Carotid Stent Fracture Research Articles

Carotid Stent Durability: The Incidence of Carotid Stent Fracture and the Associated Implications

Carotid Stent Durability: The Incidence of Carotid Stent Fracture and the Associated Implications

Abstract Number ‐ 71: Management of Delayed Carotid Stent Fracture with an Overlapping Open Cell Design Stent: Case Report

Introduction Stent fracture after carotid angioplasty and stenting is rare. Risk factors include presence of angulation, calcification, and restenosis increasing the risk of stent fracture. Although literature indicates that not all carotid stent fractures are associated with adverse outcomes, there is limited details on successful endovascular management of this entity. We describe a unique case of carotid stent fracture with symptomatic restenosis treated with an overlapping open cell stent with no residual stenosis and resolution of symptomology. Methods Case Report. Results A 79‐year‐old man with medical history of right sided symptomatic carotid artery stenosis which had been previously treated with endarterectomy and subsequently carotid stenting after a follow up carotid ultrasound demonstrated recurrence of severe right internal carotid artery (RICA) stenosis. Approximately 2 years after this index procedure, the patient returned with acute onset of left‐hand numbness. Cerebral angiography was performed that demonstrated 85% stenosis with a fractured carotid stent at segment of stenosis (Figure 1A, B). Furthermore, the lesion was found to be heavily calcified. This was determined to be the primary contributing factor in resultant artery wall stress, which over time led to carotid stent fracture. Angioplasty with placement of a new open cell stent and distal embolic protective device was performed successfully. The open cell stent was chosen for this approach as closed cell stents have been associated with an increased odds of in‐hospital stroke/death for carotid lesions, attributable to the lower degree of conformability with closed cell stents. After our stent placement, there was no significant residual stenosis visualized (Figure 1C, D). The patient’s symptoms resolved without any subsequent complaints on follow‐up visit. Conclusions While carotid stent fractures are a rare occurrence, we report a case of symptomatic carotid artery restenosis with a fractured stent due to significant lesion calcification and wall stress. This case was successfully treated with angioplasty and new open cell stent placement due to its potential advantages over closed cell stents in carotid artery lesions. Current literature indicates that carotid stent fractures have a low prevalence. However, there is a paucity of studies on the mechanism of stent fracture as well as optimal management of these fractured stents, suggesting a need for further study and characterization.

Internal carotid artery stent fracture likely caused by hyoid bone compression.

Internal carotid artery stent fracture likely caused by hyoid bone compression.

Carotid Stent Fracture due to Eagle Syndrome after Endovascular Stenting for the Treatment of Acute Ischemic Stroke Caused by Internal Carotid Artery Dissection: Case Report

Carotid Stent Fracture due to Eagle Syndrome after Endovascular Stenting for the Treatment of Acute Ischemic Stroke Caused by Internal Carotid Artery Dissection: Case Report

P.100 Carotid stent fracture post balloon angioplasty for unilateral recurrent ICA stenosis with pre-existing occlusion of contralateral ICA and literature review

Background: Closed cell carotid stent fracture is rare. From our literature review, we present the first reported case in English literature of a carotid stent fracture post angioplasty for an in-stent stenosis. Methods: Case Report Results: 72-year-old male underwent left carotid stenting for symptomatic ulcerated stenosis of the proximal aspect of left ICA (71% stenosis with post-stenting 55% residual stenosis). His right ICA and right vertebral artery were occluded. 2 months later, he presented with TIA’s and severe in-stent stenosis in the proximal left ICA measuring 1 mm in diameter. Satisfactory balloon (5×40 mm) angioplasty was done with residual stenosis measuring 2.5 mm in diameter. 8 months later he presented with symptoms of compromised cerebral perfusion. Workup showed a stent fracture distally at the site of severe ICA stenosis secondary to atherosclerotic calcified plaque causing blood flow changes. His PSV (peak systolic velocity) in the left ICA was 383 m/s. As such he underwent left ICA re-stenting for symptomatic severe left ICA stenosis of 70% with 40% residual stenosis following stent deployment. Conclusions: Carotid stent fracture post balloon angioplasty for recurrent stenosis is rare but of paramount importance. We demonstrate re-stenting as a viable treatment modality when patient profile is not amenable to a surgical revascularization procedure.

Letter to the Editor Fracture of a carotid stent and restenosis of common carotid artery

Letter to the Editor Fracture of a carotid stent and restenosis of common carotid artery

Carotid stent fracture and restenosis management

We report an unusual case of asymptomatic accelerated right carotid artery in-stent restenosis in a patient referred for revascularization of a de novo stenosis of her left internal carotid artery.

Prevalence and clinical significance of stent fracture and deformation following carotid artery stenting

Carotid artery stenting (CAS) is a developing intervention for carotid artery stenosis, and long-term outcomes remain unclear. We examined the prevalence and clinical significance of carotid stent fractures or deformations following CAS. Two hundred thirty-one CAS performed in 219 patients at one academic institution between August 2000 and March 2009 were reviewed. One hundred sixteen stents (57 closed cell, 59 open cell) were evaluated with multiplanar plain films of the neck to assess for stent fracture or deformation. Stent fracture was identified by wire strut disruption. Deformation was defined as an increase in stent-cell area from stent strut distortion. Study endpoints included rate of stent fracture or deformation determined using Kaplan-Meier and life table analysis. Factors associated with stent fracture or deformation were identified by Cox regression. Effect of stent fracture or deformation on recurrent carotid artery stenosis >70% requiring reintervention and postoperative stroke was studied. There were five stent fractures (4%) and 27 deformed stents (23%). Rate of stent fracture or deformation was 15% at 2 years and 50% at 4 years. Deformations were significantly more common in open cell stents than in closed cell stents (58% vs 5% at 4 years, P < .00005). Presence of calcified plaque on plain film was significantly associated with increased rate of stent fracture or deformation (P = .0006). At median follow-up of 25 months, restenosis requiring treatment occurred in four (5%) and late stroke in one (1%). Neither stent fracture nor deformation was associated with late stroke or reintervention. Stent fracture and deformation is not uncommon following CAS and is associated with the presence of heavy calcification. Whether a carotid stent fractures or deforms correlates with stent design. Larger studies are necessary to determine the possible clinical significance of carotid stent fracture and deformation.

