Pulmonary Embolism in COVID-19: The Actual Prevalence Remains Unclear

Pulmonary embolism in hospitalized COVID-19 patients: Short- and long-term clinical outcomes

Introduction

Pulmonary embolism (PE) is a frequent complication in COVID-19. However, the influence of PE on the prognosis of COVID-19 remains unclear as previous studies were affected by misclassification bias. Therefore, we evaluated a cohort of COVID-19 patients whom all underwent systematic screening for PE (thereby avoiding misclassification) and compared clinical outcomes between patients with and without PE.

Materials and methods

We included all COVID-19 patients who were admitted through the ED between April 2020 and February 2021. All patients underwent systematic work-up for PE in the ED using the YEARS-algorithm. The primary outcome was a composite of in-hospital mortality and ICU admission. We also evaluated long-term outcomes including PE occurrence within 90 days after discharge and one-year all-cause mortality.

Results

637 ED patients were included in the analysis. PE was diagnosed in 46 of them (7.2%). The occurrence of the primary outcome did not differ between patients with PE and those without (28.3% vs. 26.9%, p = 0.68). The overall rate of PE diagnosed in-hospital (after an initial negative PE screening in the ED) and in the first 90 days after discharge was 3.9% and 1.2% respectively. One-year all-cause mortality was similar between patients with and without PE (26.1% vs. 24.4%, p = 0.83).

Conclusions

In a cohort of COVID-19 patients who underwent systematic PE screening in the ED, we found no differences in mortality rate and ICU admissions between patients with and without PE. This may indicate that proactive PE screening, and thus timely diagnosis and treatment of PE, may limit further clinical deterioration and associated mortality in COVID-19 patients.

Systematic screening versus clinical gestalt in the diagnosis of pulmonary embolism in COVID-19 patients in the emergency department

BACKGROUND

Diagnosing concomitant pulmonary embolism (PE) in COVID-19 patients remains challenging. As such, PE may be overlooked. We compared the diagnostic yield of systematic PE-screening based on the YEARS-algorithm to PE-screening based on clinical gestalt in emergency department (ED) patients with COVID-19.

METHODS

We included all ED patients who were admitted because of COVID-19 between March 2020 and February 2021. Patients already receiving anticoagulant treatment were excluded. Up to April 7, 2020, the decision to perform CT-pulmonary angiography (CTPA) was based on physician's clinical gestalt (clinical gestalt cohort). From April 7 onwards, systematic PE-screening was performed by CTPA if D-dimer level was ≥1000 ug/L, or ≥500 ug/L in case of ≥1 YEARS-item (systematic screening cohort).

RESULTS

1095 ED patients with COVID-19 were admitted. After applying exclusion criteria, 289 were included in the clinical gestalt and 574 in the systematic screening cohort. The number of PE diagnoses was significantly higher in the systematic screening cohort compared to the clinical gestalt cohort: 8.2% vs. 1.0% (3/289 vs. 47/574; p<0.001), even after adjustment for differences in patient characteristics (adjusted OR 8.45 (95%CI 2.61-27.42, p<0.001) for PE diagnosis). In multivariate analysis, D-dimer (OR 1.09 per 1000 μg/L increase, 95%CI 1.06-1.13, p<0.001) and CRP >100 mg/L (OR 2.78, 95%CI 1.37-5.66, p = 0.005) were independently associated with PE.

CONCLUSION

In ED patients with COVID-19, the number of PE diagnosis was significantly higher in the cohort that underwent systematic PE screening based on the YEARS-algorithm in comparison with the clinical gestalt cohort, with a number needed to test of 7.1 CTPAs to detect one PE.

Risk factors and mortality of pulmonary embolism in COVID-19 patients: Evidence based on fifty observational studies

BACKGROUND

At present, many studies have described acute pulmonary embolism (PE) as a frequent and prognostically relevant complication of coronavirus disease 2019 (COVID-19) infection. Thus we performed the present analysis of 50 studies to evaluate the risk factors and mortality of PE in COVID-19 patients.

METHOD

Databases including PubMed, Embase, Cochrane Library and Web of Science were searched to October, 2021. Odds ratio (OR), mean difference (MD) or standard MD was used to evaluate the outcomes. The primary outcomes were the difference of mortality between PE and non-PE COVID-19 patients as well as relevant risk factors of PE in COVID-19 patients. All statistical analyses were performed using the standard statistical procedures provided in Review Manager 5.2.

RESULT

A total of 50 studies including 10053 patients were included in this meta-analysis. Our results indicated that COVID-19 patients with PE experienced significantly higher mortality than non-PE patients (21.9% vs. 10.7%), with a pooled OR of 2.21 (95% CI 1.30 - 3.76; P = .003). In addition, COVID-19 patients with PE also experienced more mechanical ventilation (MV) (OR 2.21; 95% CI 1.30 - 3.75; P = .003) and invasive mechanical ventilation (IMV) (OR 3.58; 95% CI 2.47 - 5.20; P < .0001) respectively. Univariate analysis (UVA) results indicated the Sequential Organ Failure Assessment (SOFA) score, time to deep venous thrombosis (DVT), nonintensive care unit (non-ICU) patients and no anticoagulation as risk factors of PE for COVID-19 patients. In addition, multivariate analysis also found that SOFA score, D-dimer, BMI > 30 kg/m2 and history of PE were risk factors of PE for COVID-19 patients.

CONCLUSION

The present analysis indicated that PE increased the mortality of COVID-19 patients. Mechanical ventilation, especially invasive mechanical ventilation, is correlated with an increased incidence of PE in patients with COVID-19. The incidence of PE for COVID-19 patients may be multifactorial and further researches focused on risk factors were needed in the future.

One Year Prevalence of Venous Thromboembolism in Hospitalized COVID-19 Patients in France: Patients' Characteristics, Time Trends, and Outcomes

BACKGROUND

 Patients hospitalized with coronavirus disease-2019 (COVID-19) are at high risk of deep venous thrombosis (DVT) and pulmonary embolism (PE).

OBJECTIVES

 The aims were to provide time trends in the 2020 nation-wide prevalence of venous thromboembolism (VTE) in patients hospitalized with a COVID-19 diagnosis in France, and to describe in-hospital and up to 30-day postdischarge death.

METHODS

 All patients hospitalized in France with a COVID-19 diagnosis in 2020 were selected. Crude and age-adjusted prevalence of VTE and PE was computed by 4-week intervals and for the overall study period using Poisson regression. Time trends in in-hospital and 30-day postdischarge case-fatality rates were evaluated by comparing each 4-week intervals to weeks 10 to 14 corresponding to the first part of the first lockdown using logistic regression models.

RESULTS

 Among the 287,638 patients hospitalized with a COVID-19 diagnosis in 2020 in France, 14,985 (5.2%) had a concomitant VTE, with 10,453 (3.6%) having PE and 4,532 (1.6%) having DVT. In patients admitted to intensive care units, the crude prevalence of VTE and PE reached 16.1 and 11.0% respectively during the first lockdown. After adjustment, the prevalence of VTE and PE decreased during the year 2020 but a rebound was observed during the second lockdown. In-hospital case-fatality rates among hospitalized COVID-19 patients with PE globally decreased between the first and the second epidemic waves.

CONCLUSION

 Our study showed a decrease in the incidence of symptomatic VTE and PE in hospitalized COVID-19 patients, and a decreased time trend of outcomes during the second wave compared with the first one.