Consideration of PE in Syncope
The Article: Prandoni P et al. Prevalence of Pulmonary Embolism Among Patients Hospitalized for Syncope. NEJM 2016; 375(16): 1524 – 31.
The Idea: Syncope is a common and yet often difficult chief complaint, with no gold standard test and no validated decision guideline. ED and inpatient workups are frequently low yield. PE is one of several more concerning possible diagnoses to consider, but there has previously been little evidence on its prevalence in syncopal patients. The PESIT trial published in 2016 attempted to provide some such data.
The Study: Multicenter, cross-sectional study from 11 Italian hospitals Outcome: prevalence of PE in patients with a first episode of syncope Exclusion criteria: prior syncopal episode, on anticoagulants, pregnant, lack of informed consent
Results: – 1857 (72%) patients either not admitted or declined hospitalization – 560 patients included (mean age was 76 years) – 330 of the 560 had PE ruled out with low probability Well’s score and negative D-dimer – 97 of the 230 remaining pts (via VQ or CTA) were determined to have PE (on CTA: main pulm artery 30, lobar 18, segmental 19, subsegmental 5) – PE was present in 45/355 patients patients (12.7%) who had an alternative explanation for syncope and 52/205 patients (25.4%) who did not – Prevalence was 17.3 % (1 in 6!)
The Takeaway: One in 6 patients with PE in first-time syncope is a daunting statistic. However, a closer look at the data reveals that the true number for all patients would in reality be 97 patients out of a total of 2584 patients, or 3.7%. Also, three-quarters of patients diagnoses with PE had tachycardia, tachypnea, a swollen leg, and/or hypotension. The most concerning subset—those without these symptoms and who still had PE, make up 0.9%. Also notable, are the high rates of prior VTE and cancer in patients with PE and syncope. The final take home should be to test for PE when suspected in syncope patients. Don’t start overtesting due to this article.