Diagnostic strategies for pulmonary embolism in patients hospitalized for COVID-19: Role of clinical prediction rules

ABSTRACT

Background: Diagnostic strategies for pulmonary embolism (PE) in patients already facing respiratory failure due to COVID-19 is challenging. The use of the conventional diagnostic algorithm and clinical prediction rules (CPR) for PE is controversial. Aim(s) To evaluate the accuracy of currently available diagnostic algorithms for the diagnosis of PE and CPRs to assess the risk for venous thromboembolism (VTE) in medically ill patients affected by COVID-19. Method(s) Consecutive patients >18 years hospitalized for COVID-19 (confirmed by molecular testing) at Perugia Hospital (Italy) from March 2020 to September 2021 were included if underwent chest- CT angiography for suspicion of PE. The study outcome was the accuracy of currently available CPRs, for PE diagnosis (Wells and Geneva) and for VTE-risk stratification in medically ill patients (IMPROVE, IMPROVEDD and Padua score), to predict PE. Result(s) 74 patients were included (mean age 68 years, male 64.9%), 13 (17.6%) had PE confirmed. No significant differences were observed for comorbidities, antithrombotic treatment and mortality between the two groups. D-dimer resulted significantly higher in patients with compared to patients without PE. Poor discrimination was observed for Wells and Geneva scores (AUC 0.596, 95% CI 0.413-0.779, and AUC 0.603, 95% CI 0.439-0.767, respectively), without substantial differences adding D-dimer at conventional cut-off (Table). The IMPROVEDD score had the highest discriminative power among CPRs for VTE (AUC 0.699, 95% CI 0.539-0.860). Scores' performance improved by increasing the D-dimer cut-off at level of 2000 ng/ml. Conclusion(s) The accuracy of the currently used diagnostic and predictive scores for PE or VTE in COVID-19 patients is poor. D-dimer improves the diagnostic accuracy of these scores;most of all, it seems to allow a diagnostic strategy with a high negative predictive value, so we can rule out a consistent part of the patients with a low risk of PE. (Table Presented).