Diagnostic Delay of Pulmonary Embolism Faced by COVID-19 Patients: a Real-Life Experience from San Matteo Hospital of Pavia, an Academic Referral Center

Pulmonary embolism (PE) is a frequent, life-threatening complication of COVID-19, whose diagnosis can be challenging due to its non-specific signs and symptoms. To date, there are no cohort studies assessing the impact of the diagnostic delay of COVID-19-associated PE. Hence, the aim of our study is to assess the diagnostic delay of PE in COVID-19 patients and to identify the patient-related and physician-related variables associated with the delay. This is a single-center observational, retrospective study of all the COVID-19 patients admitted to the San Matteo Hospital Foundation between February and May 2020, with a diagnosis of PE, and a control population of non-COVID-19 patients admitted to San Matteo hospital during the same time lapse in 2019. The diagnostic delay was defined by the calculation of the patient-related delay (i.e. the time between the symptom onset and the first medical examination), and the physician-related delay (i.e. the time between the first medical examination and the diagnosis of PE). The overall diagnostic delay had a significant correlation with the physician-related delay (p<0.0001), in which a long physician-related diagnostic delay was often associated with a worse prognosis (p=0.04). The delay could be appreciated clinically by the presence of fever, respiratory symptoms and high levels of lactate dehydrogenase. By evaluating the diagnostic delay and its associated variables, prompt identification or exclusion of PE is possible. This, in turn, will allow prompt and appropriate therapy, improve clinical outcome and shorten the length of hospitalization of COVID-19 patients.