Non-severe pulmonary embolism: prognostic CT findings

Abstract

The goal of this study was to retrospectively evaluate CT cardiovascular parameters and pulmonary artery clot load score as predictors of 3-month mortality in patients with clinically non-severe pulmonary embolism (PE). We included 226 CT positive for PE in hemodynamically stable patients (112 women; mean age 67.1 years ± 16.9). CT were independently reviewed by two observers. Results were compared with occurrence of death within 3 months using Cox regression. Twenty-four (10.6%) patients died, for whom 9 were considered to be due to PE. Interobserver agreement was moderate for the shape of interventricular septum (κ = 0.41), and for the ratio between the diameters of right and left ventricle (RV/LV) (κ = 0.76). Observers found no association between interventricular septum shape and death. A RV/LV diameter ratio >1 was predictive of death (OR, 3.83; p < 0.01) only when we also took into account the value of the embolic burden (< 40%). In a multivariate model, CT cardiovascular parameters were not associated with death. Concomitant lower limb DVT and comorbid conditions were important predictors of death. In clinically non-severe PE, a RV/LV diameter ratio >1 is predictive of death when the embolic burden is low (< 40%).