Correlation Between D-dimer And Severity Of Coronary Artery Disease And Long-term Prognosis In Patients With ST-segment Elevation Myocardial Infarction

Objective: To Study and evaluate the correlation between D-dimer levels and severity of coronary artery disease as well as the long-term prognosis in patients with ST-segment elevation myocardial infarction.Methods:We consecutively enrolled 440 STEMI patients who were admitted to the heart center of the First Affiliated Hospital of Xinjiang Medical University with complete information from October 2014 to February2017.Blood samples were taken immediately before Percutaneous Coronary Intervention(PCI)at the time of admission to determine plasma D-dimer levels.Patients were divided into three groups according to the D-dimer levels as follows: high D-D group(>366 μg/L,n=152,male 108 female 44)and middle D-D group(145-366 μg/L,n=143,male 107 female 36),low D-D group(<145 μg/L,n=145,male 112 female 33).These patients were followed up for two years.Major adverse cardiovascular and cerebrovascular events(MACCE)were deftned as the occurrence of death.myocardial infarction,target vessel revascularization,intra stent thrombosis and stroke during follow-up.We calculated the lesion count and Gensini score based on coronary angiography and made analysis and comparison of the correlation between D-dimer levels and severity of coronary vascular disease in three groups.Multivariate Cox regression analysis was used to study the independent influencing factors in STEMI patients endergoing emergency PCI.Results:The Gensini score in the high D-D group(99±23)was significantly higher than that in the middle(52±22)and low D-D group(25 ± 16),the difference was statistically significant(P <0.01).Patients in high D-D group had significantly higher morality in the hospital rather than in the low D-D group.D-dimer levels in elderly STEMI patients were correlated with severity of coronaryvascular disease(r=0.668,P<0.01).Combined with post-discharged follow-up results,patients with high D-D had major adverse cardiac events(MACE),and stroke and death were higher than the other two groups(P<0.01).However,there was no significant difference in relapsed events of myocardial infarction,target vessel revascularization between the three groups.Multivariate Cox regression analysis showed that D-dimer is an independent risk factor for 2-year cardiac death(HR=1.232,95%CI 1.030~1.454,P=0.021),and also it is a risk factor for MACCE(HR=0.94,95%CI 0.89~0.98,P=0.002).Conclusion:The level of plasma D-dimer in STEMI patients is positively correlated with the degree of coronary artery disease,which can reflect the severity of the disease.It is instructive for risk stratification and early identification of high-risk patients.D-dimer is also associated with the long-term prognosis in STEMI patients.High D-dimer is an independent risk factor for long-term mortality of STEMI patients after emergency PCI.