What is coronary heart disease?
Coronary heart disease (CHD), sometimes called ischaemic heart disease, is one of the world's biggest killers. About 1 in 5 men and 1 in 8 women die from the disease.
CHD generally affects more men than women, but from the age of 50 the chances of developing CHD are similar for men and women.
As well as angina (chest pain), the main symptoms of CHD are heart attacks and heart failure. However, not everyone has the same symptoms and some people may not have any before CHD is diagnosed.
About the heart
The heart is a muscle about the size of your fist. It pumps blood around your body and beats approximately 70 times a minute. After the blood leaves the right side of the heart, it goes to your lungs, where it picks up oxygen.
The oxygen-rich blood returns to your heart and is then pumped to the organs of your body through a network of arteries. The blood returns to your heart through veins before being pumped back to your lungs again. This process is called circulation.
The heart gets its own supply of blood from a network of blood vessels on the surface of your heart, called coronary arteries.
Why does coronary heart disease happen?
Coronary heart disease is the term that describes what happens when your heart's blood supply is blocked or interrupted by a build-up of fatty substances in the coronary arteries.
Over time, the walls of your arteries can become furred up with fatty deposits. This process is known as atherosclerosis and the fatty deposits are called atheroma.
Atherosclerosis can be caused by lifestyle habits and other conditions, such as:
Diagnosing coronary heart disease
If your doctor feels you're at risk of CHD, they may carry out a risk assessment. This involves asking about your medical and family history, your lifestyle and taking a blood test.
Further tests may be needed to confirm a diagnosis of CHD, including:
Read more about diagnosing coronary heart disease.
Treating coronary heart disease
Although coronary heart disease cannot be cured, treatment can help manage the symptoms and reduce the chances of problems such as heart attacks.
If you have problems such as a heart attack, or have any heart surgery, it is possible to eventually resume your normal life.
Advice and support is available to help you deal with aspects of your life that may have been affected by CHD.
By making some simple lifestyle changes, you can reduce your risk of getting CHD. These include:
- eating a healthy, balanced diet
- being physically active
- giving up smoking
- controlling blood cholesterol and sugar levels
Coronary heart disease symptoms
The most common symptoms of coronary heart disease (CHD) are chest pain (angina) and a heart attack.
You can also experience other symptoms, such as palpitations and unusual breathlessness. In some cases, people may not have any symptoms before they are diagnosed.
If your coronary arteries become partially blocked, it can cause chest pain (angina).
This can be a mild, uncomfortable feeling similar to indigestion. However, a severe angina attack can cause a painful feeling of heaviness or tightness, usually in the centre of the chest, which may spread to the arms, neck, jaw, back or stomach.
Angina is often triggered by physical activity or stressful situations. Symptoms usually pass in less than 10 minutes and can be relieved by resting or using a nitrate tablet or spray.
If your arteries become completely blocked, it can cause a heart attack (myocardial infarction).
Heart attacks can cause permanent damage to the heart muscle and, if not treated straight away, can be fatal.
If you think you're having a heart attack, call for immediate medical assistance.
Although symptoms can vary, the discomfort or pain of a heart attack is usually similar to that of angina, but it is often more severe. During a heart attack you may also experience the following symptoms:
The symptoms of a heart attack can be similar to indigestion. For example, they may include a feeling of heaviness in your chest, a stomach ache or heartburn. However, these symptoms can also be accompanied by a pain that affects the arms (particularly the left arm), the neck and the jaw.
A heart attack can happen at any time, including while you are resting. If the pain lasts longer than 15 minutes, it may be the start of a heart attack.
Unlike angina, the symptoms of a heart attack are not usually relieved using a nitrate tablet or spray.
In some cases, you may have a heart attack without any symptoms, called a silent myocardial infarction. This is more common in people with diabetes.
Heart failure can also occur in people with CHD when the heart becomes too weak to pump blood around the body, which can cause fluid to build up in the lungs that makes it increasingly difficult to breathe.
Heart failure can happen suddenly (acute heart failure) or gradually over time (chronic heart failure).
Coronary heart disease causes
Coronary heart disease (CHD) is usually caused by a build-up of fatty deposits on the walls of the arteries around the heart (coronary arteries).
The fatty deposits, called atheroma, are made up of cholesterol and other waste substances.
