Prevalence of pulmonary embolism in patients presenting to the emergency department with syncope.

OBJECTIVES: A recent study reported a high prevalence of pulmonary embolism (PE) among patients admitted with syncope. We sought to determine whether these findings were validated in our patient population.

METHODS: We performed a retrospective, secondary analysis of prospectively gathered data from patients presenting with syncope to an academic emergency department (ED) from July 2010 to December 2015. We analyzed baseline information from the time of the ED visit, recorded outcomes during the hospital stay, and contacted patients by phone at least 30days after the ED visit. The primary study outcome was the diagnosis of acute PE in the ED, during inpatient admission or ED observation unit stay, or by patient report over a 30-day follow-up period.

RESULTS: Over the 5.5-year study period, 348 patients with syncope agreed to participate in the study. 52% of patients were female [95% confidence interval (CI): 46.6-57.4] and the average age was 48.4years. Of the enrolled patients, 50.1% (CI: 44.8-55.2) underwent further evaluation for syncope beyond the ED stay: 27% (CI: 22.6-31.9) of patients were admitted to an inpatient unit for further work-up and 23.9% (CI: 19.7-28.6) of patients were placed in the ED observation unit. The overall rate of PE among patients presenting to the ED with syncope was 1.4% (CI: 0.6-3.3%). 2 patients (0.6%, CI: 0.2-2.1) were diagnosed with a PE while in the ED. None of the patients were diagnosed with a PE during hospital admission or the observation stay associated with the index ED visit. 3 patients (0.9%, CI: 0.3-2.5) reported they had been diagnosed with a PE during the 30days following their ED visit, two of whom had been admitted to the hospital at the index ED visit but were not diagnosed with a PE at that time. All patients diagnosed with a PE at the time of the ED visit or during the follow-up period were Pulmonary Embolism Rule Out Criteria (PERC) positive and reported shortness of breath in the ED.

CONCLUSION: In contrast to a previous study, our findings do not support a high rate of PE among ED patients presenting with syncope.