A heart attack is a serious medical emergency in which the supply of blood to the heart is suddenly blocked, usually by a blood clot. Lack of blood to the heart can seriously damage the heart muscle.
A heart attack is known medically as a myocardial infarction or MI.
Symptoms can include:
chest pain – the chest can feel like it is being pressed or squeezed by a heavy object, and pain can radiate from the chest to the jaw, neck, arms and back
shortness of breath
feeling weak and/or lightheaded
overwhelming feeling of anxiety
It is important to stress that not everyone experiences severe chest pain; the pain can often be mild and mistaken for indigestion.
It is the combination of symptoms that is important in determining whether a person is having a heart attack, and not the severity of chest pain.
Treating heart attacks
A heart attack is a medical emergency. Dial 999 and ask for an ambulance if you think you or someone you know is having a heart attack.
If the casualty is not allergic to aspirin and it’s easily available, give them a tablet (ideally 300mg) to slowly chew and then swallow while waiting for the ambulance to arrive.
The aspirin will help to thin the blood and reduce the risk of a heart attack.
Treatment for a heart attack will depend on how serious it is. Two main treatments are:
using medication to dissolve blood clots
surgery to help restore blood to the heart
What causes a heart attack?
Coronary heart disease (CHD) is the leading cause of heart attacks. CHD is a condition in which coronary arteries (the major blood vessels that supply blood to the heart) get clogged up with deposits of cholesterol. These deposits are called plaques.
Before a heart attack, one of the plaques ruptures (bursts), causing a blood clot to develop at the site of the rupture. The clot may then block the supply of blood running through the coronary artery, triggering a heart attack.
Your risk of developing CHD is increased by:
a high-fat diet
high blood pressure
being overweight or obese.
The time it takes to recover from a heart attack will depend on the amount of damage to the heart muscle. Some people are well enough to return to work after two weeks. Other people may take several months to recover. The recovery process aims to:
reduce your risk of another heart attack through a combination of lifestyle changes, such as eating a healthy diet, and medications, such as statins (which help lower blood cholesterol levels)
gradually restore your physical fitness so you can resume normal activities (known as cardiac rehabilitation)
Most people can return to work after having a heart attack, but how quickly will depend on your health, the state of your heart and the type of work you do..
Who is affected
Heart attacks are one of the most common reasons why a person requires emergency medical treatment.
Men are more likely to have a heart attack than women. The British Heart Foundation estimates that around 50,000 men and 32,000 women have a heart attack each year in England.
Most heart attacks occur in people aged over 45.
Complications of heart attacks can be serious and possibly life-threatening. These include:
arrhythmia – this is an abnormal heartbeat, where the heart begins beating faster and faster, then stops beating (cardiac arrest)
cardiogenic shock – where the heart's muscles are severely damaged and can no longer contract properly to supply enough blood to maintain many body functions
heart rupture – where the heart’s muscles, walls or valves split apart (rupture)
These complications can occur quickly after a heart attack and are a leading cause of death.
Many people will die suddenly from a complication of a heart attack before reaching hospital.
The outlook for people who have had a heart attack can be highly variable, depending on:
their age – the older you are, the more likely you are to experience serious complications
the severity of the heart attack – specifically, how much of the heart's muscle has been damaged during the attack
how long it took before a person received treatment – the longer the delay, the worse the outlook tends to be
In general, around one third of people who have a heart attack die as a result. These deaths often occur before a person reaches hospital or, alternatively, within the first 28 days after the heart attack.
If a person survives for 28 days after having a heart attack, their outlook improves dramatically and most people will go on to live for many years.
Symptoms of a heart attack
Dial 999 immediately if you suspect that you or someone you know is having a heart attack.
Symptoms can include:
chest pain – a sensation of pressure, tightness or squeezing in the centre of your chest
pain in other parts of the body – it can feel as if the pain is travelling from your chest to your arms (usually the left arm is affected, but it can affect both arms), jaw, neck, back and abdomen
feeling lightheaded or dizzy
shortness of breath
feeling sick (nausea) or being sick (vomiting)
an overwhelming sense of anxiety (similar to having a panic attack)
coughing or wheezing
Although the chest pain is often severe, some people may only experience minor pain, similar to indigestion. In some cases, there may not be any chest pain at all, especially in women, the elderly and people with diabetes.
