Blood Clot in Lungs Rare in Patients at Emergency Department After Fainting

JAMA Internal Medicine


Media advisory: To contact authors Giorgio Costantino, M.D., email or  Nicola Montano, M.D., Ph.D., at full study is available on the For The Media website.

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Bottom Line: A blood clot in the lungs was rarely identified in patients who went to the emergency department after fainting.

Why The Research Is Interesting: Fainting (known as syncope) is a common symptom people can experience. A blood clot in the lungs (known as a pulmonary embolism or PE) has been recognized as a serious cause of syncope but data are scant and the evidence is conflicting on how frequent that is the case.

Who and When: More than 1.6 million adults who went to an emergency department for syncope in five databases in four countries (Canada, Denmark, Italy and the United States); data collected from 2010 to 2016

What (Study Measures): Frequency of PE at emergency department and hospital discharge identified by diagnosis codes (primary outcome)

How (Study Design): This was an observational study. Researchers were not intervening for purposes of the study and they cannot control all the natural differences that could explain the study findings.

Authors: Giorgio Costantino, M.D., of the Fondazione Instituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy, and coauthors

Results: The frequency of PE diagnosis ranged from 0.06 percent to 0.55 percent of all patients who went to the emergency department for syncope; among hospitalized patients, the frequency ranged from 0.15 percent to 2.10 percent.

Study Limitations: The main limitation is using administrative data to identify patients with syncope and PE because patients can be missed.

Study Conclusions:


Related Material: A podcast with author Nicola Montano, M.D., Ph.D., of the University of Milan, Italy, also is available for preview on the For The Media website.


For more details and to read the full study, please visit the For The Media website.


Editor’s Note: The article contains conflict of interest and funding/support disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

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