The heart is a muscle that pumps blood around the body. It is made up of four separate chambers, two atria and two ventricles. Between the four chambers are valves that allow the blood to flow in one direction only-forward. With each beat of the heart, the right ventricle pumps deoxygenated blood into the arteries for circulation around the body. The each beat of the heart, the right ventricle pumps deoxygenated blood to the lungs while the left ventricle pumps oxygenated blood into the arteries for circulation around the body. The heart in turn depends on oxygenated blood coming to it through the coronary arteries (the arteries around the heart) for necessary oxygen and nutrients. If the coronary arteries are constricted due to atherosclerosis (a piece of tissue or air lodged in the artery), or a thrombus (a blood clot in the artery), the heart may be deprived of sufficient oxygen, causing a heart attack.

 Heart attack is a leading killer of both men and women in the United States. Each year, about 1.1 million people in the United States have heart attacks, and almost half of them die. Each year, about 1.1 million people in the United States have heart attacks, and almost half of them die.
         Myocardial infarction (MI) or acute myocardial infarction (AMI), commonly known as a heart attack is the interruption of blood supply to part of the heart, causing some heart cells to die. If blood flow is not restored within minutes, portions of the heart muscle begin to die, permanently damaging the heart muscle. Because this happens when the coronary arteries cannot provide the heart with sufficient oxygen, physicians also commonly refer to a heart attack as a “coronary”.
           There are three basic scenarios that can produce a heart attack. The first, and by far the most common, is partial or complete blockage of one of the arteries that supply the heart with oxygen, most often by a blood clot. In second heart attack scenario, an arrhythmia may set in, so that the heart is no longer pumping enough blood to ensure its own supply. In the third, a week spot in a blood vessel, called an aneurysm, may rupture, causing internal bleeding and disrupting normal blood flow.
           One third of all heart attacks occur without warning. The remainder are preceded by months or even year of symptoms, most commonly angina pectoris; chest pain that is typically aggravated by stress or physical exertion and relieved by rest. Like a heart attack, angina is caused by a lack of oxygen in the heart muscle, but the extent of oxygen deprivation is not sufficient to actually damage heart tissue. Many people complain of intermittent angina, shortness of breath, and/or unusual fatigue in the days or weeks leading up to a heart attack. A constant sensation of heartburn that persists for days and from which antacids provide no relief can be a sign of an impending heart attack. 

Cause and risk factor
            In general, people who are considered to be at greater than normal risk factor of heart disease those, who are following;

• Age (men 45 years and older; women 55 years or older, or after menopause)
• Diabetes
• Excessive alcohol consumption
• Family history of coronary heart disease
• High cholesterol
• High blood pressure
• Obesity
• Lack of physical activity
• Smoking
• Stress
• Drugs

Males are more at risk than females. One risk factor that has been receiving a great deal of attention is homocysteine, an amino acid formed as a result of the metabolism of another amino acid, methionine, which is essential for normal growth and normal metabolism. Homocysteine in turn is converted back into methionine in a constant recycling process. High Homocysteine level can be detected in over 20 percent of people with heart attack disease. High levels of blood fats—specifically; certain lipoproteins and triglycerides—are also associated with an increased risk factor of heart disease.
Sign and symptoms
Heart attack symptoms may be present for up to twelve hours. They may vary from person to person, and from heart attack to heart attack.
Followings are the symptoms and warning sign of the Heart attack disease, seek emergency call your doctor immediately; --------
Chest discomfort in the center of the chest, often described as heavy substernal pressure that makes it feel as if the chest is being squeezed.
 Pain or discomfort in one or both arms, the back, neck, j aw, or stomach.
Shortness of breath.
Sweating
Vomiting/ nausea.
Light-Headedness.

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• Dietary and Nutritional Recommendations
•           If you have suffered a heart attack, or if you are considered at risk for a heart attack, modify your diet. Important dietary measures include the following:
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Make sure your diet is high in fiber. Most beneficial fiber appears to come from whole grain break-fast cereals.
Eat lots of foods that are rich in vitaminsB6 and B12 (such as leafy green vegetables and fruits) and folic acid (such as breakfast cereals, asparagus, spinch, chickpeas and beans), which are needed to keep homocysteine levels in check.
Alfalfa, borage seed, horsetail, nettle and pau d’ arco are rich in minerals necessary for proper regulation of heart rhythm.
Green tea has superb antioxidant properties.
Include almonds, brewer’s yeast, grains, and sesame seeds in your diet.
Drink fresh vegetable juices. Drink steam-distilled water only.
 Don’t eat red meat, salt, sugars, or white flour.
Eliminate fried foods, coffee, black tea, colas and other stimulant from the diet.
Do not smoke and avoid secondhand smoke, alcohol 

• Learn to make heart-smart food substitutions, such as the following;

Instead of whole or 2 percent milk and cream, use 1 percent skim milk.
Instead of fried foods, eat baked, steamed, boiled, or broiled foods.
Instead of lard, butter, pal oil, or coconut oils, cook with unsaturated vegetable oils such as corn, olive, canola, safflower, sesame, soybean, sunflower, or peanut.
Instead of sauces, butter and salt, season vegetables with herbs and spices.
Instead of salted potato chips, eat low-fat, unsalted tortilla and potato chips and unsalted pretzels and popcorn.