The US National, Heart, Lung and Blood Institute has initiated a campaign to help people recognize if they are at risk of having a heart attack, what the early symptoms of an attack are, what to do, and so on. They have generously made their material available for use on health websites. We give below a slightly edited version of some of the sections. You can read the full version at their website, which is given at the end of the article, under Source. (Robert Griffith, Editor)

What is a heart attack?

Coronary heart disease (CHD) is caused by a narrowing of the coronary arteries that supply blood to the heart, and often results in a heart attack. Each year, about 1.1 million Americans suffer a heart attack, and about half of those attacks are fatal. About half of those deaths occur within 1 hour of the start of symptoms, and before the person reaches the hospital.

Fortunately, everyone can take steps to protect their heart -- and their life. The key is seeking medical care as soon as possible. A fast response to the signs of a heart attack is crucial to save lives and limit heart damage.

Who's At Risk?

Heart attacks strike both men and women. However, some persons are more likely than others to have one because of their "risk factors." Risk factors are behaviors or conditions that increase the chance of a disease. Some of them are beyond your control, but most can be modified to help you lower your risk of having a first -- or repeat -- heart attack. Risk factors for heart attack are:

1. Factors you cannot control:

• Pre-existing coronary heart diseases, including a previous heart attack, a prior angioplasty or bypass surgery, or angina.
• Age-In men, the risk increases after age 45; in women, the risk increases after age 55.
• Family history of early heart disease - a father or brother diagnosed before age 55, or a mother or sister diagnosed before age 65.

2. Factors you can control:

• Smoking
• High blood pressure
• High blood cholesterol
• Overweight and obesity
• Physical inactivity
• Diabetes

Risk factors do not add their effects in a simple way. Rather, they multiply each other's effects. So, it's very important to prevent or control the risk factors that can be modified.

Limiting the damage

Treatments for a heart attack work to open the blocked artery to restore blood flow as fast as possible, in order to prevent or limit damage to the heart muscle, and to lessen the chance of a repeat attack. The main treatments are thrombolytic ("clot-busting") therapy, other medications, and special procedures, such as angioplasty and coronary artery bypass surgery. To be most effective, these treatments must be given fast -- within 1 hour of the start of heart attack symptoms. Acting fast can save your life and limit damage to your heart.

Warning signs

If you learn the signs of a heart attack and what steps to take, you can save a life -- maybe your own. Women may not think they're at risk of having a heart attack -- but they are.

What are the signs of a heart attack? Many people think a heart attack is sudden and intense, like a "movie" heart attack, where a person clutches his chest and keels over. The truth is that many heart attacks start slowly, as a mild pain or discomfort. If you feel such a symptom, you may not be sure what's wrong. Your symptoms may even come and go. Even those who have already had one heart attack may not recognize their symptoms, because the next attack can have entirely different ones.

It's vital that everyone learn the warning signs of a heart attack. These are:

• Chest discomfort. Most heart attacks involve discomfort in the center of the chest that lasts for more than a few minutes, or goes away and comes back. It can feel like uncomfortable pressure, squeezing, fullness, or pain.
• Discomfort in other areas of the upper body. This can include pain or discomfort in one or both arms, the back, neck, jaw, or stomach.
• Shortness of breath. This often accompanies chest discomfort. But it also can occur before chest discomfort.
• Other symptoms. These may include breaking out in a cold sweat, nausea, or light-headedness.

Learn the signs -- but also remember: Even if you're not sure it's a heart attack, you should still have it checked out. Fast action can save lives -- maybe your own.

If you're a woman, you may believe you're not as vulnerable to a heart attack as a man -- but you are. Women account for nearly half of all heart attack deaths. Heart disease is the number one killer of both women and men. Women, too, should learn the heart attack warning signs.

There are differences in how women and men respond to a heart attack. Women are less likely than men to believe they're having a heart attack and more likely to delay in seeking emergency treatment. Further, women tend to be about 10 years older than men when they have a heart attack. They are more likely to have other conditions, such as diabetes, high blood pressure, and congestive heart failure -- making it all the more vital that they get proper treatment fast.

