Stand-alone D-dimer testing to rule out acute pulmonary embolism.
J Thromb Haemost. 2016 Nov 22;:
Authors: van Es N, van der Hulle T, Büller H, Klok FA, Huisman MV, Galipienzo J, Di Nisio M
BACKGROUND: Recently, stand-alone D-dimer testing at a positivity threshold of 750 μg/L has been proposed as a safe and efficient approach to rule out acute pulmonary embolism (PE), without additional imaging, but this approach needs validation.
OBJECTIVES: To evaluate stand-alone D-dimer testing at a positivity threshold of 750 μg/L to rule out PE.
METHODS: Individual data from 7,268 patients with suspected PE previously enrolled in 6 prospective management studies were used. Patients were assessed by the Wells rule followed by quantitative D-dimer testing in those with a PE unlikely score. Patients were classified post-hoc as having a negative (<750 μg/L) or positive (≥750 μg/L) D-dimer. Using a one-stage meta-analytic approach, the negative predictive value (NPV) of stand-alone D-dimer testing was evaluated overall and in different risk subgroups.
RESULTS: The pooled PE prevalence was 23% (range: 13-42%). Overall, 44% of patients had a D-dimer <750 μg/L of whom 2.8% were diagnosed with PE at baseline or during 3-month follow-up (NPV 97.2%; 95%-CI 94.9-98.5). The NPV was highest in patients with a low probability of PE according to the Wells rule (99.2%, 95%-CI 98.6-99.5%) and lowest in those with a high probability of PE (79.3%, 95% CI 53.0-92.8%). The NPVs in patients with active cancer, previous venous thromboembolism, and inpatients were 96.2% (95%-CI 85.6-99.1%), 94.7% (95%-CI 88.6-97.6%), and 92.7% (95%-CI 79.3-97.7%), respectively.
CONCLUSIONS: Our findings suggest that stand-alone D-dimer testing at a positivity threshold of 750 μg/L is not safe to rule out acute PE. This article is protected by copyright. All rights reserved.
PMID: 27873439 [PubMed - as supplied by publisher]