Introduction: The focus of this research was to explore the link between CRP (C-reactive protein) /albumin ratio (CAR), a novel inflammatory response marker, and no-reflow (NR) phenomena in non-ST elevation myocardial infarction (non-STEMI) patients during percutaneous coronary intervention (PCI). The gene discussed is CRP; the disease is ST Elevation Myocardial Infarction.