Carotid artery stenting - current status of the procedure

Risk Factors for Recurrent Carotid-Artery Stenosis Following Stenting Treatment

BACKGROUND Carotid artery stenting (CAS) has been regarded as a reliable treatment approach for carotid artery stenosis. However, recurrent carotid artery stenosis after CAS affects long-term outcomes. In this study, we aimed to investigate the potential risk factors for carotid restenosis. MATERIAL AND METHODS We retrospectively analyzed the clinical data of patients diagnosed with carotid artery stenosis who underwent CAS implantation at our department from September 2012 to July 2015. Each included study patient was followed up with serial duplex ultrasound scanning. Kaplan-Meier estimates were used to evaluate freedom from restenosis and potential risk factors were analyzed. RESULTS There were 33 patients enrolled in our study. The mean age was 65.5±11.5 years. The technique was successfully achieved in all patients. No death or major stroke occurred after stenting. There were 2 events of minor stroke and one myocardial infarction within 30 days after stent implantation. All the patients were followed up for 3 years. Cumulative rates of freedom from recurrent stenosis at 1, 2, and 3 years were 87.4%, 74.6%, and 68.3% respectively. Cox multivariate regression analysis revealed that male sex, smoking and hyperlipidemia were independent risk factors associated with restenosis. CONCLUSIONS In this study, we identified that CAS was a reliable approach for carotid artery stenosis. Male sex, smoking, and hyperlipidemia were independent risk factors associated with restenosis. Thus, hyperlipidemia should be monitored and routine follow-up with ultrasonography are recommended especially for male patients with current or history of smoking.

[An efficacy of carotid arteries repair for tortuosity combined with stenosis]

AIM

To assess an efficacy of carotid arteries reconstruction in patients with internal carotid artery stenosis combined with tortuosity.

MATERIAL AND METHODS

86 patients with ICA tortuosity and stenosis were enrolled. All patients were divided into groups depending on type of surgery: group I - open carotid endarterectomy (CEA) followed by obligatory repair with synthetic patch (31 (36%) patients); group II - eversion CEA with ICA resection, redressation and reimplantation into own ostium (35 (40.7%) patients); group III - ICA replacement (20 (23.3%) patients). Synthetic prosthesis and autovein were used in 13 (65%) and 7 (35%) patients respectively. The study included patients with ICA stenosis ≥60% (any type of plaque) and any degree of cerebrovascular insufficiency or ICA stenosis <60% (plaque type I-III) with CVI grade II-IV combined with S- or C-tortuosity, bend or loop with blood flow velocity over 110 cm/s and its turbulence. Only 6 (7.0%) out of 86 patients had no clinical signs of CVI/previous stroke. Asymptomatic/symptomatic patients ratio was following in all groups: group I - 12 (38.7%)/19 (61.3%); group II - 29 (82.9%)/6 (17.1%); group III - 10 (50%)/10 (50%).

RESULTS

Within 6-month follow-up 22 (70.9%) out of 31 patients were asymptomatic in group I, 30 (85.7%) (p=0.9475) out of 35 - in group II, 9 (45%) (p=0.9511) out of 20 patients - in group III and 1 (5%) patient developed thrombosis of the reconstruction zone followed by ischemic stroke. After 12 months following patients were asymptomatic: 22 (70.9%) in group I, 30 (85.7%) (p=0.9475) in group II and 9 (45%) patients (p=0.9511) in group III. After 1 year 4 (33.3%) out of 12 patients with CVI grade IV had partial regression of focal neurological symptoms.

CONCLUSION

Surgery for ICA tortuosity combined with stenosis confirmed its efficacy and safety for both asymptomatic and symptomatic patients. Significantly better results were observed in eversion CEA compared with conventional procedure and ICA replacement.