When to call an ambulance
It's the overall pattern of symptoms that helps to determine whether you are having a heart attack.
Do not worry if you have doubts. Assume that you are having a heart attack and dial 999 to ask for an ambulance immediately.
Paramedics would rather be called out to find an honest mistake has been made than be too late to save a person’s life.
Waiting for the ambulance
It is important to rest while you wait for an ambulance, to avoid unnecessary strain on your heart.
If aspirin is easily available and you know you are not allergic to it, slowly chew and then swallow an adult-sized tablet (300mg) while you are waiting for the ambulance to arrive.
The aspirin will help to thin your blood and restore blood supply to your heart.
In some cases a complication called ventricular arrhythmia can cause the heart to go into spasm and then to stop beating. This is known as sudden cardiac arrest.
Signs and symptoms suggesting a person has gone into cardiac arrest include:
they appear not to be breathing
they are not moving
they do not respond to any stimulation, such as being touched or spoken to
If you think somebody has gone into cardiac arrest and you do not have access to a piece of equipment called an automated external defibrillator (AED), you should perform chest compressions, as this can help restart the heart.
To carry out a chest compression:
Place the heel of your hand on the breastbone at the centre of the person’s chest. Place your other hand on top of your first hand and interlock your fingers.
Using your body weight (not just your arms), press straight down by 5-6cm on their chest.
Repeat this until an ambulance arrives.
Aim to do the chest compressions at a rate of 100-120 compressions a minute.
The above advice only applies to adults. For information about how to perform CPR in children, see how to resuscitate a child.
Automated external defibrillator (AED)
If you have access to a device called an AED, you should use it. An AED is a safe, portable electrical device that most large organisations keep as part of their first aid equipment.
It helps to establish a regular heartbeat during a cardiac arrest by monitoring the person's heartbeat and giving them an electric shock if necessary.
Causes of a heart attack
Heart attacks are caused by the blood supply to the heart being suddenly interrupted.
Like all other tissues and organs in the body, the heart needs a constant supply of oxygen-rich blood. Without this supply, heart muscles may be damaged and begin to die.
If this is not treated, heart muscles will experience irreversible damage. If a large portion of the heart is damaged in this way, the heart will stop beating (known as a cardiac arrest), resulting in death.
Coronary heart disease (CHD)
Coronary heart disease (CHD) is the leading cause of heart attacks. CHD is a condition in which the coronary arteries (the major blood vessels that supply the heart with blood) get clogged up with deposits of cholesterol. These deposits are called plaques.
During a heart attack, one of the plaques ruptures (bursts), causing a blood clot to develop at the site of the rupture. The clot may then block the blood supply running through the coronary arteries to the heart, triggering a heart attack.
Who's at risk
Risk factors for CHD, many of which are related to each other, are outlined below.
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%.
If you eat a diet high in saturated fat, your blood cholesterol levels will rise. This leads to an increase in your risk of CHD and heart attacks.
High blood pressure
Having poorly controlled high blood pressure (hypertension) can weaken the coronary arteries, making them more vulnerable to CHD. The higher your blood pressure, the greater your risk of CHD and heart attacks.
The increased levels of blood glucose associated with type 1 diabetesand type 2 diabetes can damage the coronary arteries, making them more vulnerable to CHD.
It is estimated that people with diabetes are two to five times more likely to develop CHD than the general population.
Being overweight or obese
Being overweight or obese does not directly increase your risk of CHD and heart attacks, but leads to related risk factors that do. In particular, people who are overweight or obese:
have an increased risk of developing high blood pressure
tend to have higher levels of cholesterol as a result of eating a high-fat diet
have an increased risk of developing type 2 diabetes
Lack of exercise
Lack of exercise is not directly related to an increased risk of CHD and heart attacks. However, it is linked to an increased risk of being overweight or obese and having high blood pressure.
