Central emboli rather than saddle emboli predict adverse outcomes in patients with acute pulmonary embolism

In patients with acute pulmonary embolism (PE), the prognostic implications of saddle or central emboli, as observed on computed tomography (CT), remain to be established. The aim of the present study was to assess whether the presence of saddle and central emboli could be used to predict clinical outcomes in patients with PE.

The authors retrospectively reviewed 743 consecutive patients hospitalized at a tertiary referral center with a diagnosis of PE based on multi-detector row CT scan.

All the clinical variables did not differ between saddle emboli (5.8% [n = 43]) and right or left pulmonary artery emboli (29.7% [n = 221]), and the frequency of an adverse outcome was not significantly different between the two groups. Saddle emboli and right or left pulmonary artery emboli were grouped into central emboli (35.5% [n = 264]). Patients were allocated to an adverse outcome group (10.5% [n = 78]) or a control group (89.5% [n = 665]). Multivariate analysis demonstrated that PE severity index (PESI) score (class IV-V), N-terminal-pro-B-type natriuretic peptide level (≥ 1,406 pg/mL), right ventricular dilation on CT (right ventricle/left ventricle diameter ratio ≥ 1), and central emboli significantly predicted an adverse outcome. The addition of central emboli to other established prognostic factors such as PESI enhanced the positive predictive values and positive likelihood ratios of an adverse outcome for acute PE.

Rather than saddle emboli, central emboli could be an independent prognostic factor of adverse outcomes in patients with acute PE and provide additional prognostic value when combined with other prognostic factors.