Heart attack

Expert reviewers Dr Tim Cripps, Consultant Cardiologist and Dr Melanie Hill, Bupa Clinics GP
Next review due July 2023

A heart attack is a serious medical condition which happens when the blood supply to part of your heart gets blocked. Your heart muscle then becomes damaged because of lack of oxygen. The medical name for a heart attack is myocardial infarction, or MI.

A heart attack can be life-threatening: phone 999 and ask for an ambulance if you think you, or someone you’re with, may be having one. The sooner you get treatment for a heart attack, the better your chances of survival.

What is a heart attack?

Heart attacks are usually caused by coronary heart disease (CHD). This is when the coronary arteries, which supply your heart muscle with blood and oxygen, develop build-ups of fatty deposits called plaques. This causes the coronary arteries to narrow. The plaques can also rupture, causing blood clots to form. Together the plaques and blood clots can completely block your coronary artery, stopping blood flow to your heart muscle and causing a heart attack.

The risk of having a heart attack increases as you get older, and men tend to get them at a younger age than women.

Symptoms of a heart attack

A heart attack may happen without any warning. The symptoms of a heart attack can vary from person to person. It isn’t always obvious that you’re having one. Often people wait too long before calling for help because they aren’t sure what’s happening.

An image showing pain in your chest, a symptom of a heart attack
An image showing pain in your abdomen, a symptom of a heart attack
An image showing someone feeling breathless, a symptom of a heart attack
An image showing someone feeling dizzy, a symptom of a heart attack
An image showing someone feeling sick, a symptom of a heart attack

If you have a heart attack, you’ll most likely feel pain or discomfort in the middle of your chest. It may spread up to your jaw, neck and shoulders, and then down to your arms (usually your left arm). The pain is often described as a sensation of heaviness, pressure, tightness or squeezing, aching or burning. The pain doesn’t always come on suddenly, as you might expect. For some, the pain may be mild, and come on slowly.

Other symptoms may include:

  • pain or discomfort in your abdomen, like indigestion
  • feeling breathless
  • feeling sweaty, light-headed or dizzy
  • feeling sick or vomiting

Women, older people and people with diabetes are more likely to have these other symptoms. See our FAQ for information about heart attacks in women.

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What to do if someone is having a heart attack

If you suspect that you or someone you’re with is having a heart attack, call 999 for emergency medical help immediately. You can do the following while you’re waiting for an ambulance.

  • If you have aspirin available and you’re not allergic to it, chew a single 300mg tablet, or give this to the person you’re helping.
  • Sit and rest in a position that’s most comfortable for you until the ambulance arrives (or assist someone else in doing this).
  • If a person you’re helping becomes unconscious and stops breathing, giving them CPR (cardiopulmonary resuscitation) can help to keep oxygen circulating around their body until an ambulance arrives.

Diagnosis of a heart attack

A paramedic or doctor at hospital will give you an ECG (electrocardiogram) as soon as possible. An ECG checks the electrical activity of your heart, and can often show whether or not you’re having a heart attack. If the ECG confirms a heart attack, you may be given treatment straightaway, before waiting for results of any other tests.

Your doctor may recommend other tests, either immediately or over the next few days in hospital. These include the following.

  • Blood tests, including tests for a protein called troponin. Your heart produces troponin when your heart muscle is damaged. Levels in your blood increase within hours of a heart attack and then fall again.
  • A chest X-ray. This will help your doctor see whether there might be a cause for your chest pain other than a heart attack. It also checks for fluid in your lungs, which might happen if your heart isn’t working well after a heart attack.
  • A coronary angiogram – your doctor will give you an injection of a special dye into your coronary arteries to make them clearly visible on X-rays. This test can show where there are blockages or narrowings in your coronary arteries.
  • An echocardiogram – this uses ultrasound (sound waves) to check the structure of your heart. It can detect how much damage there’s been to your heart muscle, any complications and how well your heart is working.

