When a heart attack becomes a full cardiac arrest, the heart most often goes into uncoordinated electric activity called fibrillation. The heart twitches ineffectively and cannot pump blood. The AED delivers electric current to the heart muscle, momentarily stunning the heart, stopping all activity. This gives the heart an opportunity to resume beating effectively.

Often, it is not easy to tell. But there are symptoms people may have.

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Yes, because people with angina usually have coronary artery disease, they are at an increased risk for a heart attack. If angina episodes start happening more often, lasting longer, or occurring even when you're at rest (known as unstable angina), a heart attack may be about to happen. Studies indicate that every year, 3% to 3.5% of angina patients have heart attacks. If you feel you might be having a heart attack, call 911 or your local emergency number right away.

Even a stress test isn't 100% definitive. Certainly someone with a normal stress test is at lower risk than someone with an abnormal one. But plaque in an artery can sometimes go from an undetectable 20% blockage to a critical 99% blockage overnight, much like a volcano erupting. Unfortunately, this sort of situation is almost impossible to predict or prevent. Controlling blood pressure and cholesterol and taking aspirin can help, however. Yes and no.

A person diagnosed with CAD does not necessary mean that he is going to suffer from heart attack soon. Heart attack is a situation as explained earlier where blood supply to a certain part of the heart is completely cut off.

YES, constant high blood pressure hardens the arteries, by damaging the protective layer of the arteries. It increases the thickness of muscles of the heart, known concentric hypertrophy, as diagnosed on 2D Echo Cardiography. In many cases severe thickening leads to conditions of cardiac failure. It increases the burden on the heart, which has to work harder to maintain the normal blood flow.

YES, compared to non-diabetic, diabetics have two to three fold risk of dying from Coronary Artery Disease and they are prone to more of "Silent Heart Attack". They have severe form of blockages, involving are the major three arteries and also the disease is diffused in smaller vessels. High levels of sugar in the blood, causes damage to internal lining of the arteries, accelerating the process of blockages.

episode of angina is NOT a heart attack. However, people with angina report having a hard time telling the difference between angina symptoms and heart attack symptoms. Angina is a recurring pain or discomfort in the chest that happens when some part of the heart does not receive enough blood temporarily. A person may notice it during exertion (such as in climbing stairs). It is usually relieved within a few minutes by resting or by taking prescribed angina medicine.

A heart attack is an event that results in permanent heart damage or death. It is also known as a myocardial infarction, because part of the heart muscle (myocardium) may literally die (infarction). A heart attack occurs when one of the coronary arteries becomes severely or totally blocked, usually by a blood clot. When the heart muscle does not obtain the oxygen-rich blood that it needs, it will begin to die.

Yes, you can still have a heart attack. An ICD does not prevent a myocardial infarction, which is a blocked artery causing heart muscle tissue to die. Things like exercise, improved diet, reduced stress, and other lifestyle changes suggested in a cardiac rehab program will reduce chances for a heart attack. The ICD implant will save your life 99% of the time if you have a potentially lethal episode of arrhythmia. (According to current statistics.

I'm a 45-year-old woman and 30 lbs. overweight. If I were to make one change in my health behaviors, what do you suggest that I do or not do? I do not smoke. What is the relation of Hormone Replacement Therapy (HRT) to Coronary Artery Disease (CAD)? The newspapers suggest that one is at higher risk of having a heart attack if one takes HRT.

The signs of a heart attack usually occur at the time of the event and usually involve chest pain (also squeezing, pressure, burning, or heaviness). There can also be radiation of the pain to the left arm, throat or jaw, shortness of breath, dizziness, sweating, nausea, and fainting. Unfortunately sudden death due to cardiac arrest can also be the first symptom. There are also "silent heart attacks" where there are no symptoms but the heart attack is discovered on a routine EKG.

Emergency medical personnel-also called EMS, for emergency medical services-bring medical care to you. For example, they bring oxygen and medications. And they can actually restart someone’s heart if it stops after they arrive. Your wife/husband/friend/coworker can’t do that, or help you at all if they are driving. In the ambulance, there are enough people to give you the help you need and get you to the hospital right away.