Warning signs
- Pressure, squeezing, fullness, or pain in the center of the chest, often lasting more than a few minutes or going away and coming back.
- Pain or discomfort in one or both arms, the back, neck, jaw, or stomach.
- Shortness of breath, with or without chest discomfort.
- A cold sweat, nausea, or lightheadedness.
Women, older adults, and people with diabetes sometimes have less typical signs: unusual fatigue, nausea, or shortness of breath with milder chest pressure. Those signs still justify a 911 call.
What is happening
A heart attack usually means a coronary artery is blocked and part of the heart muscle is not getting enough blood. The person is often awake. Cardiac arrest means the heart has stopped pumping effectively. The person is unresponsive and not breathing normally, and needs CPR.
If a person with heart attack symptoms becomes unresponsive and stops breathing normally, start CPR and use an AED if one is available. Until then, help them rest in a comfortable position and loosen tight clothing. Do not give food or drink.
Aspirin is sometimes used by emergency dispatchers for a suspected heart attack. Take it only if the dispatcher or a clinician tells you to, and only if you are not allergic and have not been told to avoid it.
More detail is on the CDC heart attack page and the American Heart Association warning-signs page.