The heart attack (myocardial infarction) is the death of, or damage to, part of the heart muscle because its blood supply is severely reduced or stopped. The heart blood supply stop because it has been starved of oxygen.
Severe problems linked to heart attack can include heart failure and life-threatening arrhythmias (irregular heartbeats). Heart failure is a condition in which the heart can’t pump enough blood throughout the body. Ventricular fibrillation is a serious arrhythmia that can cause death if not treated quickly.
A heart attack occurs when one or more of the coronary arteries that supply blood to the heart are completely blocked and blood to the heart muscle is cut off. The blockage is usually caused by atherosclerosis, the buildup of plaque in the artery walls, and/or by a blood clot in a coronary artery.
Acting fast at the first sign of heart attack symptoms can save your life and limit damage to your heart. Treatment is most effective when started within 1 hour of the beginning of symptoms.
Approximately six in 1,000 men in the UK aged between 30-69 years, have a heart attack each year. For women, the figure is lower, at two in 1,000. Men are three times more likely to suffer from a heart attack than women. A heart attack can cause serious complications and be potentially fatal. Half of those who die do so from cardiac arrest (when the heart stops completely) within three to four hours of the start of the attack.


THE SIMPTOM

The most common symptom of heart attack is chest pain or 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. The discomfort can feel like uncomfortable pressure, squeezing, fullness, or pain. It can be mild or severe. Heart attack pain can sometimes feel like indigestion or heartburn.
A heart attack usually occurs when a blood clot blocks the flow of blood through a coronary artery-a blood vessel that feeds blood to a part of the heart muscle. Interrupted blood flow to your heart can damage or destroy a part of the heart muscle.

HOW TO PREVENT?

Many heart attacks can be prevented through a healthy lifestyle, which can reduce the risk of developing coronary artery disease. For patients who have already had a heart attack, a healthy lifestyle and carefully following doctor's orders can prevent another heart attack such as :
1. A heart healthy lifestyle includes eating right, regular exercise, maintaining healthy weight, no smoking, moderate drinking, no illegal drugs, controlling hypertension, and managing stress.
2. A healthy diet includes a variety of foods that are low in fat (especially saturated fat), low in cholesterol, and high in fiber; plenty of fruits and vegetables; and limited sodium.
Saturated fat raises cholesterol, and, in excessive amounts, it increases the amount of the proteins in blood that form blood clots. Polyunsaturated and monounsaturated fats are relatively good for the heart.
Fat should comprise no more than 30 percent of total daily calories. In 2002, new evidence suggested that a diet rich in lutein, the pigment found in dark green leafy vegetables, helps artery walls fight plaque and lessens risk of heart attack.
Cholesterol should be limited to about 300 mg per day. Many popular lipid-lowering drugs can reduce LDL-cholesterol by an average of 25–30% when combined with a low-fat, low-cholesterol diet. Soluble fiber can also help lower cholesterol. Fruits and vegetables are rich in fiber, vitamins, and minerals, and they are low calorie and nearly fat free. Vitamin C and beta-carotene, found in many fruits and vegetables, keep LDL-cholesterol from turning into a form that damages coronary arteries. Excess sodium can increase the risk of high blood pressure, and daily intake should be limited to 2,400 mg—about the amount in a teaspoon of salt.
3. Regular aerobic exercise can lower blood pressure, help control weight, and increase HDL ("good") cholesterol. Moderate intensity aerobic exercise lasting about 30 minutes four or more times per week is recommended for maximum heart health, according to the Centers for Disease Control and Prevention and the American College of Sports Medicine. Three 10-minute exercise periods are also beneficial. Aerobic exercise—activities such as walking, jogging, and cycling—uses the large muscle groups and forces the body to use oxygen more efficiently. It can also include everyday activities such as active gardening, climbing stairs, or brisk housework.
4. Maintaining a desirable body weight is also important. About one quarter of all Americans are overweight, and nearly one-tenth are obese, according to the Surgeon General's Report on Nutrition and Health. People who are 20% or more over their ideal body weight have an increased risk of developing coronary artery disease. Losing weight can help reduce total and LDL cholesterol, reduce triglycerides, and boost relative levels of HDL cholesterol.
5. Smoking has many adverse effects on the heart. It increases the heart rate, constricts major arteries, and can create irregular heartbeats. It also raises blood pressure, contributes to the development of plaque, increases the formation of blood clots, and causes blood platelets to cluster and impede blood flow. Heart damage caused by smoking can be repaired by quitting—even heavy smokers can return to heart health. Several studies have shown that ex-smokers face the same risk of heart disease as non-smokers within five to 10 years of quitting.
6. Modest consumption of alcohol can actually protect against coronary artery disease. This is believed to be because alcohol raises HDL ("good") cholesterol levels in some patients. The American Heart Association defines moderate consumption as one ounce of alcohol per day—roughly one cocktail, one 8-ounce glass of wine, or two 12-ounce glasses of beer. Excessive drinking is always bad for the heart. It usually raises blood pressure, and can poison the heart and cause abnormal heart rhythms or even heart failure. Illegal drugs, like cocaine, can seriously harm the heart and should never be used.
7. Stress management means controlling mental and physical reactions to life's irritations and challenges. Techniques for controlling stress include thinking positively, getting enough sleep, exercising, and practicing relaxation techniques.


MEDICATIONS

Doctors typically prescribe drug therapy for people who've had a heart attack or who are at high risk of having one. Medications that help the heart function more effectively or reduce heart attack risk may include:
1. Blood-thinning medications. Aspirin makes your blood less "sticky" and likely to clot. Doctors recommend a daily aspirin for most people who've had a heart attack. Your doctor may, in some cases, prescribe a stronger blood thinner than aspirin.
Daily aspirin therapy has been proven to help prevent blood clots associated with atherosclerosis. It can also prevent heart attacks from recurring, prevent heart attacks from being fatal, and lower the risk of strokes. Surprisingly, a 2002 study found that aspirin therapy is underused by people at risk for heart attacks. Patients should consult their doctors before taking aspirin regularly.
2. Beta blockers. These drugs lower your heart rate and blood pressure, reducing demand on your heart and helping to prevent further heart attacks. Many patients will need to take beta blockers for the rest of their lives following a heart attack.
3. Angiotensin-converting enzyme (ACE) inhibitors. Doctors prescribe ACE inhibitors for most patients after heart attacks, especially for those who have had a moderate to severe heart attack that has reduced the heart's pumping capacity. These drugs allow blood to flow from your heart more easily, prevent some of the complications of heart attacks, and make a second heart attack less likely.
4. Cholesterol-lowering medications. A variety of medications, including statins, niacin, fibrates and bile acid sequestrants, can help lower your levels of unwanted blood cholesterol. The majority of people who've had a heart attack take cholesterol-lowering medications — drugs that help lower the risk of a second heart attack. These medications can help prevent future heart attacks even if your cholesterol was not very high at the time of the heart attack.