Myocardial Preconditioning: From a Model to a Phenomenon

Originally, the term ischemic preconditioning described the observation that four 5 minute episodes of coronary artery occlusion in dogs followed by prolonged ischemia (40 minutes) and reperfusion resulted in a marked reduction in the rate of ATP depletion and limitation of myocardial infarction (1). Sustained ischemia alone produces about 30% myocardial infarction of the area at risk. These observations have been reproduced in small and large animal models of coronary artery occlusion and reperfusion whereby a single episode (or multiple episodes) of ischemia and reperfusion protected the myocardium against infarction, but failed to augment recovery of ventricular function in the same model.