Are Carotid Stent Fractures Clinically Significant?

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.

Carotid Stent Fracture with Recurrent High-Grade Stenosis

Stent fracture is a rare complication after carotid angioplasty and stenting. Patient anatomy, stent design, and external forces may all be contributing risk factors. Treatment options include continued observation or reintervention by both endovascular and open techniques since patients are typically asymptomatic. We present a case of a 66-year-old male with carotid stent fracture who developed recurrent, high-grade, asymptomatic carotid artery stenosis that was treated with repeat carotid angioplasty and stenting.

PP11. Prevalence and Clinical Significance of Stent Fracture and Deformation Following Carotid Artery Stenting

Carotid artery stenting (CAS) is a developing intervention for carotid artery stenosis, and the long-term outcomes remain unclear. The purpose of this study was to determine the prevalence of carotid stent fractures or deformations following CAS and the clinical significance of these stent changes.

Carotid stent fracture: Diagnosis and management

With increasing numbers of carotid stent implantations, stent fractures likely will be detected in this vessel region. The authors report two cases of stent fracture: one balloon expandable and one self expandable stent fractured and caused symptoms. CT angiography identified the stent fractures. One partial stent fracture in the internal carotid artery caused a significant restenosis. One complete stent fracture in the common carotid artery caused neurological symptoms, but no significant restenosis. Computerized tomographic angiography (CTA) findings were confirmed by conventional angiography and treated by repeated stent implantation. In a 12-month follow-up period, both patients remained further neurologically asymptomatic and there was no restenosis in duplex sonography or CTA.

Prevalence of Carotid Stent Fractures in a Single-Center Experience

To assess the prevalence of carotid stent fractures and quantify any associated restenosis or clinical events in a single-center experience. Seventy-eight consecutive patients were recorded in a prospective database between 2003 and 2007. Nearly two thirds (51, 65%) were available for follow-up, which included magnified multiplanar radiography and selective duplex ultrasonographic studies to evaluate fracture and restenosis in 53 self-expanding stents (49 open-cell and 4 closed-cell designs). The images were assessed independently by 2 vascular radiologists blinded to the patients' clinical data. There was 1 (1.9%) stent fracture with no associated adverse events or restenosis. Six (11%) stents had an irregular "fish-scale" appearance that was easily confused for fracture and seen only in the open-cell stents. Stent fractures do occur in the carotid artery; however, they are rare and, in our experience, have no clinical sequelae. Radiological assessment should be incorporated into clinical and ultrasound surveillance protocols.

Stenting for carotid artery stenosis: Fractures, proposed etiology and the need for surveillance

Carotid artery stenting is a relatively new intervention for the treatment of carotid artery stenosis, and the long-term outcomes and complications are therefore yet to be determined. In one surgeon's practice, it was found that a stent fracture was the etiological factor for recurrent stenosis. A retrospective study was therefore performed with the hypothesis that carotid stent fractures are common. The aims were to determine prevalence of fractures in this surgeon's series, risk factors, and most importantly, clinical relevance. Patients from one surgeon's private practice who had carotid stenosis deemed suitable for intervention (>80% asymptomatic, >70% symptomatic, 50% to 70% if an ulcerated lesion) and had suitable aortic and carotid morphology for carotid stenting between March 2004 and December 2006 were included. To enhance the quality of the measurement, two vascular surgeons and one radiologist examined the films independently to determine if there was a fracture present. Given that this was a retrospective study, there was no preconceived sample size determined. Fracture prevalence was found to be 29.2% or 14 out of 48 stents. Restenosis occurred in 21% of those stents with a detected fracture, after an average follow-up of 15 months. Several anetiological factors are proposed, with a finding in this series, of a strong and significant association between the presence of calcified vessels and the presence of fractures (odds ratio 7.7; standard error 5.6; 95% confidence interval 1.9-32.0, P =.003). Although this is a small study, it demonstrates that carotid stent fractures do exist, and importantly, not all of them are benign. Therefore, the authors recommend regular surveillance with plain radiography in addition to duplex ultrasonography to enable early detection of fracturing. Following detection, institution of increased surveillance frequency and/or any appropriate intervention can be implemented, to aid in the prevention of complications resulting from restenosis should it become apparent.

Fracture of a carotid stent: An unexpected complication

We present the first reported case of a carotid artery stent fracture where a Nitinol stent was used for the management of carotid artery stenosis. An 83-year-old man underwent right carotid artery stenting in July 2005. On follow-up ultrasound, stenosis of the right internal carotid artery was noted. In January 2006, he underwent left carotid artery stenting and at this procedure, precontrast assessment of the right neck revealed a complete fracture through the waist of the stent in the right internal carotid artery. This fractured segment correlated with the area of stenosis reported at the previous ultrasound. In July 2006, this gentleman underwent successful removal of the carotid stent with uneventful carotid endarterectomy and synthetic patch repair. Carotid artery stenting is a newer and alternative modality to carotid endarterectomy for the treatment of carotid artery stenting. More data are emerging to support its safety and efficacy. An unexpected complication can happen with any procedure and complications help define the follow-up management of subsequent patients undergoing this procedure.