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Pulmonary embolism: diagnosis in 211 patients with use of selective pulmonary digital subtraction angiography with a flow-directed catheter.

PURPOSE
To evaluate image quality, safety, and clinical validity of selective, intraarterial, pulmonary digital subtraction angiography (DSA) with use of a flow-directed, balloon-tipped catheter in patients with suspected acute pulmonary embolism (PE).


MATERIALS AND METHODS
Pulmonary DSA was performed in 211 patients with suspected PE. Subselective magnification series were obtained with nonionic contrast material. Clinical outcome of patients with a negative pulmonary DSA study was assessed by means of retrospective analysis of their medical records, with a minimum follow-up of 3 months.


RESULTS
Among the 211 patients, DSA image quality was excellent in 129 (61.1%), adequate in 79 (37.4%), and poor in three (1.4%). Two angiograms (0.9%) were nondiagnostic. No complications occurred. Of 129 patients with negative DSA in whom anticoagulants were withheld, 16 died of disorders other than PE; one (0.9%, 95% confidence interval 0.0%, 4.2%) of 113 patients alive at 3 months returned after 3 weeks with possible PE.


CONCLUSION
Pulmonary DSA with the flow-directed catheter is a safe procedure and provides good to excellent image quality. Anticoagulants can be withheld in patients suspected of having PE when pulmonary DSA results are negative.