D-dimer as a Prognostic Tool in Patients with Normotensive Pulmonary Embolism

Abstract

Background: D-dimer testing is widely applied as a first step in the diagnostic work-up of pulmonary embolism (PE). Although this is the most sensitive assay for ruling out PE, the prognostic implications of D-dimer testing in patients with normotensive PE are not well known. The aim of this study was to determine if D-dimer testing on admission predicts major adverse cardiac events (MACE) in patients with normotensive PE. Methods: A total of 180 consecutive patients with normotensive PE admitted between January 2003 and June 2009 were included. The group was divided into quartiles on the basis of their D-dimer levels. We compared the frequency of MACE by quartile of D-dimer level and estimated sensitivity, specificity, and predictive values for MACE in the first and fourth quartile. Results: In the 37 (20.6%) patients with MACEs, the median D-dimer level (7.94 [IQR: 4.03∼18.17] μg/mL) was higher than in patients with a benign course (5.29 [IQR: 2.60∼11.52] μg/mL, p＜0.01). The occurrence of MACEs was increased with increasing D-dimer level (p=0.017). In the first quartile (D-Dimer ＜2.76 μg/mL) sensitivity, specificity, and positive and negative predictive values for predicting MACEs were, respectively, 91.9%, 29.4%, 25.2%, and 93.3%. Conclusion: Patients with D-dimer levels below 2.76 μ g/mL have a low risk of MACEs. Our study suggest that D-dimer level may be used to identify low risk patients with normotensive PE.