Objective: To investigate whether D-dimer could be an early warning signal for patients with acute myocardial infarction (AMI), then may be helpful in risk assessment in emergency department.
Methods: Three thousand one hundred and thirty-four emergency AMI cases admitted to the hospital from January 1, 2009 to December 31, 2010 were retrospectively reviewed, and their age, gender, past medical history, D-dimer, MB isoenzyme of creatine kinase (CK-MB), cardiac troponin I (cTnI), the precursor of the N-terminal pro-brain natriuretic peptide (NT-proBNP), electrocardiogram (ECG) before treatment, and the CK-MB, cTnI and echocardiography left ventricular ejection fraction (LVEF) 2 hours after the treatment of percutaneous coronary intervention (PCI) or thrombolytic drugs, whether died and time from onset to death were recorded. According to the results of multivariate logistic regression analysis, draw the receiver operating characteristic curve (ROC curve) and fitting curve, and analyzed the relativity between the D-dimer before the treatment and prognosis of myocardial infarction.
Results: Multivariate logistic regression analysis showed that age [odds ratio (OR)=1.109, 95% confidence interval (95%CI) 1.073 to 1.147, P=0.000], whether undergoing emergency PCI (OR=4.162, 95%CI 1.980 to 8.748, P=0.000), D-dimer before treatment (OR=1.001, 95%CI 1.000 to 1.002, P=0.001), the LVEF values (OR=0.946, 95%CI 0.928 to 0.964, P=0.000) and cTnI after 2 hours of treatment (OR=1.011, 95%CI 1.004 to 1.018, P=0.002) were correlated to 28-day death. The ROC curves showed that age [area under curve (AUC) 0.796, P=0.000], whether undergoing emergency PCI (AUC 0.704, P=0.000), D-dimer before treatment (AUC 0.797, P=0.000) were positively correlated with the 28-day death; the LVEF values (AUC 0.261, P=0.000) were negative correlated with the 28-day death. The fitting curve of D-dimer before treatment, the time from onset to death and the LVEF showed no linear correlation.
Conclusions: D-dimer was correlated with the early prognosis of patients with myocardial infarction, but was not correlated with the time from onset to death. The rise in D-dimer at the early stage of AMI may be helpful to indicate the critical condition of the AMI patients.