Background: The frequency of emergency department pulmonary embolism (PE) testing is increasing, and CT pulmonary angiogram studies are commonplace. Neither YEARS nor age-adjusted PE testing have been prospectively evaluated in North America.
Aims: To assess the diagnostic accuracy of YEARS and age-adjusted algorithms in Canadian emergency departments.
Methods: This prospective diagnostic accuracy study was conducted in two tertiary care Canadian emergency departments, November 2019 to June 2021. Patients were included when they were tested for PE in the emergency department. We excluded repeat visits and cases without YEARS item documentation. Research ethics approved waiver of patient consent. The study was funded by PSI and SIDM.
Physicians used a standardized order set for PE testing whereby all patients had D-dimer testing (STA Liatest). If the D-dimer was < 500 ng/ml, PE was excluded. CT pulmonary angiography was performed when the D-dimer was ≥ 500 ng/ml. Patients were followed for 30 days by medical record review in every hospital in the city. PE was independently adjudicated. Physicians systematically recorded the presence or absence of YEARS items (PE most likely, hemoptysis, signs of deep vein thrombosis) prior to D-dimer or CT testing. We analyzed the diagnostic accuracy of YEARS and age-adjusted D-dimer (age-adjustment (age x 10) was applied in patients where PE was not the most likely diagnosis and 500 ng/ml threshold when PE was most likely).
Results: 1704 patients were included, median age 62 (50, 74), 58% female, PE prevalence 8.0%.
See Figure 1 for YEARS and Figure 2 for age-adjusted testing results. YEARS sensitivity was 92.6% (87.0, 96.0), specificity 45.0% (42.5, 47.5), NPV 98.6% (97.4, 99.2), PPV 12.6% (10.7, 14.9). Age-adjusted D-dimer sensitivity was 100.0% (97.2, 100.0), specificity 32.4% (30.1, 34.8), NPV 100.0% (99.2, 100.0), PPV 11.4% (9.7, 13.3).
Conclusion(s): YEARS was less sensitive and more specific than age-adjusted D-dimer for PE diagnosis.
To cite this abstract in AMA style:
de Wit K, Al-Haimus F, Hu Y, Ikesaka R, Chan N, Ibrahim Q, Klyn J, Clayton N, Germini F. Canadian prospective external validation of YEARS and age-adjusted pulmonary embolism testing [abstract]. https://abstracts.isth.org/abstract/canadian-prospective-external-validation-of-years-and-age-adjusted-pulmonary-embolism-testing/. Accessed November 30, 2023.« Back to ISTH 2022 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/canadian-prospective-external-validation-of-years-and-age-adjusted-pulmonary-embolism-testing/