CT imaging of pulmonary embolism in patients with COVID-19 pneumonia: a retrospective analysis

Abstract

Objectives To describe imaging and laboratory findings of confirmed PE diagnosed in COVID-19 patients and to evaluate the characteristics of COVID-19 patients with clinical PE suspicion. Characteristics of patients with COVID-19 and PE suspicion who required admission to the intensive care unit (ICU) were also analysed. Methods A retrospective study from March 18, 2020, until April 11, 2020. Inclusion criteria were patients with suspected PE and positive real-time reverse-transcription polymerase chain reaction (RT-PCR) for SARS-CoV-2. Exclusion criteria were negative or inconclusive RT-PCR and other chest CT indications. CTPA features were evaluated and severity scores, presence, and localisation of PE were reported. d -dimer and IL-6 determinations, ICU admission, and previous antithrombotic treatment were registered. Results Forty-seven PE suspicions with confirmed COVID-19 underwent CTPA. Sixteen patients were diagnosed with PE with a predominant segmental distribution. Statistically significant differences were found in the highest d -dimer determination in patients with PE and ICU admission regarding elevated IL-6 values. Conclusion PE in COVID-19 patients in our series might predominantly affect segmental arteries and the right lung. Results suggest that the higher the d -dimer concentration, the greater the likelihood of PE. Both assumptions should be assessed in future studies with a larger sample size. Key Points • On CT pulmonary angiography, pulmonary embolism in COVID-19 patients seems to be predominantly distributed in segmental arteries of the right lung, an assumption that needs to be approached in future research. • Only the highest intraindividual determination of d -dimer from admission to CT scan seems to differentiate patients with pulmonary embolism from patients with a negative CTPA. However, interindividual variability calls for future studies to establish cut-off values in COVID-19 patients. • Further studies with larger sample sizes are needed to determine whether the presence of PE could increase the risk of intensive care unit (ICU) admission in COVID-19 patients.

Pulmonary Embolism Associated with COVID-19 Occurs in Predominantly Elderly Patients with Comorbidities: A Single Center Retrospective Study

“…PE occurred more frequently on the right side of the lung, was located typically into or near the CT detectable COVID-19 inflammatory changes and more often involved small-to medium diameter branches unilaterally or bilaterally. These results are generally in accordance with majority of recently published studies ( Espallargas et al, 2021 ; Grillet, 2020 ; Leonard-Lorant et al, 2020 ; Lodigiani et al, 2020 ; Planquette et al, 2021 ), who described PE distribution within pulmonary tree. The potential pathogenic mechanism proposed was an in situ microvascular thrombosis within diseased lung region mainly related to COVID-19 inflammation ( Wichmann et al, 2020 ) or concomitant endothelial injury effect ( Smadja et al, 2020 ), leading a possible explanation of a higher PE incidence in the small-diameter vessels in diseased lung region.…”

“…Possible mechanisms of thrombosis in found comorbidities were probably related to an endothelial injury or higher levels of inflammatory markers, common in physiopathology of these entities. Approximately two-weeks for the PE occurrence after COVID-19 onset is almost identical in all previous researches ( Espallargas et al, 2021 ; Planquette et al, 2021 ). However, in our study in three patients, PE occurred after being discharged from hospital, felt well for a short time and some of them even did not have any inflammatory consolidations visible at the time of CTPA scanning.…”

“…Radiologists noticed high incidence rate of the pulmonary embolism (PE), even despite thromboprophylaxis given. So far, there are several published case reports ( Brüggemann et al, 2020 ; Cellina & Oliva, 2020 ; Jafari et al, 2020 ) and researches ( Espallargas et al, 2021 ; Grillet, 2020 ; Karolyi et al, 2021 ; Leonard-Lorant et al, 2020 ; Lodigiani et al, 2020 ; Planquette et al, 2021 ) addressing the PE in a setting of COVID-19 infection. Literature showed the thrombotic complications occurred most often in seriously ill individuals ( Middeldorp et al, 2020 ) even without risk factors and in some cases even despite the given thromboprophylaxis.…”

Venous thromboembolism in COVID-19: A systematic review and meta-analysis

“…Ventura-Díaz et al 20 Espallargas et al 25 Mueller-Peltzer et al 26 Ramadan et al 27 Mouhat et al 30 Alonso-Fernández et al 32 Monfardini et al 39 Freund et al 40 Chen et al 41 Whyte et al 43 Fauvel et al 45 Larsen et al 48 Bavaro et al 51 Mazzaccaro et al 53 Gervaise et al 54 Poyiadji et al 60 Bompard et al 62 BDL Overall (I 2 = 94.8%) patients with severe COVID-19. 68 It has been suggested that SARS-Cov-2 in severe forms of the disease induces an excessive inflammatory state via cytokine storm combined with endothelial injury and pulmonary vascular microthrombosis, which could considerably increase the risk for VTE, mainly PE.…”

Plućni embolizam u pneumoniji

“…zirom na patofiziologiju CAC-a i ALI: uglavnom se viđaju sitniji tromboembolusi koji zahvaćaju upravo prostor u kojem postoji pneumonijski infiltrat, odnosno, ishodište najveće upalne aktivnosti (najčešće subsegmentalne arterije u desnom plućnom krilu). Sukladno tome, centralna opstrukcija i posljedično opterećenja desnog srca, viđaju se nešto rjeđe [31,32] .…”