As with men, the most common symptom is chest pain or discomfort. But women are more likely than men to experience some of the other common symptoms, particularly shortness of breath, nausea/vomiting, and back or jaw pain.

If you feel heart attack symptoms, do not delay. Remember, minutes matter! -- 5 minutes at most -- before calling the ambulance, or 911.

Surviving

How do you survive a heart attack? Fast action is your best weapon. Clot-busting drugs and other artery-opening treatments can stop a heart attack in its tracks. They can prevent or limit damage to the heart -- but they need to be given immediately after symptoms begin. To be most effective, they need to be given ideally within 1 hour of the start of heart attack symptoms.

Testing

Once you get help, you will undergo tests to see if a heart attack has actually occurred. Some are done at the hospital, while emergency medical personnel who come in the ambulance will do others. Key heart attack tests are:

• Electrocardiogram (ECG or EKG). This is a graphic record of the electrical activity of the heart as it beats. The ECG can detect abnormal heartbeats, some areas of damage, inadequate blood flow, and heart enlargement.
• Blood test. A blood test will be done routinely to check for enzymes or other substances that are released when heart muscle cells begin to die. These are "markers" of the amount of damage to your heart.
• Nuclear scan. This test shows any areas of the heart that lack blood flow and are damaged. It can also reveal problems with the heart's pumping action. A small amount of radioactive material is injected into an arm vein. A scanning camera positioned over the heart records whether the material is taken up by the heart muscle (healthy areas) or not (damaged areas). This test can be done at rest and during exercise, enhancing the usefulness of its results.
• Coronary angiography (or arteriography). This test is used to check blockages and narrowed areas inside coronary arteries. A fine tube (catheter) is threaded through an artery of an arm or leg up into the heart. A dye that shows up on X-ray is then injected into the blood vessel, and the vessels and heart are filmed as the heart pumps. The picture is called an angiogram or arteriogram.

Reduce your risk

You can reduce your risk of having a heart attack - even if you already have CHD or have had a previous heart attack. The key is to take steps to prevent or control your heart disease risk factors. The six key steps are those necessary to counteract the risks we listed above:

• Stop smoking
• Lower your blood pressure, if it's high.
• Reduce your blood cholesterol
• Aim for a healthy weight
• Be physically active each day
• Mange diabetes, if you have it.

Heart disease and medications

Sometimes, medications may be needed to help prevent or control CHD and so reduce the risk of a first or repeat heart attack. But, if medications are needed, lifestyle changes still must be undertaken. Remember, always take medications as directed by your physician.

Drugs used to treat CHD include:

• Aspirin -- helps to lower the risk of a heart attack for those who have already had one. It also helps to keep arteries open in those who have had a previous heart bypass or other artery-opening procedure such as coronary angioplasty. Because of its risks, the US Food and Drug Administration has not approved aspirin for preventing heart attacks in healthy individuals. Talk to your doctor about whether taking aspirin is right for you.
• Digitalis -- makes the heart contract harder and is used when the heart's pumping function has been weakened; it also slows some fast heart rhythms.
• ACE (angiotensin converting enzyme) inhibitor -- stops the production of a chemical that makes blood vessels narrow and is used to help control high blood pressure and for damaged heart muscle. It may be prescribed after a heart attack to help the heart pump blood better, and in persons with heart failure.
• Beta blocker -- slows the heart and makes it beat with less force, so blood pressure drops and the heart works less hard. It is used for high blood pressure, chest pain, and to prevent a repeat heart attack.
• Nitrate (including nitroglycerine) -- relaxes blood vessels and stops chest pain.
• Calcium channel blocker -- relaxes blood vessels and is used for high blood pressure and chest pain.
• Diuretic -- decreases fluid in the body and is used for high blood pressure. Diuretics are sometimes referred to as "water pills."
• Blood cholesterol-lowering agents -- decrease LDL cholesterol levels in the blood.
• Thrombolytic agents -- also called "clot busting drugs," they are given during a heart attack to break up a blood clot in a coronary artery in order to restore blood flow.

Drugs can cause side effects. If side effects occur, report them to your doctor. Often, a change in the dose or type of a medication, or the use of a combination of drugs can stop the side effect.