FROM THE NEW ENGLAND JOURNAL OF MEDICINE
When specifically looked for, pulmonary embolism was identified in approximately 17% of adults hospitalized for a first episode of syncope, according to a report published in the New England Journal of Medicine.
Most medical textbooks include pulmonary embolism (PE) in the differential diagnosis of syncope, but “current international guidelines, including those from the European Society of Cardiology and the American Heart Association, pay little attention to establishing a diagnostic workup for PE in these patients. Hence, when a patient is admitted to a hospital for an episode of syncope, PE – a potentially fatal disease that can be effectively treated – is rarely considered as a possible cause,” said Paolo Prandoni, MD, PhD, of the vascular medicine unit, University of Padua (Italy), and his associates in the PESY (Prevalence of Pulmonary Embolism in Patients With Syncope) trial.
The investigators used a systematic diagnostic work-up to determine the prevalence of PE in a cross-sectional study involving 560 adults hospitalized for syncope at 11 medical centers across Italy during a 2.5-year period. Most of these patients were elderly (mean age, 76 years), and most had clinical evidence indicating that a factor other than PE had caused their fainting. For this study, syncope was defined as a transient loss of consciousness with rapid onset, short duration (less than 1 minute), and spontaneous resolution, with obvious causes ruled out (such as epileptic seizure, stroke, or head trauma).
PE was ruled out in 330 patients who had a low clinical probability of the disorder or a negative D-dimer assay. Of the remaining 230 patients, 135 (58.7%) had a positive D-dimer assay suggesting PE, 3 (1.3%) had a high pretest clinical probability of PE, and 92 (40.0%) had both. PE was then confirmed using CT or ventilation-perfusion scanning in 97 of these 135 patients.
The “unexpectedly high” prevalence of PE was 17.3% overall, and it was consistent, ranging from 15% to 20%, across all 11 hospitals. The prevalence was even higher, at 25.4%, in the subgroup of 205 patients who had syncope of undetermined origin, as well as in 12.7% of the subgroup of 355 patients considered to have an alternative explanation for the disorder, Dr. Prandoni and his associates wrote ( N Engl J Med. 2016 Oct 20. doi: 10.1056/NEJMoa1602172 ).
The researchers noted that this study likely underestimates the actual prevalence of PE among patients with syncope because it did not include patients who were not hospitalized, such as those who received only ambulatory care and those who presented to an emergency department but were not admitted.
The study was supported by the University of Padua. Dr. Prandoni and his associates reported having no relevant financial disclosures.