The build-up of atheroma on the walls of the coronary arteries makes the arteries narrower and restricts the flow of blood to the heart. This process is called atherosclerosis. Your risk of developing atherosclerosis is significantly increased if you:
- have high blood pressure
- have a high blood cholesterol level
- do not take regular exercise
- have diabetes
Other risk factors for developing atherosclerosis include:
- being obese or overweight
- having a family history of CHD – the risk is increased if you have a male relative with CHD under 55 or a female relative under 65
Cholesterol is a fat made by the liver from the saturated fat that we eat. Cholesterol is essential for healthy cells, but if there's too much in the blood it can lead to CHD.
Cholesterol is carried in the bloodstream by molecules called lipoproteins. There are several different types of lipoproteins, but 2 of the main ones are low-density lipoproteins (LDL) and high-density lipoproteins (HDL).
LDL, often referred to as bad cholesterol, takes cholesterol from the liver and delivers it to cells. LDL cholesterol tends to build up on the walls of the coronary arteries, increasing your risk of heart disease.
HDL, often referred to as "good cholesterol", carries cholesterol away from the cells and back to the liver, where it is broken down or passed from the body as a waste product.
High blood pressure
High blood pressure (hypertension) puts a strain on your heart and can lead to CHD.
Blood pressure is measured at 2 points during the blood circulation cycle. The systolic pressure is a measure of your blood pressure as the heart contracts and pumps blood out. The diastolic pressure is a measure of your blood pressure when your heart is relaxed and filling up with blood.
Blood pressure is measured in terms of millimetres of mercury (mmHg). When you have your blood pressure measured, the systolic pressure is the first, higher number to be recorded. The diastolic pressure is the second, lower number to be recorded. High blood pressure is defined as a systolic pressure of 140mmHg or more, or a diastolic pressure of 90mmHg or more.
Smoking is a major risk factor. Carbon monoxide (from the smoke) and nicotine both put a strain on the heart by making it work faster. They also increase your risk of blood clots.
Other chemicals in cigarette smoke damage the lining of your coronary arteries, leading to furring of the arteries. If you smoke, you increase your risk of developing heart disease by 24%.
While a high blood sugar level doesn't directly increase the risk of developing CHD, it may lead to diabetes, which can more than double your risk of developing CHD.
Diabetes can lead to CHD because it may cause the lining of blood vessels to become thicker, which can restrict blood flow.
A thrombosis is a blood clot within an artery (or a vein). If a thrombosis occurs in a coronary artery (coronary thrombosis), it will cause the artery to narrow, preventing the blood supply from reaching the heart muscle. This increases your chance of having a heart attack. Coronary thrombosis usually happens at the same place that the atherosclerosis is forming (furring of the coronary arteries).
Diagnosing coronary heart disease
Coronary heart disease (CHD) is usually diagnosed after a risk assessment and some further tests.
If your doctor thinks you may be at risk of developing CHD, they may carry out a risk assessment for cardiovascular disease, heart attack or stroke.
Your doctor will ask about your medical and family history, check your blood pressure, and do a blood test to assess your cholesterol level.
Before having the cholesterol test, you may be asked not to eat for 12 hours so there's no food in your body that could affect the result. Your doctor or a nurse can carry out the blood test. A sample will be taken either using a needle and a syringe or by pricking your finger.
Your doctor will also ask about your lifestyle, how much exercise you do and whether you smoke. All these factors will be considered as part of the diagnosis.
To confirm a suspected diagnosis, you may be referred for more tests. A number of different tests are used to diagnose heart-related problems, including:
- electrocardiogram (ECG)
- blood tests
- coronary angiography
- radionuclide tests
- magnetic resonance imaging (MRI) scans
- computerised tomography (CT) scans
An ECG records the rhythm and electrical activity of your heart. A number of electrodes (small, sticky patches) are put on your arms, legs and chest. The electrodes are connected to a machine that records the electrical signals of each heartbeat.
Although an ECG can detect problems with your heart rhythm, an abnormal reading doesn't always mean there's something wrong. Similarly, a normal reading doesn't always rule out heart problems.
In some cases, you may have an exercise ECG test, or 'stress test'. This is when an ECG recording is taken while you're exercising (usually on a treadmill or exercise bike). If you experience pain while exercising, the test can help identify whether your symptoms are caused by angina, which is usually due to CHD.
