Quick answer
What is heart attack?
A heart attack happens when blood flow to the heart muscle is blocked, usually by a clot. Call 999 immediately for sudden chest pain, pressure or tightness that may spread to the arm, jaw or back, especially with sweating, nausea or breathlessness. Chew aspirin 300mg if available and not allergic — while waiting for the ambulance.
A heart attack is an emergency
A heart attack (myocardial infarction) happens when blood flow to part of the heart muscle is suddenly blocked, usually by a blood clot in a coronary artery. Without oxygen, heart muscle begins to die. Calling 999 immediately gives the best chance of survival and limits permanent damage.
Symptoms to recognise
The classic symptom is sudden chest pain, pressure or tightness — but symptoms vary:
- chest pain spreading to the left arm, jaw, neck or back
- feeling sick or vomiting
- sweating — a cold, clammy feeling
- sudden breathlessness
- overwhelming sense of anxiety or doom
- feeling very unwell without obvious explanation
Women may experience less typical symptoms — back pain, jaw pain, nausea, indigestion-like discomfort, or extreme fatigue without clear chest pain. Do not dismiss symptoms because they do not match the “classic” picture.
Symptoms usually last more than a few minutes and may not improve with rest.
What to do — call 999
- Call 999 — say you suspect a heart attack
- Keep the person calm — sitting upright is often most comfortable
- Chew 300mg aspirin if available, the person is conscious, not allergic, and has no serious bleeding risk or history of being told to avoid aspirin
- Do not drive to hospital unless absolutely no alternative — ambulance staff can start treatment en route
If the person becomes unconscious and is not breathing normally, start CPR and use a defibrillator if available.
What happens in hospital
Emergency treatment aims to restore blood flow — clot-busting drugs, angioplasty (opening the blocked artery with a balloon and stent), and medicines to protect the heart. Most people survive heart attacks, especially with fast treatment. Recovery includes cardiac rehabilitation — exercise, education and support.
Heart attack vs angina
Angina is chest pain from reduced blood flow that typically comes on with exertion and eases with rest or GTN spray. Heart attack pain is usually more severe, lasts longer, and may not settle with rest. When in doubt, call 999.
Reducing your risk
Major risk factors include high blood pressure, high cholesterol, smoking, diabetes, obesity, and family history. You can reduce risk by:
- stopping smoking
- taking prescribed statins and blood pressure medicines
- eating a heart-healthy diet — less saturated fat, salt and processed food
- regular physical activity
- maintaining a healthy weight
- limiting alcohol
NHS Health Checks identify cardiovascular risk from age 40 in England.
After a heart attack
Life after a heart attack involves medicines, lifestyle changes, and cardiac rehabilitation. Many people return to normal activities. Emotional responses — fear, low mood — are common and treatable. Speak to your GP or cardiac team about support.
Common questions
- What does a heart attack feel like?
- Sudden chest pain, pressure, heaviness or tightness — often described as an elephant on the chest. Pain may spread to the left arm, jaw, neck or back. Other symptoms include sweating, nausea, breathlessness and feeling suddenly very unwell. Some people — especially women — have milder or different symptoms.
- What should I do if I think someone is having a heart attack?
- Call 999 immediately. Keep them sitting and calm. If they are not allergic to aspirin and have no bleeding problems, give 300mg aspirin to chew (not swallow whole) unless they have been told to avoid it. Do not leave them alone.
- Are heart attack symptoms different in women?
- Women can have classic chest pain, but are more likely than men to experience nausea, indigestion-like pain, back or jaw pain, extreme fatigue, or breathlessness without obvious chest pain. Unusual sudden symptoms in someone at risk should be treated seriously.
- What is the difference between a heart attack and cardiac arrest?
- A heart attack is blocked blood flow to heart muscle — the heart usually keeps beating. Cardiac arrest is when the heart stops pumping effectively — the person collapses unconscious and needs CPR and a defibrillator immediately. A heart attack can lead to cardiac arrest.
- How can I reduce my heart attack risk?
- Stop smoking, control blood pressure and cholesterol, manage diabetes, maintain a healthy weight, exercise regularly, eat a balanced diet, and limit alcohol. Take prescribed medicines such as statins and blood pressure tablets as directed.