Treatment of a heart attack

How you are treated in hospital will depend on how severe your heart attack is and how long it is since your symptoms started.

If you’re having the most serious type of heart attack, when your coronary artery has been completely blocked, your doctor may recommend treatment to restore blood flow to the affected heart muscle. There are two main ways to do this.

  • A coronary angioplasty (also known as a primary angioplasty or percutaneous coronary intervention (PCI). This involves widening your narrowed or blocked coronary artery by inflating a balloon inside it. Your doctor will usually also insert a wire mesh tube called a stent to hold your coronary artery open. This is usually the best treatment to have, if it’s available quickly.
  • Thrombolysis. This is an injection of medicines that break down the clot in your coronary artery, sometimes called a ‘clot buster’. The medicine is given through an injection into a vein in your arm. You may be given this if you aren’t able to get a coronary angioplasty in enough time.

Sometimes you may need further surgery once you’ve recovered from the initial heart attack. This might include more angioplasty or a coronary artery bypass graft (CABG). CABG is an operation to bypass a narrowed section of your coronary artery using a blood vessel from your chest, leg or arm. This diverts the flow of blood around your narrowed or blocked coronary artery.

After treatment of a heart attack

Once you’ve recovered from a heart attack, your doctor will recommend a range of measures to try to reduce your risk of having another one. These may include medicines, lifestyle changes and taking part in a cardiac rehabilitation programme. See Prevention section below for more information on lifestyle changes you can make.


Your doctor will prescribe you medicines to start taking in hospital. You’ll usually need to continue taking these long term. These may include:

  • antiplatelet medicines (usually aspirin with another antiplatelet medicine), which help prevent clots forming
  • statins to help keep your cholesterol low, which can clog up your arteries
  • angiotensin-converting enzyme (ACE) inhibitors to improve blood flow to your heart muscle
  • beta-blockers, which slow down your heart rate, reducing the work it has to do

Always make sure you’ve spoken to your doctor or pharmacist about how to take your medicines, and read the patient information leaflet if you need any more information.

Cardiac rehabilitation

Cardiac rehabilitation programmes aim to help you recover from your heart attack and get back to as full a life as possible afterwards. The programmes can reduce your risk of dying after a heart attack so it’s an important part of your treatment.

Cardiac rehabilitation programmes include an exercise component with a range of different activities, which will be tailored to you. They may also include education and information sessions about your condition and support with things like giving up smoking, stress management and changing your diet. Cardiac rehabilitation may start while you’re still in hospital, and you should be invited to a session soon after you’re discharged.

Causes of a heart attack

Certain factors can make you more likely to develop coronary heart disease, which then puts you at a greater risk of a heart attack. These include if you:

There are ways you can help yourself by reducing these risks – see our section on prevention of heart attack below.

There are also factors that are out of our control, for instance having a family history of coronary heart disease at a young age, getting older and being male. If these factors apply to you, it’s even more important that you reduce your other risks factors of heart attack as much as you can, by making lifestyle changes.

Complications of a heart attack

With prompt treatment, many people these days survive a heart attack and go on to make a good recovery. But it’s important to be aware that a heart attack can lead to more serious problems, either straightaway, or in the long term.

Without treatment, a heart attack may cause permanent damage to the structure of your heart. If there is a lot of damage, your heart won’t be able to work properly anymore, and this can be fatal. Other complications may include the following.

  • Arrhythmia (abnormal heart rhythms). Your heart may beat too fast, or too slowly, or the rhythm may become irregular. Arrhythmias can be life-threatening.
  • Angina, pain or discomfort in your chest which carries on after your heart attack, especially when you’re active or exercising. This is a sign of reduced oxygen supply to your heart.
  • Heart failure, when it’s more difficult for your heart to pump enough blood and oxygen around your body. This is because the heart attack can damage your heart muscle and make it weaker.
  • Depression or feeling low. Many people feel depressed after having a heart attack. You may be worried about having another heart attack or concerned about your recovery. If you’re feeling anxious, speak to your doctor for advice.

