Editor's note: Heart attack is a subject too vast for one column. We'll need three. This is the first installment.

If you think you're having a heart attack, should you take aspirin?A blood clot in a coronary artery narrowed by cholesterol and other substances is the usual cause of a heart attack. Aspirin keeps blood moving through constricted arteries. Therefore, paramedics may give aspirin when they respond to an emergency to treat a heart-attack victim.Aspirin reduces mortality from heart attacks. But taking aspirin is a subject you should discuss with your doctor. Aspirin could hurt you if your symptoms are caused by a different health problem.Doctors call a heart attack a "myocardial infarction." Loosely translated, the term means heart-muscle death. The clogged artery prevents oxygenated blood from nourishing the heart. This can lead to pain, the death of heart cells, scar tissue and fatal arrhythmias.About 1.1 million Americans have a heart attack every year. About 460,000 of those heart attacks are fatal. About half the fatalities happen within an hour after symptoms begin and before the victim gets to a hospital.How do you know if you're having a heart attack? Here are seven common warning signs:1. Most heart attacks involve discomfort in the center of the chest that lasts more than a few minutes. It may pause for a while and then restart. The discomfort can be in the form of pain or pressure. Some experience a squeezing or feeling of fullness.2. Pain in shoulders, arms, back, upper abdomen, neck and jaw3. Shortness of breath4. Cold sweat5. Nausea6. Lightheadedness7. AnxietyAngina pectoris is the medical term for chest pain or discomfort usually caused by coronary artery disease. Angina (pronounced "an-JI-nuh" or "AN-juh-nuh") is not a heart attack. However, there's a higher risk of a heart attack if you have angina.It is often difficult to tell the difference between a heart attack and angina. If you get angina, you should get medical attention immediately. Exertion brings on angina. It's usually relieved by resting or taking angina medicine.A heart attack can happen anytime - during exertion or at rest. Some heart attacks are like the ones you see in films and on stage; they're sudden and dramatic.However, most heart attacks build gradually over several hours. Many heart-attack victims have symptoms days or weeks in advance.If you think you're having a heart attack, call 9-1-1 immediately. There are drugs that break up clots and open arteries; they work best when given within the first hour after the onset of an attack.If emergency medical services are not available, ask someone to drive you to the hospital. You shouldn't drive yourself, unless you have no other choice.While it may seem macabre, planning for a heart attack is intelligent. Having a basic plan in place could save time and a life. Map out your steps if an attack happened at home or at work.For example, decide who would care for any dependents. And discussing aspirin with your doctor in advance will give you a clear course of action if you have a heart attack.The Times News Inc. and affiliates do not endorse or recommend any medical products, processes, or services or provide medical advice. The views of the author do not necessarily state or reflect those of the Times News. The article content is not intended as a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician, or other qualified health provider with any questions you may have regarding a medical condition.