Highly Elevated Quantitative D-Dimer Assay Values Increase the Likelihood of Venous Thromboembolism

Area of Science:

• Medical Diagnostics
• Hematology
• Emergency Medicine

Background:

• D-dimer assay is a common diagnostic tool for suspected venous thromboembolism (VTE).
• The assay helps determine the need for further radiographic imaging in VTE workup.
• Previous studies suggest a correlation between D-dimer levels and VTE likelihood.

Purpose of the Study:

• To compare D-dimer levels in patients with suspected VTE.
• To test the hypothesis that higher D-dimer values predict a higher likelihood of VTE diagnosis.

Main Methods:

• Secondary analysis of a multinational, prospective observational study.
• Included low- to intermediate-risk adult patients presenting to the emergency department with VTE suspicion.
• D-dimer values were analyzed using logistic regression, with advanced imaging at physician discretion.

Main Results:

• 1,752 patients evaluated for DVT (10.4% positive); 1,834 for PE (5.9% positive).
• Higher D-dimer values correlated with increased likelihood of VTE diagnosis in both groups.
• D-dimer values >3,999 ng/mL showed the highest VTE incidence, with over 50% positivity.

Conclusions:

• Elevated D-dimer levels predict an increased likelihood of VTE diagnosis.
• In the highest D-dimer category (>3,999 ng/mL), more than half of patients were diagnosed with VTE.
• Further research may refine D-dimer's role in VTE workup.