Excessive alcohol consumption can cause high blood pressure and increased blood cholesterol levels, thereby increasing the risk of developing CHD.
Age and sex
The older you get, the more likely you are to develop some degree of CHD.
Men are two to three times more likely to have a heart attack than women.
A number of theories have been suggested to explain this increased risk, such as:
higher rates of excessive alcohol consumption in men
more men are overweight than women (although obesity levels are roughly the same for both sexes)
men may be less effective at coping with stress than women, and increased stress levels may affect their physical wellbeing
women may be protected by hormones before the menopause
If you have a first-degree relative (a parent, brother or sister) with a history of heart disease – such as angina, heart attack or stroke – you are twice as likely to develop similar problems, compared to the general population.
Rates of high blood pressure and diabetes are higher in people of African and African-Caribbean descent, which means that they also have an increased risk of CHD and heart attacks.
People of South Asian descent (those of Sri Lankan, Indian, Bangladeshi and Pakistani origin) are five times more likely to develop diabetes than the general population. Again, this increases their risk of CHD and heart attacks.
Research has found that exposure to air pollution – specifically traffic pollution – can cause a significant rise in your chance of developing CHD and, in turn, heart attacks.
Research carried out in 2011 estimated that air pollution could play a part in as many as 1 in 13 cases of heart attacks.
Less common causes
Some less common causes are described below.
An electrocardiogram (ECG) is an important test in suspected heart attacks. It should be carried out within 10 minutes of being admitted to hospital.
An ECG measures the electrical activity of your heart. Every time your heart beats, it produces tiny electrical signals. An ECG machine records these signals onto paper, allowing your doctor to see how well your heart is functioning.
An ECG is painless and takes about five minutes to perform. During the test, electrodes (flat metal discs) are attached to your arms, legs and chest. Wires from the electrodes are connected to the ECG machine, which records the electrical impulses.
An ECG is so important because:
it helps confirm the diagnosis of a heart attack
it helps determine what type of heart attack you have had, which will help determine the most effective treatment
Types of heart attack
Heart attacks can be classified by a measurement known as the ST segment. The ST segment is an electrical measurement recorded by an ECG. It corresponds to the level of damage inflicted on the heart.
The higher the ST segment, the greater the likely damage.
A number of other tests can be used to assess the state of your heart and check for related complications. However, because heart attacks are medical emergencies, some tests are usually only carried out once your initial treatment has begun and your condition has been stabilised.
Damage to your heart from a heart attack causes certain proteins to slowly leak into your blood. Enzymes are special proteins that help regulate chemical reactions that take place in your body.
If you have had a suspected heart attack, a sample of your blood will be taken so it can be tested for these heart proteins (known as cardiac markers). Your protein levels will be measured through a series of blood samples taken over the course of a few days.
This will allow damage to your heart to be assessed, and also help determine how well you are responding to treatment.
A chest X-ray can be useful if diagnosis of a heart attack is uncertain and there are other possible causes of your symptoms, such as a pocket of air trapped between the layers of your lungs (pneumothorax).
A chest X-ray can also be used to check whether complications have arisen from the heart attack, such as a build-up of fluid inside your lungs (pulmonary oedema).
An echocardiogram is a type of ultrasound scan that uses sound waves to build up a picture of the inside of your heart.
This can be useful to identify exactly which areas of the heart have been damaged and how this damage has affected your heart’s function.
Coronary angiography can help determine whether a blockage or narrowing has occurred in the coronary arteries and, if so, to locate the exact location of the blockage or narrowing.
The test involves inserting a thin tube, known as a catheter, into one of the blood vessels in your groin or arm. The catheter is guided into your coronary arteries using X-rays.
A special fluid, known as a contrast agent, is pumped through the catheter. This fluid shows up on X-rays, and studying how it flows around and through your heart can help locate the site of any blockage or narrowing.
Treating a heart attack
The treatment options for a heart attack depend on whether you have had an ST segment elevation myocardial infarction (STEMI), or another type of heart attack.
