A heart attack is the result of blockages in the coronary arteries that supply blood and oxygen to the heart. These blockages pause or cease blood flow into the heart, leading to pain in and the eventual death of the heart muscle. Since the heart is the organ that filters good blood from bad and supplies all vital organs, it is essential that there is no stoppage in the blood supply to the heart itself.

The blockage in the coronary arteries is caused by the accumulation of fatty substances or cholesterol in the walls of the arteries. Gradually, these substances harden into plaque and attract elements of blood. In time, the plaque breaks open. A blood clot seals the open hole and further reduces blood flow. All these narrow the width of the artery, leaving little or no room for blood to pass through. This condition is called ischemia. Ischemia causes pain, a common symptom of heart attack.

Diseases caused due to formation of plaque are called coronary heart diseases. These include heart attacks, chest pain, palpitation of the heart and so on.

Cells in the heart muscle die even with minimal stoppage of the blood supply. This could result in the death or disability in the person. Eventually, after around eight hours, the muscle is replaced with scar tissue.

Apart from genetic reasons, factors such as improper lifestyle, smoking, high blood pressure and diabetes accelerate atherosclerosis.

In medical terms, a heart attack is called myocardial infarction, since there is no blood supply to the cells of the heart muscle