ObjectiveTo evaluate the effects of tirofiban on no-reflow phenomenon in patients with acute myocardial infarction (AMI) receiving emergency percutaneous coronary intervention (PCI). MethodsFrom January 2006 to December 2008,104 AMI patients were divided into tirofiban treatment and control groups (n=48 and 56,respectively) according to whether tirofiban was applied during emergency PCI. The patients’ basic clinical characteristics,angiographic results,and PCI efficiency were compared between two groups. Thrombolysis in Myocardial Infarction study (TIMI) grading and TIMI frame count (TFC) were performed in all culprit vessels after emergency PCI. ResultsThere was no significant difference between two groups in basic clinical characteristics and preoperative angiogram. Compared with control group,better TIMI 3 blood flow (91.7 % vs 76.8 %,P = 0.0408),less no-reflow rate (4.2% vs 16.1 %,P=0.0491),less distal embolization rate (8.3 % vs.23.2 %,P =0.0408) and better TFC (20.2±2.8 vs 31.2±4.4,P=0.0225) were achieved in tirofiban treatment group. No severe bleeding complication occurred in any patients. Major adverse cardiac events were significantly higher in control group than in tirofiban treatment group (12.5% vs 8.9%,P=0.011). ConclusionTirofiban used during emergency PCI in patients with AMI can effectively prevent no-reflow phenomenon.