An X-ray may be used to look at the heart, lungs and chest wall. This can help rule out any other conditions that may be causing your symptoms.
An echocardiogram is similar to the ultrasound scan used in pregnancy. It produces an image of your heart using sound waves. The test can identify the structure, thickness and movement of each heart valve and can be used to create a detailed picture of the heart.
During an echocardiogram, you'll be asked to remove your top and a small handheld device called a transducer will be passed over your chest. Lubricating gel is put onto your skin to allow the transducer to move smoothly and make sure there is continuous contact between the sensor and the skin.
In addition to cholesterol testing, you may need to have a number of blood tests to monitor the activity of the heart. These may include cardiac enzyme tests, which can show whether there has been recent damage to the heart muscle.
Coronary angiography, also known as a cardiac catheter test, can identify whether the coronary arteries are narrowed and how severe any blockages are. It also provides information about the pressure inside your heart chambers and how well your heart is functioning.
In an angiogram, a catheter (flexible tube) is passed into an artery in your groin or arm and guided into the coronary arteries using X-rays. A dye is injected into the catheter to show up the arteries supplying your heart with blood. A number of X-ray pictures are taken, which will highlight any blockages. It's usually performed under local anaesthetic.
A coronary angiogram is relatively safe and serious complications are rare. The risk of having a heart attack, stroke or dying during the procedure is estimated at about 1 or 2 in every 1,000. However, after having a coronary angiogram you may experience some minor side effects, including:
- a slightly strange sensation when the dye is put down the catheter
- a small amount of bleeding when the catheter is removed
- a bruise in your groin or arm
Radionuclide tests can indicate how strongly your heart pumps and show the flow of blood to the muscular walls of your heart. Radionuclide tests provide more detailed information than the exercise ECG test.
During a radionuclide test, a small amount of a radioactive substance called an isotope is injected into your blood (sometimes during exercise). If you have difficulty exercising, you may be given some medication to make your heart beat faster. A camera placed close to your chest picks up the radiation transmitted by the isotope as it passes through your heart.
Magnetic resonance testing (MRI)
An MRI scan can be used to produce detailed pictures of your heart. During an MRI scan, you lie inside a tunnel-like scanner that has a magnet around the outside. The scanner uses a magnetic field and radio waves to produce images.
Computerised tomography (CT) scan
A CT scan uses X-rays and a computer to create detailed images of the inside of your body. During a CT scan, you lie on a bed while a small tube that takes X-rays moves and rotates around your body.
Coronary heart disease treatment
If you've been diagnosed with CHD, you can reduce your risk of further episodes by making simple lifestyle changes.
For example, stopping smoking after a heart attack will quickly reduce your risk of having a heart attack in the future to near that of a non-smoker.
Other lifestyle changes, such as eating more healthily and doing regular exercise, will also reduce your future risk of heart disease.
Read more about preventing CHD.
Many different medicines are used to treat CHD. Usually, they either aim to reduce blood pressure or widen your arteries. Some heart medicines have side effects, so it may take a while to find one that works for you. Your doctor or specialist will discuss the various options with you.
Antiplatelets are a type of medicine that can help reduce the risk of a heart attack by thinning your blood and preventing it from clotting. Common antiplatelet medicines include low-dose aspirin, clopidogrel, ticagrelor, and prasugrel.
If you have a high blood cholesterol level, cholesterol-lowering medicine called statins may be prescribed. Examples include simvastatin, pravastatin and atorvastatin. They work by blocking the formation of cholesterol and increasing the number of LDL receptors in the liver, which helps remove the LDL cholesterol from your blood. This helps slow the progression of CHD, and will make having a heart attack less likely. Not all statins are suitable for everyone, so you may need to try several different types until you find one that is suitable.
Beta-blockers – including acebutolol, atenolol, bisoprolol, metoprolol and propranolol – are often used to prevent angina and treat high blood pressure. They work by blocking the effects of a particular hormone in the body, which slows down your heartbeat and improves blood flow.
Nitrates are used to widen your blood vessels. Doctors sometimes refer to nitrates as "vasodilators". They're available in a variety of forms, including tablets, sprays, skin patches and ointments such as glyceryl trinitrate and isosorbide mononitrate.
