Objective To investigate the correlation between serum monoamine oxidase(MAO),soluble growth stimulation expressed gene 2(sST2)and coronary slow flow(CSF),and to evaluate their value in pre-dicting CSF risk and guiding clinical decision-making.Methods A total of 118 patients with CSF confirmed by coronary angiography from January 2022 to September Dazhu Hospital Affiliated to North Sichuan Medical College 2023 were selected as the observation group,while 120 patients with normal coronary blood flow were selected as the control group.The coronary flow velocity was assessed using the TIMI frame count(TFC).Baseline characteristics,as well as serum MAO and sST2 levels,were compared between the two groups.Multi model calibration Logistic regression analysis was used to examine the relationship between the two markers and CSF.Pearson correlation analysis was conducted to evaluate the association between the markers and TFC.The predictive efficacy of MAO and sST2 for CSF and their benefit in clinical decision-making were as-sessed using receiver operating characteristic(ROC)curve and decision curve analysis(DCA).Results(1)The levels of body mass index(BMI),smoking proportion,C-reactive protein(CRP),uric acid(UA),creati-nine(Cr),MAO,and sST2 in the observation group were all higher than those in the control group(P＜0.05).(2)The TFC and mean TFC of LAD,LCX,and RCA in the observation group were higher than those in the control group(P＜0.05).(3)Multivariate Logistic regression analysis suggested that serum MAO and sST2 were independent risk factors for the occurrence of CSF(OR＞1,P＜0.05).(4)Pearson correlation a-nalysis showed that serum MAO and sST2 levels were positively correlated with the TFC of the LAD,LCX,and RCA,as well as the mean TFC(r=0.735,0.710,0.728,0.703,r=0.727,0.669,0.684,0.705,P＜0.05).(5)ROC curve revealed that the area under the curve(AUC)for predicting CSF was 0.761 of MAO,0.750 of sST2,and 0.807 of their combination.(6)DCA curve showed that the net benefit of serum MAO was greater than 0 when the threshold probability was between 0.05 and 0.70,the net benefit of serum sST2 was greater than 0 when the threshold probability was between 0.05 and 0.85,and their combined prediction yielded a greater net benefit within the threshold range of 0.40 to 0.90.Conclusion Elevated serum MAO and sST2 levels are independent risk factors for CSF.Both markers have good predictive value for CSF,and their combined detec-tion further improves predictive performance and clinical net benefit.

Objective To explore the association between extracellular matrix metalloproteinase inducer(EMMPRIN) and urokinase-type plasminogen activator (uPA) and the severity of coronary artery lesions in coronary heart disease (CHD) patients.Methods This study enrolled 88 patients with acute coronary syndrome (ACS) and 46 patients with stable angina pectoris (SAP).The mean fluorescence intensity (MFI) of EMMPRIN on monocytes of peripheral blood (PBMCs) were examined by flow cytometry.uPA in serum was measured with ELISA.64-slice spiral computed tomography coronary artery imaging was performed in 108 CHD patients.Coronary artery plaques were divided into type Ⅰ (33 patients),type Ⅱ (59 patients) and type Ⅲ (44 patients) through plaque morphology characteristics according to coronary angiography.Coronary artery plaques were divided into soft (42 patients),fibrous (34 patients) and calcified plaque (32 patients) according to CT characteristics.Results (1)Type Ⅱ plaque(48 patients)and soft plaque (35 patients) were the major plaque types in the ACS patients,while type Ⅰ plaque (20 patients) and type Ⅲ plaque (17 patients) and fibrous plaque (16 patients) and calcified plaque (22 patients)were the major plaque types in the SAP patients.(2)The EMMPRIN expression and uPA levels were significantly higher in type Ⅱ plaque group (EMMPRIN MFI:1 1.61 ± 0.81,uPA:(0.89 ± 0.17) mg/L) than those in the type Ⅰ plaque group (EMMPRIN MFI:6.65 ± 1.32,uPA:(0.53 ±0.06) mg/L) and in the type Ⅲ plaque group (EMMPRIN MFI:9.47 ± 1.16,uPA:(0.56 ±0.04) mg/L,all P ＜ 0.05).The EMMPRIN expression was higher in the type Ⅲ plaque group (MFI:9.47± 1.16)than in the type Ⅰ plaque group (MFI:6.65 ± 1.32,P ＜ 0.05),but uPA levels were similar between the 2 groups ((0.56 ± 0.04) mg/L vs.(0.53 ± 0.06) mg/L).(3) The EMMPRIN expression and uPA levels in the soft plaque group (EMMPRIN MFI:11.37 ± 0.76,uPA:(0.97 ± 0.12) mg/L) were significantly higher than those in the fibrous plaque group (EMMPRIN MFI:8.93 ± 1.21),uPA:(0.52 ±0.09) mg/L) and calcified plaque group (EMMPRIN MFI:6.94 ± 1.19,uPA:(0.49 ± 0.12) mg/L,P ＜0.05).The EMMPRIN expression in the fibrous plaque group(MFI:8.93 ± 1.21) was higher than in the calcified plaque group (MFI:6.94 ± 1.19,P ＜ 0.05),but uPA levels were similar between the two groups.Conclusion Higher EMMPRIN expression and uPA levels were associated with plaque instability,which might be used to evaluate plaque stability in CHD patients.