Pre-conditioning and postconditioning to limit ischemia-reperfusion-induced myocardial injury: what could be the next footstep?

Myocardial ischemia is a condition in which the coronary blood flow to the heart is reduced, which results in deficient oxygen and nutrients supply to the heart. Reperfusion to an ischemic myocardium often results in lethal myocardial injury. The brief episodes of ischemia and reperfusion given before prolonged ischemia and reperfusion denote pre-conditioning. On the other hand, brief episodes of ischemia and reperfusion given after prolonged ischemia and at the onset of reperfusion denotes postconditioning. Pre- and postconditioning are anti-jeopardized phenomenons in which both forms have been shown to protect the myocardium from lethal ischemia-reperfusion injury. However, numerous experimental studies reveal that the cardioprotective effects of these phenomenons have been suppressed in presence of some pathological factors such as hyperglycemia, obesity, hypercholesterolemia, etc. In this review, we have critically discussed the mechanisms involved in the cardioprotective effects of pre- and postconditioning to limit ischemia-reperfusion-induced myocardial injury. Moreover, the clinical relevance and factors affecting the cardioprotective potentials of pre- and postconditioning have been delineated.