A STEMI is the most serious form of heart attack and requires emergency assessment and treatment. It is important that you are treated quickly to minimise damage to your heart.
If you have symptoms of a heart attack and an electrocardiogram (ECG) shows you have a STEMI, you will be assessed for treatment to unblock the coronary arteries.
The treatment used will depend on when your symptoms started and how soon you can access treatment.
If your symptoms started within the past 12 hours – you will usually be offered primary percutaneous coronary intervention (PCI).
If your symptoms started within the past 12 hours but you cannot access PCI quickly – you will be offered medication to break down blood clots.
If your symptoms started more than 12 hours ago – you may be offered a different procedure, especially if symptoms have improved. The best course of treatment will be decided after an angiogram and may include medication, PCI or bypass surgery.
Primary percutaneous coronary intervention (PCI)
PCI is the term for emergency treatment of STEMI, using surgery to widen the coronary artery (coronary angioplasty).
Coronary angiography is usually offered first to assess your suitability for PCI.
You may also be given blood-thinning medication such as aspirin,heparin, ticagrelor or bivalirudin to prevent further clots from developing. Some of these medications may be continued for several months after PCI.
A coronary angioplasty is a very complex type of surgery that requires specialist staff and equipment, and not all hospitals have the facilities needed to perform the surgery. This means you will need to be taken urgently, by ambulance, to one of the specialist centres (Heart Attack Centres) that now serve most of the UK's regions.
During coronary angioplasty, a tiny tube known as a catheter, with a sausage-shaped balloon at the end, is put into a large artery in your groin or arm. The catheter is passed through your blood vessels and up to your heart, over a fine guidewire, using X-rays to guide it, before being moved into the narrowed section of your coronary artery.
Once in position, the balloon is inflated inside the narrowed part of the artery to open it wide. A stent (flexible metal mesh) is usually inserted into the artery to help keep it open afterwards.
Medication to break down blood clots
Medications used to break down blood clots, known as thrombolytics or fibrinolytics, are usually given by injection.
Thrombolytics, or fibrinolytics, target and destroy a substance called fibrin. Fibrin is a tough protein that makes up blood clots by acting like a sort of fibre mesh that hardens around the blood.
Some examples of these types of medications include:
You may also be given an additional medication called a glycoprotein IIb/IIIa inhibitor if it is thought you have an increased risk of experiencing another heart attack at some point in the near future.
Glycoprotein IIb/IIIa inhibitors do not break up blood clots, but they prevent blood clots from getting bigger. They are, therefore, an effective method of stopping your symptoms getting worse.
Coronary artery bypass graft
A coronary angioplasty may not be technically possible sometimes if the anatomy of your arteries is different from normal. This may be the case if there are too many narrow sections in your arteries or if there are lots of branches coming off your arteries that are also blocked.
In such circumstances, an alternative surgical procedure, known as a coronary artery bypass graft (CABG), may be considered. A CABG involves taking a blood vessel from another part of your body, usually your chest or leg, to use as a graft.
The graft bypasses any hardened or narrowed arteries in the heart. A surgeon will attach the new blood vessel to the aorta and the other to the coronary artery above and below the narrowed area or blockage.
Non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina
If the results of your ECG show you have a "less serious" type of heart attack (known as a non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina), then blood-thinning medication, including aspirin and other medications, is usually recommended.
In some cases, further treatment with coronary angioplasty or coronary artery bypass graft may be recommended in cases of NSTEMI or unstable angina, after initial treatment with these medications.
Morphine is a painkiller usually given to relieve symptoms of chest pains and feelings of stress and anxiety.
Complications of a heart attack
Potential complications from a heart attack can vary widely, from mild to life threatening.
Some people experience what is sometimes referred to as a "minor" heart attack (although it is still very serious) with no associated complications. This is also known as an uncomplicated heart attack.
Other people experience a major heart attack, which has a wide range of complications and may require extensive treatment.
Some common complications of a heart attack are discussed in more detail below.
