What level of D-dimers can safely exclude pulmonary embolism in COVID-19 patients presenting to the emergency department?

Marie-Pierre Revel; Nathanael Beeker; Raphael Porcher; Léa Jilet; Laure Fournier; Bastien Rance; Guillaume Chassagnon; Michaela Fontenay; Olivier Sanchez; AP-HP /Universities/Inserm COVID-19 research collaboration, AP-HP Covid CDR Initiative

doi:10.1007/s00330-021-08377-9

What level of D-dimers can safely exclude pulmonary embolism in COVID-19 patients presenting to the emergency department?

Eur Radiol. 2022 Apr;32(4):2704-2712. doi: 10.1007/s00330-021-08377-9. Epub 2022 Jan 7.

Authors

Marie-Pierre Revel^{1

2}, Nathanael Beeker^{3

4}, Raphael Porcher^{3

5}, Léa Jilet⁴, Laure Fournier^{3

6}, Bastien Rance^{3

7}, Guillaume Chassagnon^{3

8}, Michaela Fontenay^{3

9

10}, Olivier Sanchez^{3

11

12}; AP-HP /Universities/Inserm COVID-19 research collaboration, AP-HP Covid CDR Initiative

Affiliations

¹ Université de Paris, 75006, Paris, France. marie-pierre.revel@aphp.fr.
² Radiology Department, Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Cochin, Service de Radiologie27 rue du Faubourg Saint Jacques, 75014, Paris, France. marie-pierre.revel@aphp.fr.
³ Université de Paris, 75006, Paris, France.
⁴ Assistance Publique-Hôpitaux de Paris (AP-HP), Unité de Recherche Clinique, Hôpital Cochin, Paris, France.
⁵ Assistance Publique-Hôpitaux de Paris (AP-HP), Centre d'épidémiologie clinique, Hôtel-Dieu, Paris, France.
⁶ Assistance Publique-Hôpitaux de Paris (AP-HP), Service de Radiologie, Hôpital Européen, Georges Pompidou, Paris, France.
⁷ Assistance Publique-Hôpitaux de Paris (AP-HP), Département d'Informatique Médicale, Biostatistiques Et Santé Publique, Hôpital Européen Georges Pompidou, Paris, France.
⁸ Radiology Department, Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Cochin, Service de Radiologie27 rue du Faubourg Saint Jacques, 75014, Paris, France.
⁹ Assistance Publique-Hôpitaux de Paris (AP-HP), Service de d'hématologie biologique, Hôpital Cochin, Paris, France.
¹⁰ Institut Cochin INSERM U1016, CNRS UMR8104, Paris, France.
¹¹ Assistance Publique-Hôpitaux de Paris (AP-HP), Service de Pneumologie Et Soins Intensifs, Hôpital Européen, Georges Pompidou, INSERM UMRS-1140 Innovative Therapies in Hemostasis and Biosurgical Research Lab (Carpentier Foundation), Paris, France.
¹² F-CRIN INNOVTE, Saint-Etienne, France.

Abstract

Objectives: To identify which level of D-dimer would allow the safe exclusion of pulmonary embolism (PE) in COVID-19 patients presenting to the emergency department (ED).

Methods: This retrospective study was conducted on the COVID database of Assistance Publique - Hôpitaux de Paris (AP-HP). COVID-19 patients who presented at the ED of AP-HP hospitals between March 1 and May 15, 2020, and had CTPA following D-dimer dosage within 48h of presentation were included. The D-dimer sensitivity, specificity, and positive and negative predictive values were calculated for different D-dimer thresholds, as well as the false-negative and failure rates, and the number of CTPAs potentially avoided.

Results: A total of 781 patients (mean age 62.0 years, 53.8% men) with positive RT-PCR for SARS-Cov-2 were included and 60 of them (7.7%) had CTPA-confirmed PE. Their median D-dimer level was significantly higher than that of patients without PE (4,013 vs 1,198 ng·mL^-1, p < 0.001). Using 500 ng·mL^-1, or an age-adjusted cut-off for patients > 50 years, the sensitivity and the NPV were above 90%. With these thresholds, 17.1% and 31.5% of CTPAs could have been avoided, respectively. Four of the 178 patients who had a D-dimer below the age-adjusted cutoff had PE, leading to an acceptable failure rate of 2.2%. Using higher D-dimer cut-offs could have avoided more CTPAs, but would have lowered the sensitivity and increased the failure rate.

Conclusion: The same D-Dimer thresholds as those validated in non-COVID outpatients should be used to safely rule out PE.

Key points: • The median D-dimer level was significantly higher in COVID-19 patients with PE as compared to those without PE (4,013 ng·mL^-1 vs 1,198 ng·mL^-1 respectively, p < 0.001). • Using 500 ng·mL^-1, or an age-adjusted D-dimer cut-off to exclude pulmonary embolism, the sensitivity and negative predictive value were above 90%. • Higher cut-offs would lead to a reduction in the sensitivity below 85% and an increase in the failure rate, especially for patients under 50 years.

Keywords: Angiography, computed tomography; COVID-19 pandemic; Diagnostic technics and procedures; Pulmonary embolism; Pulmonary thromboembolism.

MeSH terms

COVID-19*
Emergency Service, Hospital
Female
Fibrin Fibrinogen Degradation Products
Humans
Male
Middle Aged
Pulmonary Embolism*
Retrospective Studies
SARS-CoV-2

Substances

Fibrin Fibrinogen Degradation Products
fibrin fragment D