Abstract: AIM: To study the effect and clinical significance of tirofiban on serum matrix metalloproteinase 9(MMP-9) and after primary percutaneous coronary intervention(PCI) in patients with acute ST-segment elevation myocardial infarction (STEMI)and diabetes.METHODS: One hundred and twenty-three patients with acute STEMI and diabetes who were treated with primary PCI were designed into two groups: routine treatment group(61 cases) and tirofiban group(62cases).The clinical datas and coronary arterydisorders datas in two groups were compared.The serum MMP-9 levels among two groups before and after primary PCI were detected, as well as the incidences of in-stent restenosis(ISR) at 12 months after primary PCI.RESULTS: The clinical datas,the degreee of coronary stenosis and the number of lesion vessels were similar between the two groups(P>0.05). The levels of MMP-9 in the two groups were both significantly higher after PCI(P<0.05).The level of MMP-9 after PCI from the tirofiban group was obviously lower than that in the routine treatment group(P<0.05).The incidence of in-stent restenosis(ISR) from the tirofiban group was distinctly lower than that in the routine treatment group(P<0.05).CONCLUSION: The level of serum MMP-9 is higher after the primary PCI in patients with acute STEMI and diabetes.The tirofiban can reduce the incidence of post-stenting restenosis by the means of degrading the level of MMP-9.

Key words: Tirofiban, Myocardial infarction, Diabetes, Primary percutaneous coronary intervention, Matrix metalloproteinase-9