OBJECTIVE: To investigate the effect and safety of transradial stent angioplasty using double guide wires for severe stenosis of vertebral artery ostium at a lower location. METHODS: Patients with severe stenosis of the vertebral artery ostium at a lower location treated with transradial stent angioplasty were retrospectively enrolled. All the clinical and endovascular treatment data were analyzed. RESULTS: Thirty-nine patients were enrolled. A low location of the vertebral artery ostium was present in 33 (84.6%) patients and an ultra-low location in 6 (15.4%). Transradial stent angioplasty was performed in all patients. In one patient who had a tortuous radial artery, the transradial access was failed. In the other 38 (97.4%) patients, transradial stent angioplasty was all successful. The sharp angle formed between the vertebral artery and the subclavian artery was significantly (P <
0.0001) increased from 15° to 65° (36° ± 11°) before to 70-125° (90° ± 17°) after insertion of a support guide wire. No damage was found in all support guide wires. Thirty-nine stents were deployed, and the preoperative stenosis rate of 70%-98% (85% ± 13%) was significantly (P <
0.0001) decreased to 0-25% (16%) immediately after stenting. Six-12 months after surgery, 29 (74.4% or 29/39) patients were followed up with imaging, and 9 (31.0%) patients experienced in-stent restenosis, with endovascular retreatment being performed in 3 (33.3%) patients. CONCLUSIONS: Transradial stent angioplasty using double guide wires is safe and effective for the treatment of severe stenosis of the vertebral artery ostium at a lower location even though more studies are necessary to confirm this.