Long term follow-up of a multicentre cohort of COVID-19 patients with pulmonary embolism: Anticoagulation management and outcomes.

Background And Aims: Pulmonary embolism (PE) is a frequent complication in COVID19 hospitalized patients. Inflammatory storm and endothelial dysfunction due to the virus seem to be the two major risk factors for PE. Consequently, PE related to COVID19 could be consider as triggered by a transient inflammatory acute phase and treated for no longer than 3 months. However, few data are available on management of anticoagulation and risk of venous thromboembolic (VTE) recurrences in these patients and guidelines are still undefined. Aim of the present study is to evaluate the long-term follow-up of a cohort of covid-19 patients with PE.

Methods: We conducted a retrospective multicenter study in four Italian hospitals between March 1st, 2020, and May 31st, 2021 in patients who experienced a PE during hospitalization for a COVID-19 pneumonia, excluding patients who died during hospitalization. Baseline characteristics were collected and patients were grouped according to duration of anticoagulant treatment (< 3 months or > 3 months). The primary outcome was incidence of VTE recurrence while secondary outcome was the composite of deaths, major hemorrhages and VTE recurrence during follow-up.

Results: 106 patients with PE were discharged, of these 95 (89.6 %) had follow up longer than 3 months (seven patients were lost to follow up and four died within three months). The median follow-up was 13 months (IQR 1-19). Overall, 23 % of subjects (22/95) were treated for 3 months or less and 76.8 % (73/95) received anticoagulation for >3 months. Of patients in the short treatment group, 4.5 % died, compared with 5.5 % of those in the longer treatment group (p = NS); no difference was shown in risk of VTE recurrence (0 % vs 4.1 %, p = NS), major bleeding (4.5 % vs 4.1 %, p = NS) or in composite outcome (9.1 % vs 11 %, p = NS). No difference was found between the two treatment groups for composite outcome using the Kaplan-Meier analysis (Log Rank Test p = 0.387).

Conclusion: In our retrospective multi-center cohort, prolongation of duration of anticoagulation seems not to affect risk of VTE recurrences, deaths and bleeding after a PE related to COVID-19.