Final answer:
The first action to take if someone is having a heart attack is to call 911 immediately. Subsequent steps include resting the person in a comfortable position, loosening any tight clothing, and potentially administering aspirin if advised. Start CPR only if the person is unresponsive and not breathing.
Step-by-step explanation:
If a person exhibits signs and symptoms of a heart attack, the first and most critical action is to Call 911 or the designated emergency number immediately. This ensures that professional medical help is on the way as quickly as possible. While waiting for emergency responders, the second step is to have the person rest in a comfortable position and loosen any constrictive clothing, which can help alleviate discomfort and prevent further distress. If trained and advised by emergency personnel, and if aspirin is not contraindicated, you may have the person chew a regular-strength aspirin tablet to help prevent blood clots, but only after calling for emergency help and if the person is not allergic or it's not otherwise contraindicated. CPR should only be initiated if the person is unresponsive and not breathing, indicating that their heart may have stopped, and you are trained to perform CPR.