[The role of ischemic preconditioning in acute myocardial infarction].

Introduction: Ischemic preconditioning is a phenomenon in which brief episodes of ischemia and reperfusion increase myocardial tolerance and substantially reduce the infarction size.

Case Report: Two patients with acute left anterior descending artery occlusion received fibrinolytic therapy within 6 hours of symptom onset, but nevertheless developed myocardial infarctions of different size. The first patient, without a history of preinfarction angina, developed a large anterior infarction, because there was no time for ischemic preconditioning or development of coronary collateral vessels.