Myocardial ischemia

Ischemia is a condition, in which there is discrepancy between oxygen requirement at a given time and the amount of oxygen supplied to the heart. Such discrepancy is usually due to a partial narrowing of an artery caused in most cases by the formation of a lipid plaque in the arterial wall. Narrowing of an artery (stenosis) limits the blood amount flowing through it, with reduced amount of oxygen supplied to the area by such a vessel. Because the oxygen requirement of the heart grows with increased body activity, situations that increase the activity of the heart, such as exercise or mental stress may induce this discrepancy between oxygen demand and supply and thus induce ischemia.