Is syncope a predictor of mortality in acute pulmonary embolism?

Whether syncope as a presenting symptom independently classifies acute pulmonary embolism (APE) into a high mortality risk group remains a matter of controversy. We retrospectively included all consecutive patients admitted to our clinic with APE from January 2014 to December 2016. Our sample consisted of 76 patients with a mean age of 69 ±13.6 years, 64.5% female. 14.3% presented with syncope at admission. In-hospital mortality was 20.8%. Patients with syncope were more likely to require inotropic support (OR = 5.2, 95 % 1.17-23.70, p=0.03) due to the association of cardiogenic shock (OR= 15.95% CI 3.02-74.32, p < 0.001) and systolic blood pressure below 90 mmHg (OR=5.52, 95% CI 1.24-24.47, p=0.03). Patients with syncope had a higher PESI score (150.9 ± 51.1 vs 99.9 ± 30.1, p < 0.001) and a greater in-hospital mortality (OR= 4.5, 95% CI 1.14-17.62, p=0.03). However, multivariate logistic regression equations did not identify syncope as an independent predictor of mortality. In our sample, syncope did not independently reclassify the patient in a higher mortality group, but due to the association with hemodynamic instability, which remains the primary tool in therapeutic decision-making.