Remote cardiac ischemic conditioning: underlying mechanisms and clinical applications.

Despite a significant improvement in the care of acute coronary disease, mortality and morbidity remain important. One explanation for this lies in the fact that the very coronary reperfusion may paradoxically result in additional myocardial injury, through the so-called ischemia-reperfusion injury, partially mitigating the beneficial effects of myocardial reperfusion. Over the past two decades, numerous pharmacological interventions (such as the use of antioxidants, anti-inflammatory, magnesium, glucose/insulin/potassium, rapid normalization of pH) were studied in order to prevent ischemia-reperfusion injury. Despite the promising results obtained in animal experiments, attempts to transpose these results to humans, and consequently to clinical practice, have been disappointing. On the other hand, cardiac ischemic conditioning is an intervention that has produced positive results. Ischemic conditioning refers to the protection induced by short periods of ischemia followed by reperfusion, prior to a major ischemic event. Ischemic stimulus can be applied before (pre-conditioning), during (per-conditioning) or after (post-conditioning) the major ischemic event. An important finding regarding cardiac ischemic conditioning, was that protection could be induced remotely, introducing the concept of remote ischemic conditioning. In this paper, we proposed to review the mechanisms underlying remote ischemic cardiac conditioning and the possible clinical applications, considering more specifically pre and per-conditioning.