Angina

Published by Bupa's Health Information Team, May 2011.

This factsheet is for people who have angina, or who would like information about it.

Angina describes the pain or discomfort felt in the chest when the flow of oxygen-rich blood in a coronary artery (a blood vessel that supplies the heart with blood) is restricted.

About angina

Angina is a symptom of coronary heart disease and affects about two million people in the UK. You’re more likely to get angina as you get older and men are more likely to get it than women. Angina usually starts with chest pain or tightness when you’re under stress or doing some sort of physical activity.

Types of angina

There are two main types of angina.

Stable angina

Stable angina is when you get regular or predictable symptoms that you have had for more than two months. Symptoms of stable angina usually develop gradually over time and you can often notice a pattern to your symptoms. For example, it’s common to only get symptoms when you do physical activity or if you’re under a lot of stress. Symptoms of stable angina that get worse with physical activity often pass within a few minutes of rest.

Unstable angina

Unstable angina is usually caused by sudden narrowing of a coronary artery and can mean you’re at risk of having a heart attack or stroke. Symptoms of unstable angina often come on after only a small amount of effort or even when resting. There is often no pattern to your symptoms and they may last for 30 minutes or more. Pain and discomfort may develop quickly and be more severe and frequent than with stable angina. If you get sudden chest pain or you think you may have unstable angina, call for emergency help immediately.

Angina and heart attack

If a coronary artery becomes completely blocked, part of the heart muscle may be starved of oxygen and become damaged. This is a heart attack. The pain is usually severe and lasts longer than that of angina. If you have angina, your usual treatment may not relieve the pain of a heart attack. If you suspect that you, or someone else, is having a heart attack, call for emergency help immediately.

Symptoms of angina

Angina is often brought on by physical activity, emotional stress, cold weather or after a meal. If you have angina, you may have the following symptoms.

• Pain and discomfort in your chest. This pain can feel dull, heavy, tight or severe.
• Pain and discomfort that may spread to your jaw, neck, arms, back or stomach.
• Palpitations, sweating, feeling sick or shortness of breath.

Symptoms of angina may vary depending on the type of angina you have. Some people may get very few symptoms, which can make a heart attack difficult to spot.

If you have stable angina and your symptom patterns change, see your GP as soon as possible. If you get angina symptoms at rest, call for emergency help immediately.

Complications of angina

People with angina are more likely to have:

• a heart attack or stroke
• anxiety or depression
• poor quality of life – it may be harder to carry out everyday activities

Causes of angina

Stable angina is caused by narrowing of the coronary arteries. Gradually over time, fatty deposits build up on the walls of the coronary arteries and they become narrowed and hardened. This restricts blood flow to your heart and is known as atherosclerosis, which is the cause of coronary heart disease.

Unstable angina is caused when a fatty deposit (plaque) bursts (ruptures) and a blood clot forms around the plaque. This can partially or completely block a coronary artery and suddenly reduce blood flow to part of your heart.

The main cause of angina is coronary heart disease. You’re more likely to get coronary heart disease if you:

• have high blood pressure
• have diabetes
• have high cholesterol
• smoke
• have an inactive lifestyle
• are overweight
• have a family history of coronary heart disease

As well as coronary heart disease, other rarer problems can also lead to angina, including:

• heart valve disease
• anaemia (a reduced amount of red blood cells in your blood)
• heart muscle disease (cardiomyopathy)
• an irregular heart beat (arrhythmia)

Animation - how atherosclerosis develops

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Diagnosis of angina

If you get pain or discomfort in your chest when you do physical activity, see your GP as soon as possible. Your GP will ask you about your symptoms and examine you. He or she may also ask you about your medical history.

If you get sudden pain in your chest that is still present at rest, call for emergency help immediately.

When you arrive at hospital you will have some tests, which may include the following.

• A physical examination – this includes measuring your blood pressure and monitoring your heart rate.
• Blood tests, such as a blood count (the number of various blood cells in your blood), glucose and cholesterol level and specific blood tests for heart damage (eg troponin).
• An ECG – this records the electrical activity of your heart, and helps to diagnose any potential or complete blockages in your coronary arteries. This can also be done when you exercise.
• Radionuclide tests – your doctor will give you a small, harmless injection of radioactive material, which passes through your heart muscle. A large camera directed at your heart picks up rays sent out by the radioactive material and creates an image of your heart.
• A coronary angiogram – a test that uses an injection of a special dye into the blood vessels to make them clearly visible on X-ray images.
• A CT scan uses X-rays to make a three-dimensional image of your heart.
• An MRI scan uses magnets and radiowaves to produce images of the inside of your body.

