Hemodialysis access dysfunction caused by heavily calcified subclavian artery chronic total occlusion: Two cases treated with balloon-expandable covered stents

Proximal arterial inflow lesions are an underrecognized cause of hemodialysis access dysfunction, particularly in patients with advanced arterial calcification. We report two hemodialysis patients with access dysfunction associated with heavily calcified left subclavian artery chronic total occlusion. Both patients lacked upper-limb claudication or neurological symptoms. Endovascular recanalization was achieved using balloon-expandable covered stents (Viabahn VBX) while preserving the vertebral artery origin. In the first patient, brachial artery flow increased from 55 to 731 mL/min. In the second, flow increased from 275 to 339 mL/min after subclavian revascularization and to 1090 mL/min after subsequent angioplasty of residual fistula stenosis. No procedure-related adverse events occurred, and both accesses remained functional during follow-up. Subclavian artery occlusion should be considered in otherwise unexplained access dysfunction. Balloon-expandable covered stents may provide a useful reconstruction option for heavily calcified proximal inflow lesions.