A heart attack is typically the result of plaque -- a buildup of cholesterol or fat -- forming on the walls of arteries. Occasionally, a piece breaks away, blocks blood flow and destroys part of the heart muscle. Most heart attacks are limited and survivable. However, in severe instances a heart attack results in cardiac arrest -- a complete shutdown of the organ resulting in death.  A heart attack is different from atrial fibrillation, an irregular, rapid heartbeat caused by shifting electrical signals in the body. Atrial fibrillation can cause blood clots, which may lead to a stroke.

 Men over 45 and women over 55 are at greater risk for heart attacks than younger people. Using tobacco and/or drugs, especially cocaine, also contributes to heart attacks. Other factors that up the risk include obesity, diabetes, lack of physical activity, family history, stress and autoimmune disorders such as lupus or rheumatoid arthritis.

SEEK HELP FOR THESE SYMPTOMS:

* Pain, pressure, squeezing or tightness in the chest or arms that spreads to the back, jaw or neck

* Cold sweat

* Fatigue

* Abdominal pain, heartburn, indigestion or nausea

* Shortness of breath and lightheadedness or sudden dizziness

TREATMENT:

Immediately call for emergency help, as heart tissue begins to die when blood flow is interrupted. If you have nitroglycerin that has been prescribed by a physician, take it.

Doctors may give you drugs that dissolve or prevent blood clots, or other blood-thinning medications. Cardiologists may also prescribe betablockers or ACE inhibitors, which help the heart relax and can prevent further heart damage. Other possible medications include statins, which help control blood cholesterol.

Surgical procedures include coronary angioplasty and stenting, which reopen blocked arteries. Depending on the damage, a doctor may perform a coronary bypass, which involves transplanting a vein or artery as an alternative route for blood to reach the heart.