Cardiovascular system

Heart disease, also know as coronary heart disease, is the single most common cause of death in the UK. It is the term used to describe the gradual narrowing of the coronary arteries which can lead to angina or a heart attack. Over 2 million people in the UK have angina and there are approximately 270,000 heart attacks in the UK each year.

The coronary arteries are the blood vessels that supply the heart muscle with blood and oxygen. Coronary artery disease occurs when these blood vessels become narrowed by a gradual build-up of fatty material within their walls. This process is called ‘atherosclerosis’ and the fatty material is called ‘atheroma’. In time, the artery may become so narrow that it cannot deliver enough oxygen-containing blood to the heart muscle when its demands are high – for example when you are doing exercise. The pain or discomfort that happens as a result is called angina. The pain is caused by the heart muscle becoming short of oxygen, a condition called ischaemia.

Narrowing of the coronary arteries also increases the chances of a blood clot or a thrombosis forming. Blood is prevented from flowing smoothly through the narrowed arteries and when it comes into contact with the narrowed, damaged artery wall it forms a clot, similar to the way that blood clots when you cut yourself. The clot or thrombosis further restricts the flow of blood. If the coronary arteries become completely blocked, no blood can get through to supply the heart muscle, the area of the heart becomes starved of oxygen leading to a heart attack or, what doctors call, a myocardial infarction.

You are particularly likely to develop coronary heart disease if you have a history of heart disease in the family, you have high cholesterol levels in your blood, you smoke, you do not take regular exercise, you are overweight, if you have diabetes or high blood pressure.

Angina is an uncomfortable feeling or pain in the chest. It usually feels like a heaviness or tightness in the centre of the chest which may spread to the arms, neck, jaw, back or stomach. In some people, the pain or tightness may affect only the arm, neck, stomach or jaw. Some people describe angina as a dull, persistent ache. For some people the tightness is severe, for others it is not much more than mild discomfort, such as a dull, persistent ache. Angina can be brought on by physical activity, such as walking, or emotional upset. If left untreated, permanent damage may be caused to the heart resulting in heart failure and an inability of the heart to pump blood properly.

A heart attack happens when one of the coronary arteries becomes blocked – for example by a blood clot – part of your heart may be starved of oxygen and may become permanently damaged. Symptoms of a heart attack can range from a severe pain in the centre of the chest to having mild chest discomfort or generally feeling unwell. In some cases people have mistaken the pain for indigestion. The pain often feels like a heaviness or tightness which may also spread to the arms, neck, jaw, back or stomach. It may affect only the neck, jaw, arms or stomach. Someone who is having a heart attack may also sweat, feel light-headed, feel sick, or be short of breath. A heart attack may also cause the rhythm of the heart to be disturbed. If severe or if left untreated, a heart attack can be fatal.

Medicines

Improvement in life style can dramatically reduce your chances of getting coronary heart disease. Stopping smoking is the most significant factor in reducing the risk of coronary heart disease. Improving diet by cutting down on animal fats, eating 5 portions of fruit and vegetables each day and more fish also has a significant effect, as does taking regular, brisk exercise and reducing your alcohol consumption.

If you do develop coronary artery disease there are a number of treatments that can help reduce symptoms and reduce the risk of your having a heart attack.

Nitrates are the drugs of choice for relieving a sudden attack of angina. Taken as a spray or as a tablet dissolved under the tongue, nitrates help widen the coronary arteries and restore the oxygen supply to the heart. Nitrates, along with other drugs such as beta-blockers and calcium antagonists can also be used to help prevent angina. These drugs act through a variety of mechanisms including widening the coronary arteries, to improve blood supply to the heart, and by slowing the contractions of the heart to reduce the heart’s demand for oxygen.

If your cholesterol levels are high, drugs such as statins or fibrates, that block the production of cholesterol in the body, or ezetimibe that blocks the absorption of cholesterol from the diet may be used to lower your cholesterol levels. (See separate section on cholesterol)

Low dose aspirin may also be used to reduce the risk of heart attacks. Although aspirin is best known as a simple pain killer, taken in low doses aspirin helps stop blood from clotting and therefore reduces the chances of a thrombosis developing in coronary heart disease. However, people who do not have symptomatic or diagnosed artery or heart disease should not take a daily dose of aspirin in the hope that it will prevent heart trouble because the risks of aspiron causing stomach bleeding may outweigh its benefits on the heart and circulation.

Drugs called ACE inhibitors may also be used to reduce the risk of heart attacks, or will be used after a previous heart attack, to reduce the chances of further heart attacks occurring and prevent heart failure from developing.

If drug treatment fails to work, surgical techniques known as coronary angioplasty or coronary artery bypass surgery will be used to widen or replace the coronary arteries and so restore a normal blood supply to the heart.

Tests for diabetes and cholesterol levels and blood pressure measurements are now done in many pharmacies. These provide a convenient way to check on some of the major risk factors involved in heart disease. If the tests show that you are at risk, your pharmacist will advise you to see your doctor.

Your pharmacist can also help you with many of the changes in life-style that can have a significant effect in reducing your risk of heart disease. Advice on diet, exercise and giving up smoking is freely available and, if you do smoke, your pharmacist can supply a range of nicotine replacement products that will help you stop.

If you do suffer from angina or have had a heart attack it is likely that you will need to take quite a large number of drugs prescribed by your doctor. In such circumstances, it is advisable to register with your local pharmacy for the ‘Repeat Dispensing Service’. In this way, your pharmacist will get to know you and which medicines you are taking and will be in a better position to answer any question that you have about your treatment. If you are buying any over the counter medicines to treat other more minor illnesses, let your pharmacist know which medicines you are taking as their effects could be changed if they react together.

Your doctor may be able to tell if you have angina from the symptoms you describe. The doctor will listen to your heart to check its rate and rhythm, and will assess your general condition, take your blood pressure and check for diabetes. Your blood will be tested to measure the level of cholesterol and your heart will be monitored with an ECG (electrocardiogram) to confirm the diagnosis of angina. Your doctor may decide to send you to hospital for further tests such as an angiogram which determines the extent of narrowing of the coronary arteries.

If angina or a heart attack is diagnosed your doctor will also take into account other factors such as diabetes, high blood pressure, overweight and smoking. If these factors are present, your doctor will prescribe a range of products to treat these risk factors as well as to manage your angina and heart attack, to reduce the chances of your angina getting worse, or your having another heart attack and to prevent heart failure.

For further information on heart disease contact the British Heart Foundation. You can order free booklets from the British Heart Foundation by calling 0870 600 6566 or visit
bhf.org.uk