A heart attack leads to permanent heart damage or death. It is also known as a myocardial infarction, because part of the heart muscle (myocardium) might die (infarction). A heart attack occurs when one of the coronary arteries becomes severely or completely blocked, usually due to a blood clot.

The severity of a heart attack generally depends on how much of the heart muscle is injured during the heart attack.

The main symptom of a heart attack is chest pain that is unrelieved by rest and often spreads or radiates through the upper body to the arms, neck, shoulders or jaw.

Other symptoms include shortness of breath, palpitations, dizziness, sweating or nausea. In contrast with men, women are more likely to feel fatigue or nausea prior to a heart attack. In diabetic patients, the symptoms may be very mild or silent.

Risk factors for heart disease include: hypertension (high blood pressure), hyperlipidemia (high cholesterol), a family history of heart disease (particularly premature coronary artery disease), cigarette smoking, a sedentary lifestyle and diabetes.

Smoking - Smoking increases the risk of heart attack three to four times over non-smokers. Smoking can cause artery muscles to contract, reducing blood flow to the heart.

High Blood Pressure - High blood pressure causes blood to press too hard against the walls of the arteries, damaging the arteries and promoting the development of hardening of the coronary arteries.

High Cholesterol - Cholesterol is a fat substance found in foods of animal origin. High levels of cholesterol contribute to the formation of fatty build-up along the inside lining of the arteries, blocking the flow of blood.

High Triglycerides - Triglycerides are a fat found in the blood and are the end products of sugar breakdown that contributes to plaque formation. Limited intake of sugars, starches and alcohol is recommended.

Diabetes - Diabetics are more than twice as likely to develop heart disease. Diabetes damages the artery walls and increases the risk of plaque formation. Diabetics need to keep their blood sugar levels normal and control their cholesterol and triglycerides.

Excessive Alcohol and Caffeine Intake - Alcohol and caffeine can raise the cholesterol by raising the fat level in the blood. Alcohol consumption must be limited. Limit beverages with caffeine to two cups per day.

Obesity - Being overweight puts a direct strain on the heart. In case of overweight people, the heart has to work harder to supply the extra tissues with blood. Losing weight decreases the cholesterol and lowers the blood pressure.

Lack of Proper Exercise - A balance of rest, relaxation and activity are needed for a healthy body. A balanced exercise programme is recommended.

Angina pain is not the same as a heart attack. However, people with angina have difficulty in telling the difference between angina symptoms and symptoms of a heart attack. 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 while climbing stairs. It is usually relieved within a few minutes by resting or by taking medicines prescribed for angina. People who have been diagnosed with angina, though, have a greater risk of a heart attack than other people. Prolonged angina pain can lead to a heart attack.

Heart failure is the inability of the heart to pump out sufficient blood to meet the needs of the body. The pumping function of the heart is divided into two phases: first, the ability of the heart to relax properly so that blood can return into the relaxed heart called diastole and secondly, the ability to be actively pumped out to the body called systole. When the heart begins to malfunction, both of these functions become abnormal, usually.

Blood pressure represents a measure of the amount of blood pumped out by the heart and then the vessels into which this blood is pumped. The amount of blood pumped out by the heart is controlled by two factors: first, the volume of blood returning to the heart from the rest of the body and secondly, the actual pumping of the heart itself.

Medication to lower cholesterol can prevent heart attacks and save the lives of people who are at high risk for a heart attack. That's why people who have already had one heart attack need to be treated to lower their cholesterol in order to prevent another one.

Heart-healthy diet refers to a diet that is low in sodium, cholesterol and fat. Foods that best meet this requirement are whole grains, fruits, and vegetables. A diet high in sodium, fat and cholesterol is associated with higher blood pressure, increased weight and elevated blood cholesterol levels, all of which increase the chances that atherosclerosis will occur. Atherosclerosis is a build-up of fatty deposits in the artery walls.

Cardiac rehabilitation is a comprehensive program consisting of monitored exercise, health education and support. It helps people who are recovering from or experiencing a heart problem return to an active life.