First aid topic · Call emergency services · emergency

Heart attack

Also known as: myocardial infarction first aid, chest pain first aid

A coronary artery has blocked and heart muscle is dying. Survival and the amount of muscle saved depend on how fast the artery is reopened, so the first-aid job is recognition and a fast call, keeping the person still and calm, and being ready to start CPR.

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Emergency

Call emergency services (999 UK · 112 Europe · 911 North America) as soon as you recognise this, or have someone call while you act.

Recognise it

  • Central chest pain or pressure, like a tight band or heavy weight, lasting more than 15 minutes
  • Pain spreading to the arms (usually left), jaw, neck or back
  • Sweating, grey or pale skin, nausea, breathlessness, light-headedness
  • Women, older people and people with diabetes more often have breathlessness, indigestion-like discomfort or extreme tiredness without classic pain

What to do

  1. Call emergency services immediatelySay you suspect a heart attack. Do not drive them to hospital yourself unless there is no ambulance service: an ambulance brings a defibrillator and can start treatment and alert the catheter lab.
  2. Sit them down and keep them stillA half-sitting position with knees bent and back supported (the 'W' position) eases the heart's work. Loosen tight clothing. Reassure them.
  3. Give aspirin if available and not allergicOne 300 mg tablet chewed slowly (or 4 x 75 mg). It begins to stop platelets clumping in the blocked artery. Do not give it if they are allergic or have been told not to take aspirin.
  4. Help with their own GTN sprayIf they have angina medication, help them take it as prescribed.
  5. Watch and be readyStay with them. If they become unresponsive and stop breathing normally, start CPR and send for a defibrillator.

Do not

  • Do not let them walk about, eat, or 'see if it passes'
  • Do not give aspirin to someone with a known allergy or bleeding problem, or to children
  • Do not leave them alone

Get medical help when

  • Chest pain or discomfort lasting more than 15 minutes, or shorter but with breathlessness, sweating, collapse or a known heart condition

Why it works: the anatomy

The coronary arteries branch off the aorta just above the aortic valve and run across the heart's surface. A ruptured plaque in one of them triggers a clot that blocks flow; muscle downstream is ischaemic within seconds and starts dying within 20-30 minutes. Chewed aspirin reaches platelets within minutes; angioplasty within 90-120 minutes of the call saves the most muscle.

Educational content. Written to follow current resuscitation and first-aid guidance, but no page replaces a certified first-aid course. When in doubt, call emergency services.