Usefulness of D-dimer as a Predictor of High-risk Patients for Early Invasive Treatment and Early Death in Non-ST Elevation Acute Coronary Syndrome Patients

ABSTRACT

PURPOSE: The aim of the study is to evaluate the efficacy of initial plasma D-dimer levels measured in the emergency department (ED) in prediction of early 28-day mortality and high-risk patients for early invasive treatment in patients with Non-ST elevation acute coronary syndrome (NST-ACS). METHODS: This is a retrospective clinical study of NST-ACS patients in the ED. All patients were managed according to the 2010 ACLS guidelines. EKG, cardiac markers, and D-dimer were analyzed. All data were collected via electronic medical records. The two major endpoints were 28-day mortality and high-risk patients who were defined as cases with one of the following refractory ischemic chest discomfort, recurrent/persistent ST deviation, ventricular tachycardia, hemodynamic instability, and signs of heart failure. We assessed the relationship between initial D-dimer levels, and high-risk patients, and 28-day mortality. RESULTS: A total of 390 patients were analyzed. There were 25 high-risk patients (6.41%) and 10 non-survival cases (2.56%). The median (inter-quartile ranges) D-dimer value was higher in high-risk patients than in non-high risk patients (1.36 [0.57 to 2.30] vs. 0.31 [0.23 to 0.53] ug/dL; p<0.0001). Area under curve (AUC) in Receiver-operatory characteristic (ROC) curve for D-dimer in high-risk patients was 0.834 (95% confidence interval 0.750-0.920) with the optimum cutoff value of 0.475ug/dL with a sensitivity of 84% and a specificity of 71%. The median value of D-dimer in non-survival cases was higher than in survival cases (1.17 [0.84 to 18.46] vs. 0.33 [0.23 to 0.56] ug/dL; p<0.0001). AUC for D-dimer in predicting 28-day mortality was 0.837 (95% CI 0.710-0.964) with the optimum cutoff value of 0.98 ug/dL with a sensitivity of 80.0% and a specificity of 86.3%. CONCLUSION: The D-dimer level in the initial state might be helpful in predicting high-risk patients for early invasive treatment or 28-day mortality in patients with NST-ACS in the ED.