Treatment of angina

You may be able to control your angina by making lifestyle changes and taking medication. Any conditions you have that are causing your angina, such as high blood pressure, will be treated as well as your angina symptoms.

Self-help

There are many things you can do to help control your symptoms and stop your angina from causing further heart problems.

• If you smoke, stop. Ask your GP or pharmacist for advice.
• If you're overweight, try to lose excess weight.
• Eat a healthy, balanced diet that is low in saturated fat, salt and sugar and high in fibre, fruit and vegetables.
• Try to eat oily fish, such as sardines or salmon, once a week.
• Take regular exercise. Moderate aerobic exercise such as brisk walking, cycling or swimming is recommended. Get advice from your GP or nurse on how much exercise you can do.
• Don't exceed four units of alcohol a day for men or three units a day for women.
• Reduce stress where possible. You may find learning relaxation techniques will help you with this.
• Attend regular check-ups with your GP to monitor your blood pressure and cholesterol levels.
• If you have diabetes, it's important to closely control your blood sugar levels as advised by your GP or nurse.

Medicines

You may be prescribed medicines that can provide you with immediate relief from your symptoms.

• Glyceryl trinitrate (also known as GTN) is a medicine that works by widening your coronary arteries so that more blood can flow to your heart. It commonly comes as a spray (used in your mouth) or it can come as a tablet that you dissolve under your tongue. If glyceryl trinitrate doesn't relieve your chest pain after 15 minutes, or if the pain comes back, call for emergency help.
• If you have unstable angina, you will probably be given aspirin as soon as you get to hospital. This prevents your blood from clotting and reduces your risk of having a heart attack.
• Heparin is another medicine that prevents your blood from clotting. It's likely you will be given heparin injections if you have unstable angina when you're in hospital.

You may also be given regular medicines to help control your symptoms and to try to prevent you from having further heart problems, such as a heart attack. You may be given more than one medicine.

• Aspirin. If you have stable angina, you may be prescribed a small daily dose of aspirin to reduce your risk of having a heart attack. However, aspirin may increase your risk of stomach problems, such as ulcers, so it's not suitable for everyone. Speak to your GP for advice about taking aspirin.
• Angiotensin-converting enzyme (ACE) inhibitors (eg rampiril). These widen the coronary arteries to increase blood flow to your heart and help lower blood pressure.
• Beta-blockers (eg atenolol). These slow your heart rate and the pumping action of your heart. This reduces your heart's demand for oxygen. Beta-blockers may not be suitable if you have asthma.
• Statins (eg simvastatin). These help to lower your cholesterol level and prevent fatty deposits building up in your coronary arteries. You may be given these even if your cholesterol level is normal to help prevent a heart attack.
• Clopidogrel. This is an antiplatelet medicine to help prevent your blood from clotting.
• Potassium-channel activators (eg nicorandil). These relax coronary arteries to increase blood flow.
• Calcium-channel blockers (eg nifedipine). These relax the coronary arteries and other blood vessels, and reduce how strongly your heart beats.
• Long-acting nitrates (eg isosorbide mononitrate). These widen the coronary arteries and increase blood flow to the heart. They are available as tablets or patches. If you take these too often, you can reduce their effectiveness so it’s important to follow your GP or pharmacist’s advice on how to take this medicine.

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

Surgery

If you have severe angina, you may need to have a procedure called a coronary angioplasty or surgery.

Coronary angioplasty

This helps to improve blood flow to your heart and relieve the symptoms of angina. A coronary angioplasty widens your arteries by inflating a balloon in the narrowed or blocked coronary artery. A wire mesh tube called a stent is usually inserted to hold the coronary artery open.

Coronary artery bypass graft (CABG)

CABG is a type of surgery that involves taking a section of a blood vessel (graft) from your chest, leg or arm and attaching it to the affected coronary artery. This diverts the flow of blood around the narrowed or blocked coronary artery.

Prevention of angina

Most people can prevent angina by adopting a healthy lifestyle. This includes:

• not smoking
• losing excess weight
• doing 150 minutes (two and a half hours) of moderate exercise over a week in bouts of 10 minutes or more, for example by carrying out 30 minutes on at least five days each week or 75 minutes of vigorous intensity activity
• eating a low-fat, high-fibre diet with five portions of fruit and vegetables a day
• not drinking more than four units of alcohol a day for men and three units for women

For answers to frequently asked questions on this topic, see Common questions.

For sources and links to further information, see Resources.