Nitrates work by relaxing your blood vessels, letting more blood pass through them. This lowers your blood pressure and relieves any heart pain you have. Nitrates can have some mild side effects, including headaches, dizziness and flushed skin.
ACE (angiotensin-converting enzyme) inhibitors
ACE inhibitors are commonly used to treat high blood pressure. Examples include ramipril and lisinopril. They block the activity of a hormone called angiotensin II, which causes the blood vessels to narrow. As well as stopping the heart working so hard, ACE inhibitors improve the flow of blood around the body.
Your blood pressure will be monitored while you are taking ACE inhibitors, and regular blood tests will be needed to check that your kidneys are working properly. Around one in 10 people have kidney problems as a result of taking the drug.
If ACE inhibitors have been prescribed for you, do not stop taking them without first consulting your doctor. If you do, it is likely your symptoms will get worse quickly.
Side effects of ACE inhibitors can include a dry cough and dizziness.
Angiotensin II receptor antagonists
Angiotensin II receptor antagonists work in a similar way to ACE inhibitors. They are used to lower your blood pressure by blocking angiotensin II. Mild dizziness is usually the only side effect. Angiotensin II receptor antagonists are often prescribed as an alternative to ACE inhibitors, as they do not cause a dry cough.
Calcium channel blockers
Calcium channel blockers also work to decrease blood pressure by relaxing the muscles that make up the walls of your arteries. This causes the arteries to become wider, reducing your blood pressure. Examples include verapamil and diltiazem. Side effects include headaches and facial flushing, but these are mild and usually decrease over time.
Procedures and surgery
If your blood vessels are narrow due to a build-up of atheroma (fatty deposits), or if your symptoms cannot be controlled using medication, surgery may be needed to open up or replace blocked arteries. Some of the main procedures used to treat blocked arteries are outlined below.
Coronary angioplasty is also known as percutaneous coronary intervention (PCI), percutaneous transluminal coronary angioplasty (PTCA), or balloon angioplasty.
Angioplasty may be a planned procedure for some people with angina, or an urgent treatment if the symptoms have become unstable. Having a coronary angiogram will determine if you're suitable for treatment. Coronary angioplasty is also performed as an emergency treatment during a heart attack.
During angioplasty, a small balloon is inserted to push the fatty tissue in the narrowed artery outwards. This allows the blood to flow more easily. A metal stent (a short, wire mesh tube) is usually placed in the artery to hold it open. Drug-eluting stents can also be used. These release drugs to stop the artery from narrowing again.
Coronary artery bypass graft
Coronary artery bypass grafting (CABG) is also known as bypass surgery, heart bypass, or coronary artery bypass surgery.
It/s performed in patients where the arteries become narrowed or blocked. A coronary angiogram will determine if you're suitable for treatment. Off-pump coronary artery bypass (OPCAB) is a type of coronary artery bypass surgery performed without the need for a heart-lung machine, and keeps blood and oxygen circulating around the body.
A blood vessel is inserted (grafted) between the aorta (the main artery leaving the heart) and a part of the coronary artery beyond the narrowed or blocked area. This allows the blood to bypass (get around) the narrowed sections of coronary arteries.
In a small number of cases, when the heart is severely damaged and medicine is not effective, or when the heart becomes unable to adequately pump blood around the body (heart failure), a heart transplant may be needed. A heart transplant involves replacing a heart that is damaged or is not working properly with a healthy donor heart.
Preventing coronary heart disease
There are several ways you can help reduce your risk of developing coronary heart disease (CHD), such as lowering your blood pressure and cholesterol levels.
Eat a healthy, balanced diet
A low-fat, high-fibre diet is recommended, including plenty of fresh fruit and vegetables (5 portions a day) and whole grains. You should limit the amount of salt you eat to no more than 6g (0.2oz)(about one teaspoonful) a day as too much salt will increase your blood pressure.
There are 2 types of fat: saturated and unsaturated. You should avoid food containing saturated fats because these will increase your cholesterol levels.
Foods high in saturated fat include:
- meat pies
- sausages and fatty cuts of meat
- ghee, a type of butter often used in Indian cooking
- hard cheese
- cakes and biscuits
- foods that contain coconut or palm oil
However, a balanced diet should include a small amount of unsaturated fat, which will help reduce your cholesterol levels.
