Side-distribution of in-stent restenosis and its prognosis after stent angioplasty at vertebral artery origin

Objective To investigate the correlation between the in-stent restenosis (IRS) and dominant blood supply side of this vertebral artery and its prognosis after stent angioplasty at vertebral artery origin in patients with cerebral ischemia. Methods A total of 52 patients treated with stent angioplasty at vertebral artery origin were collected from January 2008 to December 2013, and 54 balloon-expanding stents were implanted. The mean followed up time of the patients was 8.5 months after surgery. The correlation between IRS and the sides of diseased vertebral arteries and their prognosis were analyzed retrospectively. Results The symptoms were improved in most patients after implantation of 54 stents. In the vertebral arteries of performing stent angioplasty, the diameters of normal arteries of the stent distal ends of the dominant blood supply (19 branches), the balance blood supply arteries (5 branches), and non-dominant blood supply sides (30 branches) were 4.78±0.86 mm, 4.05±0.67 mm, and 3.27±0.59 mm, respectively (P<0.01). IRS occurred in 13 stents, and they were all on the non-dominant blood supply sides (24.1%). The incidence of IRS on the non-dominance blood supply sides was 43% (13/30 branches). The preoperative and postoperative stenosis rates were 72.5±8.2% and 12.3±9.7% respectively in 13 lesions, the follow-up stenosis rate was 78.7±15.5%, and 2 of them had complete in-stent occlusion. After in-stent balloon dilatation, the follow-up stenosis rate was 25.7±6.1%. Conclusion The non-dominance blood supply side is more prone to IRS after stent angioplasty at vertebral artery origin. The prognosis is better for patients with IRS after balloon re-dilatation. Key words: Stent; In-stent restenosis; Vertebral artery origin; Hemodynamics