Acute pulmonary embolism in patients presenting pulmonary deterioration after hospitalisation for non-critical COVID-19

Background Emerging evidence suggests an association between COVID-19 and acute pulmonary embolism (APE). Aims To assess the prevalence of APE in patients hospitalised for non-critical COVID-19 who presented clinical deterioration, and to investigate the association of clinical and biochemical variables with a confirmed diagnosis of APE in these subjects. Methods All consecutive patients admitted to the internal medicine department of a general hospital with a diagnosis of non-critical COVID-19, who performed a computer tomography pulmonary angiography (CTPA) for respiratory deterioration in April 2020, were included in this retrospective cohort study. Results Study populations: 41 subjects, median (interquartile range) age: 71.7 (63-76) years, CPTA confirmed APE = 8 (19.51%, 95% confidence interval (CI): 8.82-34.87%). Among patients with and without APE, no significant differences were found with regards symptoms, comorbidities, treatment, Wells score and outcomes. The optimal cut-off value of d-dimer for predicting APE was 2454 ng/mL, sensitivity (95% CI): 63 (24-91), specificity: 73 (54-87), positive predictive value: 36 (13-65), negative predictive value: 89 (71-98) and AUC: 0.62 (0.38-0.85). The standard and age-adjusted d-dimer cut-offs, and the Wells score >= 2 did not associate with confirmed APE, albeit a cut-off value of d-dimer = 2454 ng/mL showed an relative risk: 3.21; 95% CI: 0.92-13.97; P = 0.073. Heparin at anticoagulant doses was used in 70.73% of patients before performing CTPA. Conclusion Among patients presenting pulmonary deterioration after hospitalisation for non-critical COVID-19, the prevalence of APE is high. Traditional diagnostic tools to identify high APE pre-test probability patients do not seem to be clinically useful. These results support the use of a high index of suspicion for performing CTPA to exclude or confirm APE as the most appropriate diagnostic approach in this clinical setting.