A Comparative Analysis of the Impact of Severe Acute Respiratory Syndrome Coronavirus 2 Infection on the Performance of Clinical Decision-Making Algorithms for Pulmonary Embolism.

: This study aimed to compare the diagnostic accuracy of the Wells and Geneva scores using a 500 ng/mL D-dimer cutoff, as well as the age-adjusted D-dimer (AADD), YEARS, and pulmonary embolism graduated D-dimer (PEGeD) algorithms, in patients with and without COVID-19. Various D-dimer cutoffs were also evaluated. This retrospective study included emergency department patients who underwent computed tomography pulmonary angiography (CTPA) for suspected pulmonary embolism (PE). The diagnostic performances of clinical prediction algorithms were compared between COVID-19-positive and -negative groups. We analyzed data from 1423 patients; the PE and COVID-19 positivity rates were 7.3% and 69.9%, respectively. In COVID-19-positive patients, the Wells score with a 500 ng/mL D-dimer cutoff demonstrated 97.22% sensitivity (95% CI: 80.53-100.00) and 4.99% specificity (95% CI: 3.58-6.39). Using AADD raised the specificity to 7.81% (95% CI: 6.08-9.54) while maintaining 97.22% sensitivity (95% CI: 93.43-100.00); similar findings were observed with the Geneva score. The YEARS algorithm had 86.11% sensitivity (95% CI: 78.12-94.10) and 32.75% specificity (95% CI: 29.73-35.78), whereas the PEGeD algorithm showed 86.11% sensitivity (95% CI: 78.12-94.10) and 34.06% specificity (95% CI: 31.00-37.12). Both algorithms demonstrated slightly improved specificity and accuracy in COVID-19-positive patients. The YEARS and PEGeD algorithms showed slight improvements in specificity and accuracy among COVID-19-positive patients. The Wells and Geneva scores maintained higher sensitivity but lower specificity across groups. Adjusting the D-dimer cutoffs increased the specificity but increased the risk of missed diagnoses. Overall, COVID-19 had a minimal impact on PE diagnostic algorithm performances.