Intravascular Ultrasound in Venous Thoracic Outlet Syndrome.

Background: Venous thoracic outlet syndrome (vTOS) is a rare disease with no defined guidelines regarding treatment. Patients with first rib resection with anterior scalenectomy (FRRS) often have residual subclavian vein stenosis. The aim of this study was to evaluate the use of intravascular ultrasound (IVUS) in the treatment of vTOS patients who have been surgically decompressed with FRRS.

Methods: Patients treated with venography after FRRS for vTOS during 2015-2017 were retrospectively reviewed. Patients were included if they received a venogram with IVUS after FRRS. The axillosubclavian vein at the site of the thoracic outlet was imaged using single-plane venography and IVUS. A greater than 50% diameter stenosis on venography or 50% cross-sectional area reduction on IVUS was considered significant and treated with balloon venoplasty.

Results: During the 2-year period, 14 patients underwent 24 upper extremity venograms performed after surgical decompression for vTOS, 18 of which included IVUS. Of the 18 cases with IVUS, 5 (27.8%) stenoses >50% were detected by IVUS, which were not apparent on venography, leading to intervention. IVUS detected a greater degree of stenosis than venography. Seven patients required repeat venograms. Overall, IVUS detected significant venous stenosis in 94.4% of patients compared with 66.7% of patients with venography after FRRS for vTOS.

Conclusions: These results suggest that IVUS detected greater levels of stenosis than venography, leading to more interventions. Just as IVUS being ideal for identifying occult iliac venous lesions, it may have a similar role in identifying venous lesions not evident on single-plane venography for postsurgical decompression in vTOS patients. Further studies may show this technique to increase the number of stenoses identified and improve long-term symptom relief.