels from your legs or chest are used to bypass the blockage. This is open-heart surgery and requires a longer stay in hospital.

1. I have diabetes and I have heard this can give me angina. Do I need to take special precautions?

If you have diabetes, you have a higher risk of developing heart disease, and therefore angina. It's important that you monitor your blood glucose levels carefully and make sure that they are within recommended limits. Be more physically active, and if you smoke, stop. Have your blood cholesterol levels checked by your GP and try to reduce the levels of fat in your diet. Aim to have a healthy blood pressure (below 130/80mmHg) and try to lose any excess weight.

If you have diabetes, you're more likely than other people to have high blood pressure and high levels of cholesterol in your blood. Diabetes can also affect the heart muscle itself, making it a less efficient pump and making it more likely that you will develop heart disease and angina. So, if you have diabetes, your GP will probably prescribe medicines to treat some of the risk factors that you may have. For example, he or she may give you medicine to lower your blood cholesterol level or aspirin to reduce the risk of blood clotting. Your GP will also encourage you to stop smoking.

If you have high levels of both triglycerides (fats) and cholesterol in your blood, you have a greater chance of developing angina. The risk is particularly high if you also have a low level of high-density lipoprotein (HDL or "good" cholesterol), which is more likely if you have diabetes. You may need to take a medicine known as a statin, such as simvastin (Zovor), to reduce your cholesterol levels, and perhaps another, such as bezafibrate (eg Bezalip), to control your triglyceride levels. Cutting down on fats in your diet, particularly saturated fats (which are found mostly in meat and dairy products), will also help.

High blood pressure is common in people with diabetes and it's essential to control it. If you have diabetes, you should aim to have a blood pressure below 130/80mmHg, or lower than that if your kidneys are already damaged. You may be able to control your blood pressure by losing excess weight, doing more exercise and cutting down on alcohol and salt, although you may also need to take medicines, such as a beta-blocker. Your GP will be able to advise you on weight-loss programmes that are suitable for you.

Always ask your GP or pharmacist for advice and read the patient information leaflet that comes with your medicine.

Being physically active may help to reduce the amount of medicine or insulin you need to take for your diabetes, and can help reduce your risk of angina. It's important to monitor your blood glucose carefully as you start to build up your level of physical activity, because you may need to change the dose of your medication. Get advice from your GP or practice nurse on how much exercise you can do without any problems, and gradually increase it over time.

2. How can the fats in my food cause angina?

Fat is a good source of energy but eating too much of the wrong types of fat increases your risk of angina and other heart diseases.

Some fat is an essential part of a healthy diet but it's important that you don't eat too much fat and that you're careful of the type that you eat.

The fat in your blood is turned into cholesterol by your liver. The cholesterol then enters your blood to be transported around your body. Not all cholesterol is bad for you; there is a harmful form and a protective form. The harmful type of cholesterol is LDL or low-density lipoprotein (also known as "bad" cholesterol). The protective type of cholesterol is HDL or high-density lipoprotein (also known as "good" cholesterol).

You should reduce the amount of fat you eat to help reduce your cholesterol level. There are different types of fat in food.

• Saturated fats, which increase cholesterol levels. Examples of foods high in saturated fat include cake and biscuits, pastry, meat products and hard cheese.
• Mono-unsaturated fats, which help lower "bad" cholesterol levels. Examples of foods high in monounsaturated fats include olive oil and rapeseed oil.
• Polyunsaturated fats, which lower both harmful and protective cholesterol levels. Examples of foods high in polyunsaturated fats include sunflower oil and soya oil.

When you're shopping for food, compare the labels so you can pick those with less total fat or less saturated fat. Try to choose lower fat versions of dairy foods, such as semi-skimmed or skimmed milk, and reduced-fat yoghurt, whenever you can.

Cutting down on saturated fats and replacing them with small amounts of unsaturated fats can help to reduce your cholesterol level by up to one-tenth.

There is a particular type of polyunsaturated fat called omega-3 which can help to reduce your risk of heart disease and angina. You can get omega-3 fats from:

• ·oily fish such as kippers, mackerel, sardines and salmon
• certain oils such as rapeseed, walnut and linseed oil
• fish oil supplements

You should aim to eat at least one portion of oily fish per week.

3. I have been referred for a stress test. What is this?

An exercise tolerance test (stress test or exercise ECG) is a way of helping your doctor to confirm if you have angina and is particularly useful in determining if you need further tests. An electrocardiogram (ECG) is used to test your resting heart activity, but this can appear normal even if you have angina. A stress test usually involves you exercising on a treadmill or an exercise bike, while your heart activity is monitored by an ECG. Your doctor can also assess the severity of any symptoms of angina that develop during this exercise, which will help him or her to decide on the best treatment for you.

An exercise tolerance test (stress test) helps your doctor to confirm if you have angina and can also be used to determine if you need to have any further tests. Your doctor will only recommend that you have a stress test after he or she has asked you about your symptoms and given you a physical examination, including a resting ECG.

A resting ECG tests your how well your heart is working, but this can appear normal even if you have angina. When you exercise, you put stress on your heart and this can cause symptoms of angina to appear. If you're referred for a stress test, it typically involves you exercising on a treadmill or an exercise bike. This allows your heart activity to be monitored by an ECG during physical exercise. Your doctor can then assess the time taken before any ECG changes occur, how severe they are and how long it takes your heart to recover after you have stopped exercising. Other measurements taken will include the time taken for any symptoms of angina to develop, along with changes in your blood pressure and heart rate. Your doctor will be able to assess the severity of any symptoms of angina that you get during exercise, which will help him or her to decide on the best treatment for you.

Exercise stress testing can also be used to test how effective medicines are in controlling your symptoms of angina. They can help your doctor to recommend a suitable level of exercise for you after your symptoms are under control.

• The British Heart Foundation
  0300 330 3311
  www.bhf.org.uk

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