Call 911 immediately. That single action matters more than anything else you do in the next few minutes. Every minute without treatment increases heart muscle damage, and research from the British Heart Foundation found that one death in every 12 patients could be prevented when treatment began within 90 minutes of first medical contact. Among patients who waited 150 to 180 minutes, a fifth died. Your job as a bystander is to get professional help moving toward the person as fast as possible, then keep them stable until it arrives.
Recognizing the Signs
The classic image of a heart attack is someone clutching their chest, but that’s not always what it looks like. Chest pain or pressure is the most common symptom in both men and women, but women are more likely to experience symptoms that seem unrelated: nausea, vomiting, pain in the neck, jaw, shoulder, upper back, or stomach, shortness of breath, unusual fatigue, dizziness, or what feels like heartburn. Women often describe chest discomfort as pressure or tightness rather than sharp pain, and these other symptoms can be more noticeable than any chest sensation.
It’s also possible to have a heart attack with no chest pain at all. Women are more likely to have symptoms while resting or even while asleep. People with diabetes have an increased risk of “silent” heart attacks, where the condition changes the way they perceive pain and symptoms go unnoticed. If something feels seriously wrong, even if it doesn’t match the textbook picture, treat it as an emergency.
Step by Step: What to Do
Once you suspect a heart attack, move through these steps in order:
- Call 911. Don’t delay this for any other action. The dispatcher needs to verify your address and will ask two key questions: Is the person conscious? Is the person breathing normally? Answer clearly, and the dispatcher will guide you from there. If you can’t get an ambulance, have someone else drive the person to the nearest hospital. Driving yourself should be a last resort.
- Help the person sit or lie down. The best position is one that reduces the heart’s workload and prevents a fall injury. Sitting on the floor with their back against a wall works well. It keeps them supported and makes it easier to reposition them for CPR if their condition worsens.
- Give aspirin only if directed. Aspirin helps prevent blood clotting and can reduce heart damage during an attack. Many experts recommend a full 325 mg tablet, chewed rather than swallowed whole so it enters the bloodstream faster. But don’t give aspirin on your own. Wait until the 911 dispatcher or a healthcare professional tells you to. And never give someone else’s nitroglycerin prescription.
- Stay with the person and monitor them. Keep them calm and still. Watch for changes in consciousness or breathing.
If the Person Becomes Unconscious
A heart attack can lead to cardiac arrest, where the heart stops pumping effectively. If the person collapses, doesn’t respond when you tap their shoulder and ask loudly “Are you OK?”, and isn’t breathing normally, you need to start CPR right away.
If you’re not trained in CPR, or you’re trained but rusty, do hands-only CPR. Place the heel of one hand in the center of the person’s chest, put your other hand on top, and push hard and fast at a rate of 100 to 120 compressions per minute. That’s roughly the tempo of the song “Stayin’ Alive.” Keep going without stopping until paramedics arrive.
If you’re trained and confident, start with 30 chest compressions followed by two rescue breaths, then repeat. Check for a pulse and breathing first, but spend no more than 10 seconds on that check. If there’s any doubt, start compressions.
How to Use an AED
Automated external defibrillators are designed for untrained bystanders. You don’t need medical knowledge to use one. If the person is unconscious and not breathing, and an AED is nearby (check lobbies, gyms, airports, schools), grab it and follow these steps:
- Turn it on. The device will give you voice prompts for every step.
- Expose the chest. Remove clothing covering the chest. Wipe the skin dry if needed.
- Attach the pads. Place one pad on the upper right side of the chest and the other on the lower left side, a few inches below the left armpit. If the pads might touch (on a small person), place one on the center of the chest and the other on the back between the shoulder blades.
- Let it analyze. Make sure nobody is touching the person. Say “Clear!” loudly.
- Deliver the shock if prompted. Again confirm nobody is touching the person, say “Clear!”, and press the shock button. The AED will only advise a shock if the heart rhythm needs it. You cannot accidentally shock someone who doesn’t need it.
Resume CPR immediately after the shock and continue until paramedics take over or the person starts breathing on their own.
Mistakes That Cost Time
The most dangerous mistake is hesitation. People wait because they’re not sure it’s really a heart attack, because they don’t want to overreact, or because they think the symptoms will pass. With heart muscle dying every minute, waiting is the worst option.
Other common errors: calling a friend or family member before calling 911, driving to the hospital instead of calling an ambulance (paramedics can begin treatment en route and alert the hospital before arrival), giving aspirin before calling 911 (call first, aspirin second), or giving the person someone else’s nitroglycerin. If the person takes prescribed nitroglycerin, they can use their own, but never share heart medications between people.
Finally, don’t let the person walk around, eat, or drink anything other than what emergency personnel recommend. Keep them still, keep them calm, and keep watching their breathing until help arrives.