Clinical Outcome Related to Diagnosis of Saddle Pulmonary Embolism using Computed Tomographic Angiography in an Emergency Department

Kim, Hoi Won; Kim, Won Young; Sohn, Chang Hwan; Seo, Dong Woo; Lee, Jae Ho; Kim, Won; Lim, Kyoung Soo

Abstract

PURPOSE
Saddle embolism (SE) is defined as a thromboembolus located at the bifurcation of the main pulmonary artery. The aim of this study was to determine the prognostic significance of SE as diagnosed by computed tomographic (CT) angiography in patients with submassive pulmonary embolism (PE).
METHODS
Between July 2006 and June 2010, 223 consecutive patients diagnosed with submassive PE using contrast enhanced CT angiography in an emergency department were assessed. One experienced radiologist evaluated the CT results, searching for any presence of SE. The clinical information including echocardiographic findings and outcomes for all patients was reviewed. The presence of SE was determined in order to assess its predictive power for major adverse events (MAE) within 1 month (shock, intubation, mortality, thrombolysis and thrombectomy).
RESULTS
Sixteen out of 223 patients (7.2%) were found to have a SE. Overall mortality at 1 month was 13.5% with no difference between SE and non-SE patients (12.6% vs. 25.0%, p=0.16). SE patients had a significantly higher rate of MAE (27.5% vs. 62.5%, p=0.01). The presence of SE and the observation of a D-shaped left ventricle by echocardiography were associated with an odds ratio of the occurrence of MAE of 3.75 (95% Confidence Interval: 1.22-11.31, p=0.02), 2.94 (95% Confidence Interval: 1.39-6.22, p<0.01).
CONCLUSION
SE, as diagnosed by CT angiography, was associated with submassive PE related shock, intubation, mortality, thrombolysis and thrombectomy within 1 month of observation.