Cardiac preconditioning. Induction of endogenous tolerance to ischemia-reperfusion injury.

Cardiac preconditioning is a phenomenon by which a brief exposure to ischemia renders the heart more tolerant of a subsequent sustained ischemic insult. Understanding the mechanism involved may allow pharmacologic access to this protective state before cardiopulmonary bypass surgery and transplantation. We discuss herein the preconditioning phenomenon, the potential mechanisms involved, and the therapeutic implications of cardiac preconditioning.