Also called coronary heart disease or ischaemic heart disease, coronary artery disease is caused by a build-up of fatty substances that slows or completely blocks the blood supply to the heart.
Your heart is a muscle about the size of your fist. It beats around 70 times a minute, pumping blood around your body. The process of circulation takes the blood from the right side of your heart to the lungs where it is oxygenated. This oxygenated blood then returns to the heart and is pumped, via your arteries, to the rest of your body. The blood returns to your heart via the veins, where the process begins again.
Coronary arteries feed the heart with its own blood supply. Atherosclerosis is the process by which these arteries become furred up with fatty deposits, reducing or totally blocking this vital blood supply.
The primary symptoms of coronary artery disease are:
- Angina – this is chest pain caused by reduced blood flow to your heart muscle. It can range from mild discomfort, similar to indigestion, to feeling a dull, heavy or tight pain in the centre of your chest which can spread to your left arm, jaw, neck or back. It can come on suddenly after physical exertion or stress but normally stops after a few minutes’ rest or using a nitrate spray. Sometimes you can also feel sick or breathless. Angina may a warning sign that you are risk of having a heart attack or stroke.
- Breathlessness when you exert yourself over and above normal levels.
- Heart attack – If the arteries become completely blocked it can cause a heart attack resulting in permanent damage to the heart muscle and sometimes death Unlike with angina, the pain you experience will not be relieved by using a nitrate spray. You might also experience symptoms such as:
- Pain in other parts of the body particularly your arms, jaw, neck and back.
- Nausea and sweating.
- Sometimes there are no symptoms at all with a heart attack, particularly if you are elderly or have diabetes.
- Heart failure – This occurs when the heart can’t pump blood around the body properly, normally because it has become too weak or stiff. This can cause a build up of fluid in the lungs, making it difficult to breathe.
Arrhythmia is a problem with the heart rhythm. Your heartbeat is controlled by electrical impulses. If these malfunction the heart can begin to beat in an abnormal way; too quickly, too slowly or with an irregular rhythm.
More than two million people in the UK are believed to have some kind of arrhythmia. Most are able to lead a normal life, providing they have a proper diagnosis. However, atrial fibrillation makes you five times more likely to have a stroke. And. certain types of arrhythmia in people with severe heart conditions can lead sudden cardiac death.
For this reason, if you have any of the symptoms associated with possible arrhythmia you should see your doctor to have a proper diagnosis. If it is confirmed that you have arrhythmia, there are many different treatments available.
Known as atherosclerosis, fatty deposits can collect in your arteries over a period of time as a result of lifestyle choices and other health conditions. Your risk of developing atherosclerosis is increased if you:
- Have a high cholesterol level.
- Smoke – If you smoke, you increase your risk of developing heart disease by 24%. Smoking puts a strain on your heart by making it work faster and increasing the risk of blood clots. Chemicals in cigarette smoke can damage the lining of your arteries.
- Have high blood pressure.
- Don’t exercise regularly.
- Have diabetes – people with this condition have double the risk of coronary artery disease. Diabetes causes the lining of blood vessels to thicken, thereby restricting blood flow.
- Have a thrombosis – this is a blood clot in a vein or artery. A thrombosis in the coronary artery will normally trigger a heart attack.
- Are overweight.
- Have a family history of coronary artery disease.
Coronary artery disease can be life-threatening; therefore it is important to get a prompt and accurate diagnosis if you believe you may be at risk. This may include:
- A blood test to determine your cholesterol levels. You may need to avoid eating anything for 12 hours beforehand.
- A medical/family history to assess your predisposition to the condition. Your GP will ask about your lifestyle, including whether you smoke, drink alcohol or exercise.
- Exercise stress test, also called a treadmill test – this is used to assess how well the heart performs under stress. You will be asked to walk on a treadmill or pedal an exercise bike. The speed and incline will gradually be increased. You will be monitored during the test using an ECG to see what your heart rate and blood pressure are doing. The tests normally last no longer than 12 minutes.
- Nuclear medicine/radionuclide scan – Cardiac nuclear medicine uses small doses of a radioactive chemical called radiotracers to evaluate the heart for coronary artery disease. Radiotracers are injected into the bloodstream. As they travel through the heart, they give off gamma rays which are picked up by a special camera and used to create an image of the inside of your body. Cardiac nuclear medicine provides a detailed picture of the blood flow to your heart muscle and can show how well your heart is functioning. Nuclear medicine can also be combined with CT scans or MRI scans. It can be used to provide an accurate diagnosis for unexplained chest pain, breathlessness and an abnormal electrocardiogram. However, it is not suitable for everyone, particularly pregnant or breastfeeding women.
- Cardiac CT scan – this uses X-rays to build up a detailed picture of your heart and its blood vessels. A CT angiograph looks at the arteries that supply blood to your heart to identify blockages or narrowing. A coronary calcium scan assesses if there is a build-up of calcium in your arteries.
- MRI scan – a cardiac MRI scan uses a magnetic field to produce detailed pictures of the structures within the heart. It can evaluate how well it is functioning.
- Invasive coronary angiography – this procedure, also called cardiac catheterisation, involves taking X-rays of the heart’s arteries to diagnose conditions such as angina. It is regarded as the best way to diagnose coronary artery disease. It may also be used to plan a coronary angioplasty, which is a surgical procedure to widen narrowed or blocked blood vessels. The procedure, which is carried out under local anaesthetic, entails inserting a long, flexible tube called a catheter into a blood vessel and feeding this up to the heart and coronary arteries. Dye is injected into the catheter and X-rays are taken. They clearly highlight any narrowed or blocked areas.
Coronary artery disease cannot be cured, however there are treatments that can help to manage the symptoms and reduce the risk of further problems.
Among the treatments that may be recommended are:
- Lifestyle changes – including stopping smoking, eating a healthy balanced diet and exercising regularly.
- Medication – many different types of medication are available to manage the symptoms of coronary artery disease. For example:
- Antiplatelets reduce the risk of a heart attack by thinning your blood to prevent it from clotting. Low-dose aspirin is a type of antiplatelet.
- Statins help to lower cholesterol and increase the number of low-density lipoprotein receptors in your liver. These help to remove LDL cholesterol from your blood and reduce the risk of heart attacks.
- Beta-blockers are used to prevent angina and treat high blood pressure.
- Nitrates are used to widen your blood vessels. They come in tablet form as well as sprays and skin patches.
- ACE inhibitors and angiotensin II receptor antagonists are used to treat high blood pressure. They block a hormone called angiotensin II, which causes blood vessels to narrow.
- Calcium channel blockers relax the muscles in the arteries to decrease blood pressure.
- Diuretics reduce fluid retention by flushing excess water from your body.
- Surgery – If the symptoms cannot be controlled using medication, surgical procedures may be used to open up blocked arteries or to bypass them. These include:
- Coronary angioplasty – a small balloon is inserted into the artery to push the fatty tissue outwards and allow the blood to flow more easily. A metal stent is placed in the artery to hold it open. Some stents release drugs to prevent the artery from narrowing again.
- Coronary artery bypass graft – also known as a heart bypass, this involves inserting a blood vessel between the aorta (the main artery leaving the heart) and a part of the coronary artery beyond the area that is narrowed or blocked. In this way, blood can bypass the damaged section.
- Heart transplant – if your heart is severely damaged and medicine is not effective, it may be replaced with a healthy donor heart using transplant surgery. This only happens in a small number of cases.