The Prevalence of Previous Coronavirus Disease-19 as a Predisposing Factor in Pulmonary Thromboembolism and its Effect on Embolism Severity: A Multicenter, Observational, Cross-Sectional Study
Authors: Koçak Nagihan Durmuş , Tutar Nuri , Çil Gizem , Afşin Emine , Şentürk Ayşegül , Aydın Derya , Mermit Buket , Parmaksız Elif Torun , Çolak Mustafa , Yıldırım Elif , Özyurt Songül , Erbay Gülru , Tanrıverdi Elif , Kaya İlknur , Yetkin Nur Aleyna , Uçar Elif Yılmazel , Doğru Sibel , Kilic Talat , Uçar Hatice Arzu , Berk Serdar , Çiçek Tuğba , Ozsari Emine , Kırkıl Gamze , Yakar Halil İbrahim , Alkılınç Ersin , Tabaru Ali , Yarar Esra , Aksoy Emine , Akkök Burcu , Parspur Şebnem Emine , Kurtipek Ercan , Uzer Fatih , Tapan Utku , Duman Dildar , Tatar Dursun , Karadeniz Gülistan , Hocanlı İclal , Tapan Özge Oral , Canoğlu Kadir , Bozkuş Fulsen , Arslan Nevra Gullu , Doğan Ömer Tamer , Taylan Mahşuk , Pala Ayşe 
Published: February 2024

Background
Knowledge of predisposing factors in developing pulmonary thromboembolism (PTE) is important in the diagnosis and treatment approach. The association between past coronavirus disease-19 (COVID-19) infection and PTE is a potential research topic. In this study we aimed to determine the prevalence of previous COVID-19 in addition to all predisposing factors for PTE development and to determine whether there is a difference in embolism severity in these cases.
Methods
Study design: Multicenter, observational, cross-sectional. Patients diagnosed with PTE between March 11, 2022, and March 11, 2023, were prospectively included in the study. Group 1: PTE cases with previous COVID-19, Group 2: PTE cases without previous COVID-19. To compare the categorical variables between groups the chi-square test was used. For continuous variables, parametric and non-parametric tests were used. Multivariate binary logistic regression analysis was performed to determine the independent variables related to PTE severity that affected the presence of previous COVID-19.
Results
Forty-four researchers from 33 centers participated in our study. A total of 1185 patients were included (Group 1; n = 360, Group 2; n = 825). The median post-COVID duration was 120.0 (min-max: 30–980) days. Computed tomography pulmonary angiography (CTPA) right ventricle/left ventricle (RV/LV) ratio > 1 was significantly higher in Group 2 compared to Group 1 (27.9% vs 19.7%, p = 0.003).The proportion of patients receiving systemic thrombolytic drugs (11.3% vs. 7.5%, p = 0.048), and the rate of patients who started treatment in the intensive care unit was higher in Group 2 (23.4% vs. 14.7%, p = 0.001). In multivariate logistic regression analysis, the absence of any identifiable risk factor for PTE was found to be a 0.46-fold protective factor in the presence of previous COVID-19 (95% CI: 0.274–0.760, p = 0.003) and an RV/LV ratio > 1 on CTPA was found to be a 0.60-fold protective factor (95% CI: 0.365–0.998, p = 0.049).
Conclusions
The prevalence of previous COVID-19 infection in PTE cases was 30.4%, and 26% of idiopathic cases had previous COVID-19 infection. Although the parameters related to embolism severity were higher in the non-COVID-19 group, in multivariate analyses, only idiopathic status was associated with a 2.2-fold increased risk in non-COVID-19 patients compared to those who had, and an RV/LV ratio > 1 on CTPA was associated with a 1.7-fold increased risk.