Coronary heart disease

Coronary heart disease is a condition in which fatty deposits build up in the walls of the arteries to your heart, which causes them to narrow. This can reduce the supply of oxygen to your heart, which may cause angina (pain in your chest) and over time can lead to a heart attack.

About coronary heart disease

Your heart is a pump that circulates blood to your lungs and the rest of your body. It supplies your body with oxygen and nutrients and takes away carbon dioxide and waste products. Your heart also needs a supply of blood and this is provided by blood vessels called coronary arteries.

Coronary heart disease happens when fat and cholesterol in your blood builds up in your artery walls and forms a plaque or atheroma. This is known as atherosclerosis. The plaque can prevent your heart muscle from getting the blood supply it needs.

Sometimes the plaque may rupture (break open) and a blood clot forms on the surface of the plaque. This can stop an area of your heart muscle receiving blood and oxygen, which can lead to a heart attack. Heart muscle damage can result in abnormal heart rhythms which can cause cardiac arrest where your heart stops beating altogether, which is fatal. In the UK, more people die from coronary heart disease than from any other cause.

How atherosclerosis develops

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Symptoms of coronary heart disease

Coronary heart disease develops slowly over many years. In some people, breathlessness when exercising is the only symptom. You may not know anything is wrong until you develop chest pains (angina) or have a heart attack.

Angina

Angina usually happens if the blood flow in the arteries that supply your heart is restricted.

Angina typically starts when you're exerting yourself physically or feeling upset. It can also be brought on by cold weather or after a meal. Symptoms include:

• discomfort or a tightening across your upper chest
• pain that spreads to your neck, jaw, throat, back or arms
• breathlessness or a choking sensation
• sweating

Angina usually lasts for a few minutes and disappears quickly after you rest.

Heart attack

A heart attack can cause severe pain in the centre of your chest, which may feel like very bad indigestion, or you can have mild pain and feel unwell. Symptoms can happen suddenly, but sometimes the pain can develop more slowly. Symptoms include:

• a feeling of heaviness, squeezing or crushing in the centre of your chest
• pain that may spread to your arms, neck, jaw, face, back or stomach
• feeling dizzy
• feeling breathless
• feeling sick or vomiting

It’s possible that you may not have any symptoms. This is called a silent myocardial infarction.

Call for emergency help immediately if you suspect you or a person you’re with is having a heart attack. If it’s to hand, take an aspirin to chew, or swallow it dissolved in water (provided you aren’t allergic to aspirin). This will help to prevent the clot that is blocking the coronary artery from growing.

Arrhythmia

An arrhythmia is an irregular heartbeat, which you may feel as a heart palpitation (a sensation of a skipping or thumping heart beat).

Heart failure

Over time, coronary heart disease may weaken your heart, and lead to heart failure. Heart failure means your heart isn't strong enough to pump blood around your body effectively and you get tired and out of breath easily. It can also cause swelling in your ankles and legs.

Causes of coronary heart disease

Coronary heart disease is caused by a build up of fatty deposits on your artery walls.

Coronary heart disease is more common in older people (men over 45 years and women over 55). It's also more common among people from South Asia. Other factors that increase your risk of developing coronary heart disease include:

• smoking
• being overweight, especially if you have excess fat around your tummy
• an inactive lifestyle
• diabetes
• high blood pressure
• high cholesterol
• drinking excessive amounts of alcohol
• a family history of heart disease
• eating an unhealthy diet, such as foods that are high in saturated fat, cholesterol, sodium (salt) and sugar

Diagnosis of coronary heart disease

Your GP will ask about your symptoms and examine you. He or she may also ask you about your medical history. You may have one or more of the following tests.

• Blood tests can check the levels of certain fats, cholesterol, sugar and proteins in your blood.
• An electrocardiogram (ECG) is a test that measures the electrical activity of your heart to see how well it's working. However, an ECG can be normal even in the presence of coronary artery disease.
• An exercise ECG, in which you will have the test while you walk on a treadmill or pedal on an exercise bike. This may be combined with a radionuclide test.
• In a radionuclide test, your doctor will give you a small, harmless injection of radioactive material, which will pass through your heart muscle. A large camera will be directed at your heart that will pick up rays sent out by the radioactive material and show the flow of blood through your heart.
• An echocardiogram is a test that uses ultrasound to produce a moving 'real-time' image of the inside of your heart. It gives information about the pumping action and structure of your heart. A stress echocardiogram is done while your heart is under stress.
• A coronary angiogram is a test in which your doctor will inject a special dye into the blood vessels of your heart to make them clearly visible on X-ray images.
• A chest X-ray will provide an overall image of your heart and lungs.
• A CT scan can give a measure of the amount of calcium in your arteries, which can indicate coronary heart disease.
• An MRI scan uses magnets and radio waves to produce images of the inside of your body. It’s used increasingly to examine the heart for signs of coronary heart disease.
• In an electrophysiological test, your doctor will put a catheter into a blood vessel in your groin and guide it to your heart. The tip of the catheter will stimulate your heart and record the electrical activity.

Treatment of coronary heart disease

Your treatment for coronary heart disease will depend on how serious it is. There are several treatments available.

Self-help

Your doctor may advise you to make certain lifestyle changes to reduce your symptoms or prevent a heart attack, but this on its own won’t be enough. See Prevention.

Medicines

Medicines aim to stop coronary heart disease getting worse or prevent future heart attacks. Examples include the following.

• Anti-platelet medicines, such as aspirin (a small 75mg daily dose), make your blood less likely to form clots and reduce your risk of having a heart attack.
• Cholesterol-lowering medicines, such as statins, slow down the process of atherosclerosis.
• Beta-blockers slow your heart rate and reduce the amount of work your heart has to do. They can also help control your heart rhythm.
• ACE inhibitors lower your blood pressure and are often used if you have heart failure or after a heart attack.
• Angiotensin II receptor blockers are an alternative to ACE inhibitors.
• Calcium-channel blockers relax and widen your arteries.
• Anticoagulants help to stop blood clots forming.
• Nitrates relax your coronary arteries and allow more blood to reach your heart.
• Antiarrhythmic medicines help to control your heart rhythm.

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

Non-surgical treatment

A coronary angioplasty can widen your narrowed coronary artery. Your doctor will pass a collapsed balloon through your blood vessels until it reaches the arteries of your heart and then inflate it. He or she may insert a stent (flexible mesh tube) to help keep your artery open.

Surgery

Your surgeon may recommend a coronary artery bypass graft (CABG). In this operation he or she will take a piece of a blood vessel from your leg or chest and use it to bypass the narrowed coronary arteries. This can improve the flow of blood to your heart.

Prevention of coronary heart disease

You can usually prevent coronary heart disease by adopting a healthy lifestyle. This includes:

• not smoking
• losing excess weight
• doing regular physical activity – aim to do 150 minutes of moderate exercise each week but stop exercising if you feel any pain or discomfort
• eating a healthy balanced diet
• not exceeding three to four units of alcohol a day for men or two to three units for women

Produced by Rebecca Canvin, Bupa Health Information, June 2012.

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

For sources and links to further information, see Resources.