In-Hospital versus Out-of-Hospital Pulmonary Embolism: Clinical Characteristics, Biochemical Markers and Echocardiographic Indices

Background: A significant proportion of pulmonary embolisms (PEs) occurs in patients during hospitalisation for another reason. However, limited data regarding differences between out-of-hospital PE (OHPE) and in-hospital PE (IHPE) is available. We aimed to compare these groups regarding their clinical characteristics, biochemical markers, and echocardiographic indices. Methods: This was a prospective, single-arm, single-centre study. Adult consecutive patients with non-COVID-related PE from September 2019 to March 2022 were included and followed up for 12 months. Results: The study included 180 (84 women) patients, with 89 (49.4%) suffering from IHPE. IHPE patients were older, they more often had cancer, were diagnosed earlier after the onset of symptoms, they had less frequent pain and higher values of high sensitivity troponin I and brain natriuretic peptide levels compared to OHPE patients. Echocardiographic right ventricular (RV) dysfunction was detected in similar proportions in the 2 groups. IHPE had increased in-hospital mortality (14.6% vs. 3.3%, p = 0.008) and similar post-discharge to 12-month mortality with OHPE patients. Conclusions: In this prospective cohort study, IHPE differed from OHPE patients regarding age, comorbidities, symptoms, and levels of biomarkers associated with RV dysfunction. IHPE patients had higher in-hospital mortality compared to OHPE patients and a similar risk of death after discharge.