Treatments are available to help manage all of these complications.

Prevention of a heart attack

You may be able to reduce your risk of developing coronary heart disease and having a heart attack by making some healthy lifestyle changes. These include the following.

  • If you smoke, giving up. Your doctor can offer you support to help with this.
  • Losing excess weight if you’re overweight or obese.
  • Doing regular physical activity – aim for at least 150 minutes (two and a half hours) of moderate-intensity exercise over the course of a week, or 75 minutes of more vigorous activity.
  • Eating a healthy, balanced diet that’s low in saturated fat and salt, and includes at least five portions of fruit and vegetables a day. Aim to have two portions of fish (one oily) a week.
  • Not drinking alcohol to excess. For both men and women this means not regularly drinking more than 14 units of alcohol a week.
  • Taking any medication you’re prescribed to control high blood pressure, high cholesterol and diabetes.

If you’ve previously had a heart attack, these measures can reduce your risk of having another one. Your doctor will also prescribe medicines to reduce your risk of further heart attacks. It’s important that you take these as prescribed.

If you have any questions about your medicines or how to take them, ask your pharmacist.

If you have certain risk factors, such as a family history of heart disease, your GP may be able to arrange for you to have a health check to assess your risk of heart attack. Everyone over the age of 40 is eligible for a free health check too.

Frequently asked questions

  • Although heart attacks are more common in men, it’s important to know that women get them too. For every 100 people who have a heart attack, 40 are women. In fact, women are more likely to die from a heart attack than men.

    Like men, the most common symptom of heart attack in women is a dull, heavy chest pain. But women are more likely to have more less typical symptoms too – such as abdominal discomfort, feeling sick and vomiting.

    Women tend to wait longer before calling for emergency medical help when they have heart attack symptoms. This may be because they don’t think it could possibly be a heart attack, or they don’t want to cause a fuss. This delay can have a big effect on whether you survive a heart attack.

    If you think you’re having a heart attack, call 999 for emergency medical attention.

  • Many people make a full recovery after having a heart attack. Others find that they can’t do as much as they used to before, or go on to have further problems. How well you recover after a heart attack depends on lots of things, such as how severe a heart attack it was and the treatment received. How old you are, and whether you have any other underlying conditions, also makes a difference.

    It’s important to remember that your recovery may take several months as your body needs time to heal. Your best chance of getting back to normal is to follow your doctor’s advice about lifestyle changes and take any medications that they prescribe. It’s also really important to go to your cardiac rehabilitation sessions where you’ll get lots of help, advice and support for your recovery.

    Returning to work can be an important part of your recovery. It can help with your general self-esteem and mental wellbeing. How long this takes will depend on your heart condition, what treatment you had and what work you do. If your job involves sitting at a desk, you’ll probably be ready to go back much sooner than if your job is more physically demanding. Talk to your doctor and your employer about what’s best for you, and whether you need to make any adjustments to your role.

  • Chest pain and other symptoms such as breathlessness and feeling dizzy aren’t always symptoms of heart attack. They can also be symptoms of other things, such as panic attacks, muscular and joint problems, gastro-oesophageal reflux disease (GORD) and other problems affecting your heart and lungs. But there’s no way to know for certain whether you’re having a heart attack if you develop these symptoms, so it’s important not to delay seeking help. Only a doctor will be able to tell you once they’ve done some tests.

    If you think you, or someone you’re with could be having a heart attack, get emergency help immediately. Don’t wait. The sooner you get medical help the better the chance of surviving and making a full recovery.

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  • Reviewed by Pippa Coulter, Freelance Health Editor, July 2020
    Expert reviewers Dr Tim Cripps, Consultant Cardiologist and Dr Melanie Hill, Bupa Clinics GP
    Next review due July 2023