Pulmonary embolism severity and in-hospital mortality: An international comparative study between COVID-19 and non-COVID patients.

Objective: To compare the severity of pulmonary embolism (PE) between patients with and without COVID, and to assess the association between severity and in-hospital-mortality.

Methods: We performed an analysis of 549 COVID (71.3% PCR-confirmed) and 439 non-COVID patients with PE consecutively included by 62 Spanish and 16 French emergency departments. PE-severity was assessed by size, the presence of right ventricular dysfunction (RVD), and the sPESI. The association of PE-severity and in-hospital-mortality was assessed both in COVID and non-COVID patients, and the interaction of COVID status and PE severity/outcome associations was also evaluated.

Results: COVID patients had PEs of smaller size (43% vs 56% lobar or larger, 42% vs. 35% segmental and 13% vs. 9% subsegmental, respectively; p = 0.01 for trend), less RVD (22% vs. 16%, p =0.02) and lower sPESI (p =0.03 for trend). Risk of in-hospital death was higher in COVID patients (12.8% vs. 5.3%, p < 0.001). PE-severity assessed by RVD and sPESI was independently associated with in-hospital-mortality in COVID patients, while PE size and sPESI were significantly associated with in-hospital-mortality in non-COVID. COVID status showed a significant interaction in the association of PE size and outcome (p =0.01), with OR for in-hospital mortality in COVID and non-COVID patients with lobar or larger PE of 0.92 (95%CI=0.19-4.47) and 4.47 (95%CI=1.60-12.5), respectively. Sensitivity analyses using only PCR-confirmed COVID cases confirmed these results.

Conclusion: COVID patients present a differential clinical picture, with PE of less severity than in non-COVID patients. An increased sPESI was associated with the risk of mortality in both groups but, PE size did not seem to be associated with in-hospital mortality in COVID patients.