A heart attack occurs when blood flow to a section of heart muscle becomes blocked. If the flow of blood isn't restored quickly, the section of heart muscle becomes damaged from lack of oxygen and begins to die. Coronary arteries are blood vessels that supply the heart muscle with blood and oxygen. Blockage of a coronary artery deprives the heart muscle of blood and oxygen, causing injury to the heart muscle. Injury to the heart muscle causes chest pain and pressure. If blood flow is not restored within 20 to 40 minutes, irreversible death of the heart muscle will begin to occur. A heart attack often causes severe and crushing pain in the middle of the chest. This pain may then travel from the chest to the neck, jaw, ears, arms, and wrists. The person may also be cold and clammy, and their skin may appear pale and grey in color.

Causes of Heart Attack

High Blood Pressure, or hypertension, is a condition in which blood pressure levels are above the normal range. Blood pressures of 120-139 mm Hg and/or 80-89 mm Hg are considered prehypertension. Blood pressure is considered high if it is 140 mm Hg and/or 90 mm Hg or higher. High blood pressure increases the risk for heart attack, angina, stroke, kidney failure and peripheral artery disease (PAD). High blood pressure may also increase the risk of developing fatty deposit in arteries (atherosclerosis). The risk of heart failure also increases due to the increased workload that high blood pressure places on the heart.

Abnormal heart valves-Heart valve problems can result from disease, infection or a defect present at birth. When the valves don't open or close completely during each heartbeat, the heart muscle has to pump harder to keep the blood moving. If the workload becomes too great, heart failure results.

Block of arteries-A heart attack is caused by a block of the arteries which minimize the flow of blood with oxygen. Due to little amount of oxygen transported to the brain the stops and the person dies which we call it heart attack. The block of the arteries is a result of blood clot, cholesterol accumulation and fats. That is why doctors advise to eat healthy food with less fat to prevent heart attacks.

Heredity.-People whose parents have coronary artery disease are more likely to develop it. African Americans are also at increased risk, due to their higher rate of severe hypertension than whites.

Treatment

Lower the cholesterol level in your blood. Lowering your cholesterol, especially the level of "bad" LDL cholesterol, keeps plaques from building up in the coronary arteries. The total cholesterol level should be kept below 200 mg/dL, and the LDL cholesterol level below 130 mg/dL (under 100 mg/dL in those with known heart disease or diabetes). Some people are able to control their cholesterol level by changing what they eat, lose weight, and exercise more; others require medication.

Control blood pressure. Uncontrolled high blood pressure is one of the most common causes of heart disease.

Coronary artery bypass grafting is a type of open-heart surgery (the chest is opened). It is sometimes carried out if angioplasty is unsuccessful. It involves rerouting the blood around the affected coronary artery, using a replacement section of a blood vessel - the graft - which is usually taken from a leg vein. This helps people with dangerously narrow coronary arteries, especially if the left side of the heart is not pumping well. For more information, please see the BUPA separate fact sheet