AJR:195, October 2010
Halil Dogan, Lucia J. M. Kroft, Menno V. Huisman, Rob van der Geest, Ying Li O, Hildo J. Lamb, Albert de Roos
OBJECTIVE. The purpose of this article is to determine the independent predictors of right ventricular (RV) dysfunction in patients with acute pulmonary embolism (PE) and to as¬sess the relationship between RV ejection fraction (EF) and PE load.
SUBJECTS AND METHODS. Breath-hold CT of the chest was performed for 64 pa¬tients with PE (33 men and 31 women; mean [± SD] age, 58.6 ± 16.5 years). In addition. ECG-synchrdnized cardiac CT was performed to determine the RV and left ventricular (LV) EFs. PE load was determined using the Qanadli obstruction index. Multivariable regression analy¬sis was performed to determine independent predictors of RV dysfunction (defined as EF < 35%). In addition, the relationship between RV EF and PE load was assessed by receiver op-crating characteristic (ROC) curves.
RESULTS. RV dysfunction was independently predicted by a PE load greater than 50% (odds ratio, 40.17; 95% CI, 4.22-382.67) and an LV EF less than 45% (odds ratio. 31.18; 95% CI, 2.00-487.09; p < 0.05 for both). Curve analysis revealed that a PE load greater than 50% had a sensitivity of 82% and a specificity of 85% to identify an RV EF less than 35%. Con-versely, an RV EF less than 35% had a sensitivity of 93% and a specificity of 67% to predict a PE load greater than 50%.
CONCLUSION. RV dysfunction (defined as RV EF < 35%) in patients with acute PE is highly sensitive to define a PE load greater than 50%. Furthermore, RV dysfunction is inde¬pendently predicted by an obstruction index greater than 50% or an LV EF less than 45%. As¬sessment of RV function by ECG-synchronized CT may become useful for guiding therapy.