Foods high in unsaturated fat include:
- oily fish
- nuts and seeds
- sunflower, rapeseed, olive and vegetable oils
You should also try to avoid too much sugar in your diet as this can increase your chances of developing diabetes, which is proven to dramatically increase your chances of developing CHD.
Be more physically active
Combining a healthy diet with regular exercise is the best way of maintaining a healthy weight. Having a healthy weight reduces your chances of developing high blood pressure.
Regular exercise will make your heart and blood circulatory system more efficient, lower your cholesterol level, and also keep your blood pressure at a healthy level.
Keep to a healthy weight
Your doctor or practice nurse can tell you what your ideal weight is in relation to your build and height.
Give up smoking
If you smoke, giving up will reduce your risk of developing CHD. Smoking is a major risk factor for developing atherosclerosis (furring of the arteries). It also causes the majority of cases of coronary thrombosis in people under the age of 50.
Reduce your alcohol consumption
If you drink, stick to the recommended guidelines. The recommended daily amount of alcohol for men is 3 to 4 units a day and 2 to 3 units for women. Always avoid binge drinking.
Keep your blood pressure under control
You can keep your blood pressure under control by eating a healthy diet low in saturated fat, exercising regularly, and, if required, taking the appropriate medication to lower your blood pressure. Your target blood pressure should be below 140/85mmHg. If you have high blood pressure, ask your doctor to check your blood pressure regularly.
Keep your diabetes under control
If you have diabetes, you have a greater risk of developing CHD. Being physically active and controlling your weight and blood pressure will help manage your blood sugar level. Your target blood pressure level should be below 130/80mmHg.
Take any medication prescribed for you
If you have CHD, you may be prescribed medication to help relieve your symptoms and stop further problems from developing. If you don't have CHD but do have high cholesterol, high blood pressure or a history of family heart disease, your doctor may prescribe medication to prevent you from developing heart-related problems.
If you're prescribed medication, it's vital you take it and follow the correct dosage. Don't stop taking your medication without consulting your doctor first, as doing so is likely to make your symptoms worse and put your health at risk.
Recovery from coronary heart disease
After having heart surgery or problems like a heart attack, it's possible to resume a normal life.
Cardiac rehabilitation programme
If you have heart surgery, a member of the cardiac rehabilitation team may visit you in hospital to give you information about your condition and the procedure you're having. This care will usually continue after you've left hospital. For the first few weeks following your surgery, a member of the cardiac rehabilitation team may visit you at home or call you to check on your progress.
What happens in cardiac rehabilitation programmes can vary widely, but most will cover the following basic areas:
- relaxation and emotional support
Once you've completed your rehabilitation programme, it's important you continue to take regular exercise and lead a healthy lifestyle. This will help protect your heart and reduce the risk of further heart-related problems.
Self-care is an integral part of daily life, and is all about you taking responsibility for your own health and wellbeing with the support of those involved in your care. Self-care includes actions you take for yourself every day in order to stay fit and maintain good physical and mental health, prevent illness or accidents, and care more effectively for minor ailments and long-term conditions.
People living with long-term conditions can benefit enormously from being supported so they can self-care. They can live longer, have less pain, anxiety, depression and fatigue, have a better quality of life, and be more active and independent.
If you have or have had a heart condition, or if you're caring for someone with a heart condition, you might find it useful to meet other people in your area who are in a similar situation. Heart support groups organise regular exercise sessions, such as walking groups, as well as other social activities. Your doctor or specialist can provide you with details about your nearest group.
Relationships and sex
Coming to terms with a long-term condition such as heart disease can put a strain on you, your family and your friends. It can be difficult to talk with people about your condition, even if they're close to you. Be open about how you feel and let your family and friends know what they can do to help. But don't feel shy about telling them you need some time to yourself.
Your sex life
If you have coronary heart disease (CHD) or you've recently had heart surgery, you may be concerned about having sex. Usually, as soon as you feel well enough you can resume sexual activity. Communicate with your partner and stay open-minded. Explore what you both like sexually. Simply touching, being touched and being close to someone helps a person feel loved and special.
Returning to work
After recovering from heart surgery, you should be able to return to work, but it may be necessary to change the type of work you do. For example, you may not be able to do a job that involves heavy physical exertion. Your specialist will be able to advise you about when you can return to work and what type of activities you should avoid.