Heart attack: the signs and the steps

A heart attack (myocardial infarction) happens when blood flow to part of the heart muscle is blocked, usually by a blood clot. The longer the blockage lasts, the more heart muscle is damaged. Quick recognition and action save lives.

What is happening

Coronary arteries supply blood to the heart. When a plaque ruptures and a clot forms, the artery can be blocked. Without oxygen, heart muscle begins to die within minutes. Emergency treatment aims to restore blood flow as fast as possible.

Emergency warning

If you or someone else has symptoms of a heart attack, call your local emergency number immediately. Do not wait to see if symptoms pass.

Common signs

• Chest discomfort: pressure, squeezing, fullness, or pain in the center or left side of the chest, lasting more than a few minutes or going away and coming back.
• Discomfort in other upper body areas: one or both arms, the back, neck, jaw, or stomach.
• Shortness of breath, with or without chest discomfort.
• Cold sweat, nausea, or lightheadedness.
• In women, the elderly, and people with diabetes, symptoms may be subtler: unusual fatigue, indigestion-like discomfort, or shortness of breath without chest pain.

When in doubt, treat it as a heart attack and call for help.

What to do first

1. Call emergency services. State that you suspect a heart attack. Stay on the line and follow dispatcher instructions.
2. Have the person sit down and rest. Loosen tight clothing. Keep them calm.
3. If the person is conscious and not allergic, and if emergency dispatchers or a doctor have not said otherwise, give one adult aspirin (325 mg) to chew and swallow. Chewing speeds absorption. Do not give aspirin to someone who is unconscious or unable to swallow.
4. If the person becomes unresponsive and is not breathing normally, start CPR immediately. Push hard and fast in the center of the chest. Use an AED if one is available and follow its prompts.
5. Do not let the person drive themselves to the hospital. Wait for the ambulance; paramedics can start treatment en route.

What NOT to do

• Do not ignore symptoms or wait for them to go away.
• Do not give anything by mouth if the person is unconscious or having trouble swallowing.
• Do not try to drive yourself or let someone else drive you unless there is no other option and the person is fully conscious and stable.
• Do not delay calling for help because you are unsure. Emergency dispatchers can guide you.

When to call for help

Call emergency services immediately for chest pain or pressure lasting more than a few minutes, especially with shortness of breath, sweating, nausea, or pain spreading to the arm, jaw, or back. If symptoms are severe or the person feels very unwell, do not wait.

What to monitor

While waiting for help, stay with the person. Note the time symptoms started and whether they change. Be ready to report if the person becomes drowsy, confused, or unresponsive, and be prepared to start CPR.

How to prevent it

You can lower your risk by not smoking, managing blood pressure and cholesterol, staying physically active, eating a heart-healthy diet, limiting alcohol, and taking prescribed medications as directed. Know your numbers and attend regular check-ups.

Acting quickly is the single most important thing you can do. Call emergency services at the first sign of a possible heart attack.

This is general information and not a substitute for professional medical advice. In an emergency, call your local emergency number immediately.