Right ventricular dilation on CT pulmonary angiogram independently predicts mortality in pulmonary embolism.
BACKGROUND
The aim of this study was to determine the prognostic significance of right ventricular dilation on CT pulmonary angiogram in acute pulmonary embolism and to distinguish if this feature predicts mortality independently of the Pulmonary Embolism Severity Index, an established admission severity score.


METHODS
A retrospective study of patients admitted with pulmonary embolism confirmed by CT pulmonary angiogram to three teaching hospitals in East Scotland between January 2005 and July 2007. Two radiologists judged presence of right ventricular dilation on CT pulmonary angiogram independently. The outcome of interest was 30 day mortality. Multivariable logistic regression was used to compare this outcome in patients with right ventricular dilation compared to those without right ventricular dilation, adjusting for Pulmonary Embolism Severity Index score.


RESULTS
There were 585 patients included and 30.4% had right ventricular dilation on CT pulmonary angiogram. Patients with right ventricular dilation had increased 30 day mortality rates compared to patients without right ventricular dilation (12.4% vs. 5.4%; p=0.006). Survival analysis showed that a significantly greater proportion of deaths in the right ventricular dilation group occurred within the first 48h after admission compared to the group without right ventricular dilation (45.5% deaths vs. 9.1%; p=0.016). On multivariable analysis, adjusting for Pulmonary Embolism Severity Index score, right ventricular dilation was independently associated with increased 30 day mortality (OR 2.98; 95% CI 1.54-5.75; p=0.001).


CONCLUSION
Right ventricular dilation on CT pulmonary angiogram is an independent predictor of 30 day mortality in acute pulmonary embolism.