Description of the clinical and radiological characteristics of pulmonary embolism in COVID-19 vs non–COVID-19 patients: a multicentric cross-sectional study over a 24-month perspective

Background: COVID-19 is associated with intense systemic inflammation and abnormal coagulation profile, leading to an increased incidence of pulmonary embolism (PE). Objectives: This study investigates whether PE in COVID-19 patients has different clinical, laboratory, and radiological characteristics compared with traditional PE in COVID-19–negative patients. Methods: We conducted an observational, multicentric, cross-sectional study on consecutive patients diagnosed with PE at admission or during hospital stay from February 21, 2019, to February 20, 2021. We compared clinical and laboratory data and computed tomography images between COVID-19–positive and COVID-19–negative patients. The extent of PE was evaluated using the Qanadli Index. Results: Among 771 enrolled patients with acute PE, 89 were COVID-19–positive. COVID-19 patients were predominantly male (59.6% vs 41.5%, P = .001) and exhibited fewer classic venous thromboembolism (VTE) risk factors, such as previous VTE (3.5% vs 11.5%, P = .02) and active cancer (4.7% vs 24.2%, P < .0001). Additionally, these patients showed lower median troponin T and pro-B-type-natriuretic-peptide levels (10 vs 32 ng/L, P = .0002; and 383 vs 1448 pg/mL, P = .004, respectively), a lower median Qanadli Index (4 vs 7, P = .0013), more distal PE obstructions (53.5% vs 32.9%, P < .001), and less frequent right ventricular dilatation (4.1% vs 10.9%, P = .09). Conclusion: In COVID-19 patients, traditional VTE risk factors were less frequent, a possible role for in situ thrombo-inflammatory processes. The reduced radiological extent and severity of PE observed in COVID-19 patients may reflect an in situ thrombo-inflammatory process rather than classical embolization; however, this hypothesis needs to be confirmed by other studies.