Background: Acute pulmonary embolism (PE) represents a frequent and prognostically relevant complication of COVID-19.
Methods: We performed a systematic review and meta-analysis, according to the PRISMA guidelines to determine the in-hospital incidence of acute PE, based on Italian studies published on this issue. We searched PubMed and Scopus to locate all articles published between February 2020 to October 15, 2021, reporting the incidence of acute PE in Italian COVID-19 patients. The pooled in-hospital incidence of acute PE was calculated using a random-effect model and presented with relative 95% confidence interval (CI).
Results: We analysed data from 3287 Italian COVID-19 patients (mean age 65.7 years) included in 20 studies. The pooled in-hospital incidence of acute PE was 20% (95% CI 13.4-28.7%; I2 = 95.1%); the incidence was lower among patients hospitalized in intensive care unit (ICU) (32.3%; 95% CI 20.2-44.0%; I2 = 77.2%) compared to those admitted in general wards (47.6%; 95% CI 18.7-78.2%; I2 = 94.4%). Meta-regression showed a significant direct correlation of acute PE incidence using age, male gender and previous coronary artery disease as moderating variables. Conversely, an inverse correlation was observed in relation to the use of anticoagulation at therapeutic dose. Prophylactic and therapeutic anticoagulation was administered in 80.2% of patients (95% CI 72.5-86.2%; I2 = 91.0%); the former regimen was more frequently used compared to the latter (63.5% vs 14.3%; p<0.001). Computed tomography angiography (CTPA) was used only in 10.7% of infected patients across 7 studies.
Conclusions: One in five COVID-19 patients experienced acute PE as complication of the infection during hospitalization. The in-hospital incidence of acute PE was lower in ICU compared to general wards. CTPA was scantly used. Early prophylactic anticoagulation was associated with a lower incidence of acute PE.