Study investigates D-dimer testing in patients at higher risk of pulmonary embolism

A new study investigating D-dimer testing in patients who are at higher risk of pulmonary embolism (PE) has been published in the February issue of Academic Emergency Medicine (AEM), the peer-reviewed journal of the Society for Academic Emergency Medicine (SAEM).

The study, titled Failure rate of D-dimer testing in patients with high clinical probability of pulmonary embolism: Ancillary analysis of three European studies, evaluates the safety of ruling out PE based on D-dimer testing among patients who present a high clinical probability of the condition.

Pulmonary embolism is commonly suspected in emergency departments (EDs) and is a potentially life-threatening condition. Accurate diagnosis is critical for ensuring effective management and treatment. For patients who are at a low or moderate risk for PE, a diagnostic strategy based on D-dimer levels is advised due to its high negative predictive value. In patients with a high clinical probability of PE, the high prevalence may reduce the negative predictive value of D-dimer testing and increase the risk of diagnostic failure. Therefore, guidelines recommend that these high-risk patients undergo chest imaging (CI) without D-dimer testing, although very little evidence supports this approach.

The study aims to address the uncertainty surrounding the safety of excluding PE based on D-dimer levels in high-risk patients. Lead author Héloïse Bannelier, MD, and colleagues conducted a post hoc analysis of three European studies (PROPER, MODIGLIANI, and TRYSPEED). Patients included in the analysis had a high clinical probability of PE, according to either the Wells or the revised Geneva score, and had undergone D-dimer testing.

The findings indicated that ruling out PE based on a D-dimer level below the age-adjusted threshold was safe, with no missed cases of pulmonary embolism. However, the study's sample size was not large enough to draw a definitive conclusion on the safety of this diagnostic strategy. The results of this study may have important implications for the clinical management of high-risk PE patients. Further research is necessary to validate these findings in larger populations.