{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T10:49:54Z","timestamp":1789728594100,"version":"4.0.1"},"reference-count":26,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T00:00:00Z","timestamp":1771804800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Pulmonary embolism (PE) is a frequent thrombotic complication associated with SARS-CoV-2 infection and is linked to significant early mortality. Accurate early risk stratification in the emergency department (ED) remains challenging, and it is unclear how well commonly used PE prognostic tools perform in patients with concomitant COVID-19. Materials and Methods: We conducted a retrospective, single-centre study including 538 consecutive patients with acute PE and with or without confirmed SARS-CoV-2 infection admitted through the ED. Univariate analysis and machine learning models were employed to assess mortality risk. Results: In univariate analysis, mortality was strongly associated with sepsis (OR 11.68) and PESI class V (OR 5.56) and was also linked to higher neutrophil count (OR 1.19), platelet count (OR 1.12), and NT-proBNP (OR 1.20). In the non-COVID cohort, XGBoost and RF showed better discrimination than PESI class (AUC 0.864 and 0.834 vs. 0.725), while Support Vector Machines (SVM) was lower (AUC 0.740). On COVID-19 external validation, discrimination decreased: XGBoost AUC was 0.635, RF 0.614, PESI 0.584, and SVM showed no discrimination. Conclusions: ML models using routinely available ED variables improved in-hospital mortality prediction compared with PESI in non-COVID PE, but performance declined in COVID-19 patients, suggesting limited generalizability and the need for COVID-specific refinement and prospective multicenter validation.<\/jats:p>","DOI":"10.3390\/medicina62020421","type":"journal-article","created":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T11:39:10Z","timestamp":1771846750000},"page":"421","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Predicting Mortality in Pulmonary Embolism: A Machine Learning Approach with External Validation in COVID-19 Patients"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-5258-670X","authenticated-orcid":false,"given":"Diana Alexandra","family":"M\u00ee\u021bu","sequence":"first","affiliation":[{"name":"Doctoral School, Faculty of General Medicine, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"},{"name":"Department of Internal Medicine, Emergency Clinical Municipal Hospital, 300254 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-7935-4471","authenticated-orcid":false,"given":"Alexandru Cristian","family":"Cindrea","sequence":"additional","affiliation":[{"name":"Doctoral School, Faculty of General Medicine, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"},{"name":"Emergency Department, Emergency Clinical Municipal Hospital, 300254 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra Maria","family":"Borita","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Emergency Clinical Municipal Hospital, 300254 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8978-3168","authenticated-orcid":false,"given":"Adina Maria","family":"Marza","sequence":"additional","affiliation":[{"name":"Emergency Department, Emergency Clinical Municipal Hospital, 300254 Timisoara, Romania"},{"name":"Department of Surgery, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-1714-6830","authenticated-orcid":false,"given":"Cornelu\u021ba","family":"Fira-Mladinescu","sequence":"additional","affiliation":[{"name":"Discipline of Hygiene, Department of Microbiology, Center for Studies in Preventive Medicine, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2375-2793","authenticated-orcid":false,"given":"Madalin-Marius","family":"Margan","sequence":"additional","affiliation":[{"name":"Discipline of Public Health, Department of Functional Sciences, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"},{"name":"Center for Translational Research and Systems Medicine, Faculty of Medicine, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra","family":"Herlo","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, \u201cVictor Babes\u201d University of Medicine and Pharmacy, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0699-710X","authenticated-orcid":false,"given":"Alina","family":"Petrica","sequence":"additional","affiliation":[{"name":"Department of Surgery, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"},{"name":"Emergency Department, \u201cPius Brinzeu\u201d Emergency Clinical County Hospital, 300736 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriel-Aurel","family":"Rus","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, Emergency Clinical Municipal Hospital, 300254 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel-Florin","family":"Lighezan","sequence":"additional","affiliation":[{"name":"Department of Medical Semiology I, \u201cVictor Babes\u201d University of Medicine and Pharmacy, No. 2 Eftimie Murgu Square, 300041 Timisoara, Romania"},{"name":"Advanced Cardiology and Hemostaseology Research Center, \u201cVictor Babes\u201d University of Medicine and Pharmacy, No. 2 Eftimie Murgu Square, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5755-179X","authenticated-orcid":false,"given":"Flavia","family":"Zara","sequence":"additional","affiliation":[{"name":"Department II of Microscopic Morphology, \u201cVictor Babes\u201d University of Medicine and Pharmacy, E. Murgu Square, No. 2, 300041 Timisoara, Romania"},{"name":"Angiogenesis Research Center, \u201cVictor Babes\u201d University of Medicine and Pharmacy, E. Murgu Square, No. 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2242-7764","authenticated-orcid":false,"given":"Ovidiu Alexandru","family":"Mederle","sequence":"additional","affiliation":[{"name":"Emergency Department, Emergency Clinical Municipal Hospital, 300254 Timisoara, Romania"},{"name":"Department of Surgery, \u201cVictor Babes\u201d University of Medicine and Pharmacy, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,23]]},"reference":[{"key":"ref_1","first-page":"7","article-title":"Pulmonary Embolism: An International Crisis","volume":"18","author":"Weinberg","year":"2019","journal-title":"Endovasc. 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