Rapid quantitative D-dimer to exclude pulmonary embolism: a prospective cohort management study

Area of Science:

• Medical Diagnostics
• Clinical Pathology
• Cardiovascular Medicine

Background:

• Pulmonary embolism (PE) diagnosis often requires imaging, leading to delays and costs.
• Clinical probability assessment combined with D-dimer testing can exclude PE but may be complex.
• Efficient strategies are needed to rule out PE without imaging.

Purpose of the Study:

• To evaluate the safety and efficacy of using D-dimer testing alone to exclude PE.
• To determine if a negative D-dimer result can reliably rule out PE without clinical probability assessment.

Main Methods:

• 808 outpatients and inpatients with suspected PE were enrolled.
• A quantitative latex agglutination D-dimer assay was used for testing.
• Patients with negative D-dimer (<750 μg FEU/L) were not imaged and followed for 3 months.

Main Results:

• 52% of patients had a negative D-dimer and did not receive anticoagulants.
• Only one patient (out of 420 with negative D-dimer) experienced venous thromboembolism (VTE) during follow-up.
• The negative predictive value of D-dimer testing alone for PE was 99.8%.

Conclusions:

• A negative quantitative latex agglutination D-dimer assay reliably excludes PE as a standalone diagnostic test.
• This approach simplifies PE diagnosis, potentially reducing the need for imaging in about half of suspected cases.