Syncope on presentation is a surrogate for submassive and massive acute pulmonary embolism

Abstract

Introduction: There are conflicting data regarding the prognostic value of syncope in patients with acute pulmonary embolism (APE).

Methods: We retrospectively reviewed data of 552 consecutive adults with computed tomography pulmonary angiogram-confirmed APE to determine the correlates and outcome of the occurrence of syncope at the time of presentation.

Results: Among 552 subjects with APE (mean age 54years, 47% men), syncope occurred in 12.3% (68/552). Compared with subjects without syncope, those with syncope were more likely to have admission systolic blood pressure<90mmHg (odds ratio (OR) 5.788, P<0.001), and an oxygen saturation<88% on room air (OR 5.560, P<0.001), right ventricular dilation (OR 2.480, P=0.006), right ventricular hypokinesis (OR 2.288, P=0.018), require mechanical ventilation for respiratory failure (OR 3.152, P=0.014), and more likely to receive systemic thrombolysis (OR 4.722, P=0.008). On multivariate analysis, syncope on presentation was an independent predictor of a massive APE (OR 2.454, 95% CI 1.109-5.525, P=0.03) after adjusting for patients' age, sex, requirement of antibiotics throughout hospitalization, peak serum creatinine, admission oxygen saturation<88% and admission heart rate>100bpm. There was no difference in mortality in cases with APE with or without syncope (P=0.412).

Conclusion: Syncope at the onset of pulmonary embolization is a surrogate for submassive and massive APE but is not associated with higher in-hospital mortality.