Cyclosporine A Prior to Primary PCI in STEMI Patients: The Coup de Grâce to Post-Conditioning?

O ne major predictor of morbidity andmortality after a myocardial infarction is infarct size (IS). Early revascularization, with the aim of re-establishing coronary flow, is indeed the best available treatment, provided that it is implemented early enough after coronary artery occlusion. However, in the process of myocardial salvage via reperfusion, the heart is also subjected to reperfusion injury (RI), whose unfavorable manifestations include both transient (myocardial stunning, arrhythmias) and irreversible components (microvascular obstruction and lethal RI) (1). More specifically, lethal RI occurs when cells reversibly damaged by an ischemic insult are induced to die by the subsequent reperfusion. The technical inability to assess the relative injurious consequences of ischemia and reperfusion in the same biological sample has led to skepticism in many cardiologists, who for several years have underestimated, or even refused to believe in the existence of RI. This controversy is not merely academic, but has important clinical consequences because it implies that reperfusion itself triggers injurious events, independent from those occurring during the preceding ischemic period, which can be attenuated, or even prevented, by specific interventions delivered only at the time of reperfusion. The dispute seemed to be settled in favor of the “believers” with the seminal discovery of