Cardiovascular system
Published: 27th February, 2013 in: Heart Disease
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 over 300,000 heart attacks in the UK each year.
Causes
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 during 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 after a cut. 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.
A person is particularly likely to develop coronary heart disease if there is a history of heart disease in the family, there is a high level of cholesterol in the blood, if the person smokes, does not take regular exercise, is overweight, has diabetes or high blood pressure.
Symptoms
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 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, for example walking or running, or by an 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. The area of the heart normally supplied by the blood vessel becomes starved of oxygen and, if the clot is not removed, that part of the heart becomes permanently damaged. Symptoms of a heart attack can range from a severe pain in the centre of the chest to a 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. Someone who is having a heart attack may 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.
Treatment
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 cholesterol levels are high, drugs such as statins or fibrates, may be used to block the production of cholesterol in the body, or ezetimibe that blocks the absorption of cholesterol from the diet may be used to lower 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 aspirin causing stomach bleeding may outweigh its benefits on the heart and circulation.
Drugs called ACE inhibitors or A2 blockers (angiotensin 2 antagonists) 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.
When to see your pharmacist
Tests for diabetes and cholesterol levels and blood pressure measurements are now carried out 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 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 with over the counter medicines.
When to see your doctor
Your doctor may be able to tell if you have angina from the symptoms you describe. Your 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, weight and smoking history. If these factors are present, your doctor may prescribe a range of products to treat these risk factors while also treating your angina or heart attack, to reduce the chances of your angina getting worse, your having another heart attack and to prevent heart failure.
Living with heart disease
Improvement in life style can dramatically reduce your chances of getting coronary heart disease, of your angina getting worse, or your having another heart attack.
If you smoke, you should make every effort to stop the habit. Stopping smoking is the single most significant factor in reducing the risk of coronary heart disease. From the moment you stop smoking, the risk of heart attack starts to reduce. There are many products for nicotine replacement therapy, such as patches, chewing gums, lozenges and nasal sprays, available to purchase over the counter or on prescription that can help reduce the craving to smoke while giving up. Alternatively, there are medicines such as bupropion and varenicline tablets that are available on prescription that help reduce craving and the dependency on nicotine. Whichever products are used, they will only help if you are committed to stop smoking and you will be more likely to succeed if you also receive counselling and support while trying to give up. Do not be afraid to ask your doctor, practice nurse or pharmacist for help.
If you are offered a cigarette, be positive, tell your family and friends that you have stopped smoking, not that you are trying to give up. Try to occupy your hands and your thoughts in situations when you used to smoke, for example after a meal or with a drink, to break the association of smoking with these social occasions. If you do lapse and smoke a cigarette, do not regard this as having failed to give up. Instead, regard it has a temporary set-back and use it to strengthen your resolve not to have another.
Control your weight. By keeping close to the recommended weight for your height, you can help keep your blood pressure down and reduce the amount of work your heart has to do.
Eat healthily. Three meals - breakfast, lunch and dinner - spread evenly throughout the day is best. Do not skip breakfast as it increases the tendency to snack. Limit the size of your meal portions and do not eat large meals late at night. Choose foods with a low glycaemic index (GI) such as lentils or porridge that are slowly digested and absorbed, so helping keep hunger pangs at bay.
Eat a variety of fruit and vegetables. Aim for at least five portions a day. It may sound a lot, but can easily be achieved if you eat an apple, banana or raw carrot as a snack instead of a bag of crisps or biscuits. A diet that is low in fat, particularly saturated fat, can help lower your blood cholesterol level. So cut down on animal fat and eat more oily fish such as herring and mackerel. Salt can contribute to high blood pressure so it is best to limit your intake to no more than 6 grams a day. Get into the habit of reading the labels on food products and choose those with a low salt and low fat content. Stop adding salt to vegetables when cooking and do not automatically sprinkle salt over your food before tasting. You’ll not be able to notice the difference after a very short time.
Reduce your alcohol consumption. Heavy alcohol drinking can contribute to high blood pressure, strokes and can damage the heart muscle. Men should not drink more than 4 units of alcohol in any one day, or more than 21 units of alcohol per week. Women should not drink more than 3 units of alcohol in any one day, or more than 14 units of alcohol per week. As a guide, a pint of beer is about 2 units and a small glass of wine is about one and a half units.
Exercise regularly. Physical activity halves the risk of developing heart disease. If you’ve got angina or had a heart attack it is a good idea to speak to your doctor before starting an exercise programme. Take it easy at first and build up your level of fitness gradually. Aim for at least 30 minutes of moderate activity five days a week.
Advice for carers and other family members
Support the person you care for or the person you live with who has heart disease. Change your eating habits as a family. If you eat healthily, shopping, cooking and meal times will be easier and there will be less temptation to everyone to eat the wrong things. As heart disease tends to run in families, you will also be reducing your family’s risk of angina and heart attacks in the future.
All members of the family should be discouraged from smoking as this helps reducing cravings in the person who has stopped smoking and stops passive smoking which also poses a risk of heart disease.
Useful Tips
- Eat healthily (see healthier eating section)
- Be more active
- Be smoke free (see give up smoking section)
- Control your weight
- Reduce alcohol
Further information
For further information on heart disease contact the British Heart Foundation, a registered charity whose mission is to play a leading role in the fight against disease of the heart and circulation through pioneering research, vital prevention activity and ensuring quality care and support for everyone living with heart disease.