Heart attack

Man holding chest

A heart attack happens when your heart muscle is starved of oxygen-rich blood.  This causes damage to your heart muscle.

A heart attack is life threatening. If you think you or anyone else is having a heart attack, you should phone 999 for an ambulance immediately.

Don’t delay calling 999 because you are uncertain or don't want to make a fuss. The sooner you get emergency treatment for a heart attack, the greater your chances of survival.

Symptoms of a heart attack 

Heart attack symptoms vary from one person to another. The most common signs are:

  • chest pain: tightness, heaviness or pain in your chest
  • pain in arms, neck, jaw, back or stomach: for some people, the pain or tightness is severe, while other people just feel uncomfortable
  • sweating
  • feeling light-headed
  • become short of breath
  • feeling nauseous or vomit

Should I take an aspirin if I think I am having a heart attack?

The first thing to do if you think you're having a heart attack is to phone 999 immediately for an ambulance.

You should then sit and rest while you wait for the ambulance to arrive. Do not get up and look around for an aspirin. This may put unnecessary strain on your heart.

If you are not allergic to aspirin and have some next to you, or if there is someone with you who can fetch them for you, chew one adult aspirin tablet (300mg).  However, if they are not nearby, the person should stay with you, they should not go hunting for aspirin.

What is the difference between a heart attack and a cardiac arrest?

A cardiac arrest happens when your heart stops pumping blood around your body. Although a heart attack can result in a cardiac arrest, they are two different things.

Someone who has had a cardiac arrest will be unconscious and won’t be breathing normally. If you see someone having a cardiac arrest, you can increase the person's chances of survival by phoning 999 and giving them immediate CPR.

Why do heart attacks happen?

Most heart attacks are caused by coronary heart disease. Coronary heart disease (CHD) is when your coronary arteries (the arteries that supply your heart muscle with oxygen-rich blood) become narrowed by a gradual build-up of fatty material within their walls.

If a piece of this fatty material (atheroma) breaks off it may cause a blood clot (blockage) to form. If it blocks your coronary artery and cuts off the supply of oxygen-rich blood to your heart muscle, this is a heart attack.

You might also hear a heart attack called acute coronary syndrome, myocardial infarction (MI) or coronary thrombosis.

Other rarer causes of a heart attack include spontaneous coronary artery dissection (SCAD) where one or more of the coronary arteries tear. 

How is a heart attack diagnosed?

When the ambulance arrives, the ambulance staff will;

  • examine you and monitor your heart rate and blood pressure,
  • do an electrocardiogram (ECG) in the ambulance,
  • assess your symptoms and medical history,
  • give pain relief if needed and oxygen if your oxygen level is too low,
  • give you aspirin if not given already,
  • transfer you to the most suitable hospital.

How is a heart attack treated?

When you arrive at hospital you will receive treatment for your blocked artery.

Either you will have a Primary Percutaneous Coronary Intervention (PPCI) which is an emergency coronary angioplasty. It involves reopening your blocked coronary artery, restoring the blood supply to the part of your heart that is starved of blood, which helps to save as much of your heart muscle as possible.

Or you will have Thrombolysis, also called a ‘clot buster’. This involves injecting a medicine into a vein to dissolve the blood clot and restore the blood supply to your heart. Sometimes this may be given to you in the ambulance.

In some types of heart attack people do not receive either of these two treatments because they will not benefit from them.

What happens to my heart after a heart attack?

A heart attack always causes some permanent damage to your heart muscle, but the sooner treatment is given, the more muscle it is possible to save.

If a heart attack damages a significant amount of your heart muscle, this can affect the pumping action of your heart. The term used to describe this is heart failure.  Also, some people continue to get angina after they have had treatment for their heart attack, because there is still narrowing of one or more of their coronary arteries.

Heart attack prevention

Living a healthy lifestyle can help prevent you from developing coronary heart disease and having a heart attack.

If you have had a heart attack you can dramatically reduce the risk of having another heart attack and future heart problems by keeping your heart healthy and taking your medicines.

If you're over 40 you should ask your doctor or nurse for a heart health check to assess your risk of having a heart attack in the next 10 years.

What about recovery?

A heart attack can be a frightening experience and it can take time to come to terms with what has happened. It's natural to be worried about your recovery and future.

Many people make a full recovery and within a few months are able to return to their normal activities.  However some people may find that they are not able to do as much as they previously did. Attending a cardiac rehabilitation course will increase your chances of getting back to normal as quickly as possible. 

Find out more about living with a heart condition

Find out more

Heart attack booklet

Designed for people who have had a heart attack or who have unstable angina, and their family and friends, this booklet explains what a heart attack and acute coronary syndrome is, treatments, recovery and rehabilitation.

Order or download

This booklet is also available to download in large print

Read more about heart attacks in Heart Matters magazine

Researching heart attack, saving lives

Sadly, not everyone survives a heart attack. But things are changing. Research helps us improve the treatment and prevention of heart attacks. That's why we fund scientists, like BHF Professor Steve Watson, to help us understand more about how we can treat heart attacks.