Spiral CT angiography for suspected pulmonary embolism: a cost-effectiveness analysis.

PURPOSE To investigate the cost-effectiveness of diagnostic strategies involving spiral computed tomographic (CT) or conventional pulmonary angiography in the diagnosis of suspected pulmonary embolism. MATERIALS AND METHODS A model was created for analyzing cost-effectiveness on the basis of available literature data. Diagnostic algorithms consisting of combinations of perfusion and ventilation scintigraphy, ultrasound, D-dimer assay, conventional angiography, and spiral CT angiography were compared. Preference for strategies was determined on the basis of the mortality and cost per life saved. RESULTS For all realistic values of the pretest probability of pulmonary embolism and coexisting deep vein thrombosis and of the specificity of spiral CT angiography, all of the best strategies included spiral CT angiography. With an assumed sensitivity for spiral CT angiography of less than 85%, a conventional angiographic strategy yielded a lower mortality but did not yield superior cost-effectiveness. CONCLUSION The use of spiral CT angiography is likely to reduce the mortality and improve cost-effectiveness in the diagnostic work-up of suspected pulmonary embolism.