Bronchial artery dilatation on MDCT scans of patients with acute pulmonary embolism: comparison with chronic or recurrent pulmonary embolism

OBJECTIVE: The purpose of our study was to compare the bronchial arteries of patients with acute pulmonary embolism with those of patients with chronic or recurrent pulmonary embolism. MATERIALS AND METHODS: Twenty-seven patients with acute pulmonary embolism and 14 patients with chronic or recurrent pulmonary embolism were retrospectively identified from 700 consecutive patients with suspected pulmonary embolism. The case data for the patients were assessed by two thoracic radiologists whose final judgments were reached by consensus. On the MDCT pulmonary angiograms obtained in these patients, the bronchial arteries were assessed by finding enhancing, small, round or curvilinear structures within the mediastinum and tracing their paths along the bilateral main bronchi. Bronchial arteries with a diameter greater than 1.5 mm were considered to be dilated. RESULTS: The diameters of the bronchial arteries in the group with chronic or recurrent pulmonary embolism were significantly larger than diameters of the bronchial arteries in the group with acute pulmonary embolism (p = 0.0002). Dilatation of bronchial arteries was observed in two of the 27 patients with acute pulmonary embolism and in seven of 14 patients with chronic or recurrent pulmonary embolism. This difference was statistically significant (p = 0.004). No dilated bronchial arteries were seen in patients who had acute pulmonary embolism but had no a history of deep venous thrombosis. CONCLUSION: Acute pulmonary embolism did not appear to cause dilatation of bronchial arteries, whereas chronic or recurrent pulmonary embolism was frequently associated with dilated bronchial arteries. In patients in whom the distinction between acute and chronic or recurrent pulmonary embolism on MDCT pulmonary angiography is clinically unclear and in whom the bronchial arteries are dilated, a diagnosis of chronic or recurrent pulmonary embolism should be favored.