The heart is a four-chambered muscular organ which works continuously through life. It receives impure (deoxygenated) blood from different parts of the body, and then pumps pure (oxygenated) blood to different organs. Heart attack or Myocardial Infarction refers to death of the cells (necrosis) of the heart muscle wall (myocardium) due to prolonged deprivation of blood supply and hence oxygen. It is one of the serious consequences of narrowing of the coronary artery (artery supplying the heart) by atheromatous plaque. This causes irreversible damage to heart muscles and can severely affect the functioning of the heart.
The chamber of the heart (left ventricle) which pumps blood to various parts of the body exerts the most and therefore needs more oxygen and blood supply for its sustenance. This makes it more common for the left ventricle to be commonly involved in heart attacks.
The severity of damage depends on the size of the coronary artery (bigger the artery, bigger the area of damage), number of arteries involved and presence of collateral (alternative routes) vessels. For the damage to be irreversible as much as 8 hours are required. Timely diagnosis and prompt treatment is therefore of utmost importance for preserving optimal myocardial functioning, better myocardial salvage and outcome.