 Comparison of the different therapies in randomized trials shows an advantage of primary PCI regarding rates of recanalisation of the infarct vessel, preservation of left ventricular LV function, and reduction in the rate of reinfarctions. In addition, the in-hospital mortality is lower in patients undergoing primary PCI. Nevertheless, primary PCI does not always result in a successful reperfusion despite of successful restoration of blood flow in the epicardial infarct related artery. 