Secondary endpoints, determined by CMR within 3 to 5 days after PCI, included the infarct ratio (infarct size to entire left ventricular [LV] size ) by delayed-enhancement (DE), area at risk (AAR) ratio (AAR to LV size) by T2 high-signal intensity , microvascular occlusion index (MVO) ratio (MVO to LV size) by DE, and myocardial salvage index (MSI, [AAR-infarct size] x 100/AAR).