Abstract Number: PB2274
Meeting: ISTH 2020 Congress
Theme: Venous Thromboembolism and Cardioembolism » VTE Diagnosis
Background: In the ambulatory setting, several well-validated prediction tools exist to risk stratify patients with suspected pulmonary embolism (PE). This allows for more appropriate use of diagnostic computed tomography pulmonary angiography (CTPA), in order to address the issue of overuse and over-diagnosis. There is sparse evidence for the application of these tools among inpatients. As such, we hypothesized a lower diagnostic yield of CTPA in this group.
Aims: To determine the diagnostic yield of CTPA for PE in ambulatory patients compared to inpatients in a Canadian tertiary care center. Secondary outcomes include the incidence of: Wells score, D-dimer and appropriate CTPA use; and the comparative predictive value of the Wells score and D-dimer at our institution.
Methods: We performed a retrospective cohort study of all patients who underwent CTPA at the Jewish General Hospital in Montreal, Canada between January 1st and June 30th 2013. Patient demographics, presenting symptoms, and explicit use of the Wells score and D-dimers were collected. Post-hoc Wells scores were generated from available clinical data for all patients to estimate their pre-CTPA risk categorization.
Results: A total of 464 emergency department (ED) patients and 192 inpatients underwent CTPA during the study period. The yield was similar between populations (14.1% vs. 14.4%, p=0.9). There were twice as many subsegmental PEs amongst inpatients (33.3% vs. 14.9%, p=0.044). Only 3.2% of cohort patients had a Wells score recorded. Patients with a generated Wells low probability score were significantly less likely to have a positive CTPA (7.7% vs. 17.4%, p< 0.001). No patients in our cohort with a negative D-dimer had a positive CTPA.
Conclusions: The yield of CTPA is similar in the inpatient and ED populations. This may be partially explained by the suboptimal implementation of pretest probability algorithms and D-dimer use in the ED. Further work is needed to elaborate their role amongst inpatients.
To cite this abstract in AMA style:
Gerstein L, Koolian M, Schwartz B. A Practical Comparison of a PE Diagnostic Approach: Is All Wells in the World? [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/a-practical-comparison-of-a-pe-diagnostic-approach-is-all-wells-in-the-world/. Accessed October 2, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/a-practical-comparison-of-a-pe-diagnostic-approach-is-all-wells-in-the-world/