Reperfusion injury in acute myocardial infarction

Since the early 1970s, infarct size has been identified as a major predictor of prognosis after myocardial infarction: infarct size parallels with arrhythmia, heart failure, and mortality [ 1 ]. Apart from this finding, infarct size is not only determined by the area at risk; that is, the myocardium perfused by the infarct-related artery. In a seminal work, Reimer and coworkers could show that irreversible myocardial injury, as determined by cardiac myocyte necrosis, progresses as a wavefront from the subendocardium towards the subepicardium [ 2 ]. This observation led to the concept that early reperfusion therapy can salvage myocardium at risk from injury. Early reperfusion therapy within the first 3 to 6 hours after the onset of ischemia was, in consequence, rapidly introduced into clinical routine and is now standard treatment of patients with acute myocardial infarction.