An arrhythmia is an abnormal heartbeat – this includes beating too quickly (tachycardia), too slowly (bradycardia) or irregularly (atrial fibrillation).
Arrhythmias can develop after a heart attack as a result of damage to the muscles. Damaged muscles disrupt electrical signals used by the body to control the heart. Some arrhythmias, such as tachycardia, are mild and cause symptoms such as:
palpitations (the sensation of your heart racing in your chest or throat)
Other arrhythmias can be life threatening, such as:
complete heart block, where electrical signals are unable to travel from one side of your heart to the other, so your heart cannot pump blood properly
ventricular arrhythmia, where the heart begins beating faster before going into a spasm and stops pumping altogether; this is
These life-threatening arrhythmias can be a major cause of death during the 24 hours after a heart attack.
However, survival rates have improved significantly since the invention of the portable defibrillator – an external device that delivers an electric shock to the heart and "resets" it to the right rhythm.
Mild arrhythmias can usually be controlled with medication such asbeta-blockers.
More troublesome arrhythmias that cause repeated and prolonged symptoms may need to be treated with a pacemaker. This is an electric device surgically implanted in the chest, which is used to help regulate the heartbeat.
Heart failure happens when your heart is unable to effectively pump blood around your body. It can develop after a heart attack if muscles in your heart are extensively damaged. This usually occurs in the left side of the heart (the left ventricle).
Symptoms of heart failure include:
shortness of breath
swelling in your arms and legs due to a build-up of fluid
Heart failure can be treated with a combination of medications and, in some cases, surgery.
Cardiogenic shock is similar to heart failure, but more serious. It develops when the heart’s muscles have been damaged so extensively it can no longer supply enough blood to maintain many of the body's functions.
cold hands and feet
decreased or no urine output
rapid heartbeat and breathing
Cardiogenic shock can be treated using blood-thinning medication, which makes the blood easier to pump. A type of medication called vasopressors may be used. Vasopressors help constrict (squeeze) the blood vessels, which increases the blood pressure and improves blood circulation.
Once the initial symptoms of cardiogenic shock have been stabilised, surgery may be required to improve the functioning of the heart. This may still include PCI, alongside the insertion of a small pump, known as an intra-aortic balloon pump. This can help improve the flow of blood away from the heart.
Another option is a coronary artery bypass graft (where a blood vessel from another part of your body is used to bypass any blockage).
A heart rupture is a serious and relatively common complication of heart attacks, occuring in around 1 in 10 cases.
A heart rupture is where the heart’s muscles, walls or valves rupture (split apart). It can occur if the heart is significantly damaged during a heart attack. It usually happens 1 to 5 days after a heart attack.
Symptoms are the same as those of cardiogenic shock. Open heart surgery is usually required to repair the damage.
The outlook for people who have a heart rupture is not good, and it is estimated that half of all people die within 5 days of the rupture occurring.
It is recommended you eat two to four portions of oily fish a week. Oily fish contains a type of fatty acid known as omega-3, which can help lower your cholesterol levels.
Good sources of omega-3 include:
Never take a food supplement without first consulting your GP. Some supplements, such as beta-carotene, could be potentially harmful.
It is also recommended that you eat a Mediterranean-style diet. This means eating more bread, fruit, vegetables and fish, and less meat. Replace butter and cheese with products based on vegetable and plant oil, such as olive oil.
For more dietary information and advice, see changing your diet after a heart attack.
If you smoke, it is strongly recommended you quit as soon as possible. TheSmokefree website can provide you with support and advice.
If you drink alcohol, do not exceed the recommended daily limits (no more than three to four units a day for men, and two to three units a day for women). A unit of alcohol is roughly half a pint of normal strength lager, a small glass of wine or a single measure (25ml) of spirits.
Regularly exceeding the recommended alcohol limits will raise your blood pressure and cholesterol level, thereby increasing your risk of another heart attack.
Avoid binge drinking (drinking lots of alcohol in a short space of time or drinking to get drunk). Binge drinking can cause a sudden and large rise in your blood pressure, which could be potentially dangerous.
