Division of Vascular Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
Cardiovasc Intervent Radiol. 2012 Apr;35(2):263-7. doi: 10.1007/s00270-011-0149-3. Epub 2011 Mar 24.
Late stent fatigue is a known complication after carotid artery stenting (CAS) for cervical carotid occlusive disease. The purpose of this study was to determine the prevalence and clinical significance of carotid stent fractures.
A single-center retrospective review of 253 carotid bifurcation lesions treated with CAS and mechanical embolic protection from April 2001 to December 2009 was performed. Stent integrity was analyzed by two independent observers using multiplanar cervical plain radiographs with fractures classified into the following types: type I = single strut fracture; type II = multiple strut fractures; type III = transverse fracture; and type IV = transverse fracture with dislocation. Mean follow-up was 32 months.
Follow-up imaging was completed on 106 self-expanding nitinol stents (26 closed-cell and 80 open-cell stents). Eight fractures (7.5%) were detected (type I n = 1, type II n = 6, and type III n = 1). Seven fractures were found in open-cell stents (Precise n = 3, ViVEXX n = 2, and Acculink n = 2), and 1 fracture was found in a closed-cell stent (Xact n = 1) (p = 0.67). Only a previous history of external beam neck irradiation was associated with fractures (p = 0.048). No associated clinical sequelae were observed among the patients with fractures, and only 1 patient had an associated significant restenosis (≥ 80%) requiring reintervention.
Late stent fatigue after CAS is an uncommon event and rarely clinically relevant. Although cell design does not appear to influence the occurrence of fractures, lesion characteristics may be associated risk factors.
颈动脉支架置入术（CAS）治疗颈内动脉闭塞性疾病后，晚期支架疲劳是一种已知的并发症。本研究旨在确定颈动脉支架骨折的发生率和临床意义。
对 2001 年 4 月至 2009 年 12 月期间采用 CAS 和机械栓塞保护治疗的 253 例颈动脉分叉病变进行了单中心回顾性研究。通过多平面颈椎平片，由 2 位独立观察者分析支架的完整性，将骨折分为以下类型：I 型=单个支柱骨折；II 型=多个支柱骨折；III 型=横断骨折；IV 型=横断骨折伴脱位。平均随访时间为 32 个月。
对 106 个自膨式镍钛诺支架（26 个闭孔支架和 80 个开孔支架）进行了随访影像学检查。发现 8 例（7.5%）骨折（I 型 n = 1，II 型 n = 6，III 型 n = 1）。7 例骨折发生在开孔支架中（Precise n = 3，ViVEXX n = 2，Acculink n = 2），1 例骨折发生在闭孔支架中（Xact n = 1）（p = 0.67）。只有既往颈部外照射史与骨折有关（p = 0.048）。骨折患者无相关临床后遗症，仅 1 例患者出现相关严重再狭窄（≥80%）需要再次介入治疗。
CAS 后晚期支架疲劳是一种罕见的事件，且很少具有临床相关性。尽管支架的设计似乎不影响骨折的发生，但病变特征可能是相关的危险因素。
