Angiographic follow-up after carotid artery stenting of bifurcation stenosis

Purpose: The purpose of this prospective study was to determine the restenosis grade, the intima hyperplasia and the stent expansion via angiographic follow-up six months after carotid artery stenting. Materials and Methods: In 100 patients, angiographic follow-up was performed 5.9 months (range: 2.9-11.4 months) after carotid artery stenting. The restenosis grade, the intima hyperplasia and the stent expansion were measured by selective angiography of the treated carotid artery. Results: The mean restenosis grade was 16% (range: 0-78%). In 6 of 100 patients (6%), a restenosis grade of > 50% was measured. In 4 patients the restenosis grade was 50-70%. In 2 patients the restenosis grade was > 70%. In 91 of 100 patients (91%), the restenosis was localized in the former area of stenosis of the carotid artery, and in 9 of 100 patients (9%), the restenosis was localized in the cranial stent end. The mean grade of intima hyperplasia was 31% (range: 2-70%). The mean increase in stent expansion at the time of follow-up was 10% (range: 0-59%). No correlation was able to be determined between the grade of stenosis and the grade of restenosis (rho=0,017, range: -0.180-0.213), between the grade of residual stenosis and the grade of restenosis (rho=0,257, range: 0.064-0.431) and between intima hyperplasia and the grade of restenosis (rho=0,476, range: 0.309-0.615). Conclusions: Carotid artery stenting is associated with a low incidence of high-grade restenosis 6 months after an intervention. The intima hyperplasia, which can be observed in each Wallstent, is partly compensated by the expansion of the self-expandable stent. Without a correlation between the grade of residual stenosis and the grade of restenosis, low-grade residual stenosis can be accepted. Therefore, we recommend undersized postdilation of the Wallstent.