Research has found that people who have had heart attacks and continue to binge drink are twice as likely to die of a serious health condition, such as another heart attack or stroke, compared to people who moderate their drinking after having a heart attack.
Contact your GP if you find it difficult to moderate your drinking. Counselling services and medications can help you reduce your alcohol
Regular physical activity
Adults should do at least 150 minutes (2 hours and 30 minutes) of moderate-intensity aerobic activity (such as cycling or fast walking) every week.
The level of activity should be strenuous enough to leave you slightly breathless.
If you find it difficult to achieve 150 minutes of activity a week, start at a level that you feel comfortable with (for example, 5-10 minutes of light exercise a day) and gradually increase the duration and intensity of your activity as your fitness begins to improve.
There are currently four types of medication widely used to reduce the risks of a heart attack.
angiotensin-converting enzyme (ACE) inhibitors
ACE inhibitors are often used to lower blood pressure, as they block the actions of some of the hormones that help regulate blood pressure. By stopping these hormones from working, the medicine helps reduce the amount of water in your blood and also widens your arteries, both of which will reduce your blood pressure.
ACE inhibitors have been known to reduce the supply of blood to the kidneys, which can reduce their efficiency. Therefore, blood and urine tests may be carried out before you start taking ACE inhibitors, to make sure there are no pre-existing problems with your kidneys.
Annual blood and urine tests may be required if you continue to use ACE inhibitors.
The side effects of ACE inhibitors can include:
tiredness or weakness
a persistent, dry cough
Most of these should pass within a few days, although some people continue to have a dry cough.
If ACE inhibitors are taken with other forms of medication, including over-the-counter (OTC) medicines, they can cause unpredictable effects.
Therefore, check with your GP or pharmacist before taking anything in combination with ACE inhibitors.
It is usually recommended that you begin taking ACE inhibitors immediately after having a heart attack and, in most cases, continue taking them indefinitely. In some individuals who prove intolerant of ACE inhibitors, a related alternative medication – an angiotensin receptor blocker (ARB) – may be prescribed.
Anti-platelets are a type of medication that can help prevent blood clots. They work by reducing the "stickiness" of platelets, which are tiny particles in the blood that help it to clot.
It is usually recommended you take low-dose aspirin, which has blood-thinning properties, as well as being a painkiller.
You may also be given an additional anti-platelet medication, such asclopidogrel, prasugrel or ticagrelor. These can also be used if you are allergic to aspirin.
Side effects can include:
bruising or bleeding
As with ACE inhibitors, treatment with anti-platelets usually begins immediately after a heart attack. The amount of time for which you are prescribed these medications can be anywhere between 4 weeks and 12 months, and depends on the type of heart attack you have had and the other treatment you have received.
It is usually recommended you take aspirin indefinitely. If you experience troublesome side effects due to aspirin, you should contact your GP for advice. Do not suddenly stop taking the aspirin, as this could increase your risk of another heart attack.
You may occasionally also be put on another blood thinning medication, called warfarin. This usually only happens if you have remained in an irregular heart rhythm (atrial fibrillation) or have sustained severe damage to your heart.
Excessive bleeding is the most serious side effect of warfarin. Seek immediate medical attention and have an urgent blood test if you experience any of the following side effects:
passing blood in your urine or faeces (stools or "poo")
passing black faeces
prolonged nosebleeds (that last longer than 10 minutes)
blood in your vomit
coughing up blood
in women, heavy or increased bleeding during your period or any other bleeding from the vagina
Immediate medical attention must also be sought if you:
are involved in major trauma (an accident)
experience a significant blow to the head
are unable to stop any bleeding
Beta-blockers are a type of medication used to protect the heart from further damage after a heart attack. They help relax the heart’s muscles so the heart beats slower and the blood pressure drops, both of which will help reduce the strain on your heart.
It is usually recommended that you begin treatment with beta-blockers as soon as your condition stabilises, and continue taking them indefinitely.
Fairly common side effects of beta-blockers include:
cold hands and feet
Less common side effects include:
inability to obtain or maintain an erection (erectile dysfunction or "impotence")
Beta-blockers can also interact with other medicines, causing possible adverse side effects.
Therefore, check with your GP or pharmacist before taking other medicines, including OTC medication, in combination with beta-blockers.
Statins are a type of medication used to lower your blood cholesterol level. This will help prevent further damage to your coronary arteries and should reduce the risk of another heart attack.
Statins block the effects of an enzyme in your liver called HMG-CoA reductase, which is used to make cholesterol.
Statins sometimes have mild side effects, including:
Occasionally, statins can cause muscle pain, weakness and tenderness. Contact your GP if you experience these symptoms as your dosage may need to be adjusted.
It is usually recommended that you take statins indefinitely.
Preventing a heart attack
Making lifestyle changes is the most effective way to prevent having a heart attack (or having another heart attack).
There are three main steps you can take to help prevent a heart attack (as well as stroke):
eat a healthy, balanced diet
try to keep your blood pressure at a healthy level
Eating an unhealthy diet high in fat will make your atherosclerosis(hardening of the arteries) worse and increase your risk of heart attack.
Continuing to eat high-fat foods will cause more fatty plaques to build up in your arteries. This is because fatty foods contain cholesterol.
There are two main types of cholesterol:
low-density lipoprotein (LDL) – this is mostly made up of fat plus a small amount of protein; this type of cholesterol can block your arteries, so it is often referred to as "bad cholesterol"
high-density lipoprotein (HDL) – this is mostly made up of protein plus a small amount of fat; this type of cholesterol can reduce deposits in your arteries, so is often referred to as "good cholesterol"
There are also two types of fat – saturated and unsaturated. Avoid foods containing high levels of saturated fat, as they increase levels of bad cholesterol in your blood.
Foods high in saturated fat include:
sausages and fatty cuts of meat
ghee (a type of butter often used in Indian cooking)
cakes and biscuits
foods that contain coconut or palm oil
Eating a small amount of unsaturated fat will increase the level of good cholesterol and help reduce any blockage in your arteries. Foods high in unsaturated fat include:
nuts and seeds
sunflower, rapeseed and olive oil
Smoking is a major risk factor for heart attacks because it causes atherosclerosis and raises blood pressure.
If you decide to stop smoking, your GP will be able to refer you to anStop Smoking Service, which will provide dedicated help and advice about the best ways to quit.
You can also call the Smoking Helpline on 0300 123 1014 (England only). Specially trained helpline staff will offer free expert advice and encouragement.
If you are committed to quitting but do not want to be referred to a stop smoking service, your GP should be able to prescribe medical treatment to help with withdrawal symptoms you may experience.
.High blood pressure
Persistent high blood pressure can put your arteries and heart under extra strain, increasing your risk of a heart attack.
High blood pressure can often be reduced by a healthy diet, moderating your intake of alcohol, maintaining a healthy weight and taking regular exercise.
The dietary advice above also applies if you have high blood pressure. In addition, cut down on the amount of salt in your food and eat plenty of fruit and vegetables.
Salt raises your blood pressure. The more salt you eat, the higher your blood pressure. You should aim to eat less than 6g (0.2oz) of salt a day, which is about a teaspoonful.
Eating a low-fat diet that includes lots of fibre – such as wholegrain rice, brad and pasta – and plenty of fruit and vegetables, has been proven to help lower blood pressure. Fruit and vegetables are full of vitamins, minerals and fibre, and help keep your body in good condition.
You should aim to eat five 80g portions of fruit and vegetables every day.
If you do need to shed some weight, it is worth remembering that losing just a few pounds will make a big difference to your blood pressure and overall health. Get tips on losing weight safely.
Being active and taking regular exercise will lower your blood pressure by keeping your heart and blood vessels in good condition. Regular exercise can also help you lose weight, which will help lower your blood pressure.
Low-impact activities such as walking, swimming and cycling are recommended. More strenuous activities, such as playing football and squash, may not be recommended. Check with the doctor in charge of your care.
For tips, read our pages on walking for health, swimming for fitnessand the benefits of cycling.