Risk of developing open-angle glaucoma in patients with carotid artery stenosis: A nationwide cohort study

Whether carotid artery stenosis (CAS) is an independent risk factor for open-angle glaucoma remains unclear. In this study, we investigated the association between CAS and the development of open-angle glaucoma in the Taiwanese population-based cohort derived from a longitudinal database containing claims data from the Taiwan National Health Insurance (NHI) program; this study enrolled 2093 patients with CAS and 8372 patients without CAS matched by age and sex from 1999 to 2010. Diagnoses of open-angle glaucoma (OAG) were identified during a follow-up period lasting through December 31, 2013. A Cox proportional hazards model was applied to evaluate the hazard ratio (HR) for OAG in the CAS cohort compared with the matched cohort. We found that the HR for open-angle glaucoma in the CAS cohort compared with the matched cohort. The adjusted HR for OAG in the CAS cohort was 1.50 (95% confidence interval, 1.11-2.02, P = .008). The Kaplan-Meier analysis revealed that the CAS cohort had a higher cumulative incidence of OAG than did the matched cohort during the follow-up period (log-rank test, P < .001). We concluded that CAS is a significantly independent risk factor for the development of OAG. Our finding is clinically important for the aging population, which has an increasing prevalence of CAS.

Impact of coexisting multivessel coronary artery disease on short-term outcomes and long-term survival of patients treated with carotid stenting

INTRODUCTION

Systemic atherosclerosis can result in both coronary artery disease (CAD) and carotid artery disease. Recently it has been shown that patients with CAD have a higher incidence of microembolization during carotid artery stenting (CAS), and it has been hypothesized that they could be at higher risk in this intervention.

MATERIAL AND METHODS

We retrospectively evaluated an institutional registry with 437 consecutive patients who underwent coronary angiography and CAS to evaluate their short-term outcomes and long-term survival with regard to the presence of coexisting multivessel coronary artery disease (MVD).

RESULTS

We performed 220 CAS procedures in MVD patients and 318 CAS procedures in non-MVD patients. The incidence of in-hospital CAS-related adverse events was 2.7% and 2.5% in the MVD and non-MVD groups, respectively (p = 0.88). At 30 days, there was no significant difference between the groups in terms of the number of patients with adverse events (hierarchically death/stroke/myocardial infarction; 8.8% vs. 5.5%; p = 0.18). The median duration of follow-up was 4.23 years. Survival free of all-cause mortality at 1, 3 and 5 years was 90% (95% CI: 86-94%), 79% (95% CI: 73-85%) and 70% (95% CI: 64-77%), and 92% (95% CI: 89-95%), 85% (95% CI: 80-90%) and 76% (95% CI: 70-82%) for the MVD and non-MVD groups (p = 0.02), respectively.

CONCLUSIONS

These results suggest that patients with MVD combined with carotid artery disease are probably not at higher risk of early post-CAS adverse clinical events, but they have significantly worse long-term survival rates.

Carotid stenting versus endarterectomy for the treatment of carotid artery stenosis: Contemporary results from a large single center study

OBJECTIVE

To compare the complication rates associated with carotid endarterectomy (CEA) versus carotid artery stenting (CAS).

BACKGROUND

Carotid stenosis is a well-known cause of stroke and increased mortality. The safety of carotid revascularization may be related to symptom status, medical comorbidities, use of embolic protection devices, as well as operator experience and these factors may vary across patient populations within a single operating center.

METHODS

We retrospectively analyzed patients with carotid artery stenosis admitted to our hospital for carotid revascularization between January 1, 2007 and December 1, 2013. The primary end point was a composite endpoint of periprocedural death, stroke, and myocardial infarction (MI).

RESULTS

Of the 718 patients admitted for carotid revascularization 525 (73.1%) underwent CEA and 193 (26.9%) underwent CAS. Both groups demonstrated similar rates of the composite endpoint, MI, and death; the stenting group demonstrated a higher rate of stroke (4.2% vs. 1.3%; P = 0.020). Adjusting for baseline medical comorbidities and symptom status mitigated this difference (P = 0.091 and 0.113, respectively). When stratified by department performing CAS, there was a significant difference in the occurrence of stroke (P = 0.033), which likewise disappeared in the multivariate regression analysis.

CONCLUSION

The risk of the composite endpoint did not differ significantly between those undergoing CAS versus CEA. The stenting group demonstrated a higher rate of periprocedural stroke, which was also apparent when patients were stratified by stenting department. These differences were likely driven by variation in baseline medical comorbidities and symptom status. © 2016 Wiley Periodicals, Inc.

Evaluation of cerebrovascular reserve in patients undergoing carotid artery stenting and its usefulness in predicting significant hemodynamic changes during temporary carotid occlusion

We investigated the usefulness of cerebrovascular reserve (CVR) testing to predict severe hemodynamic changes during proximally protected carotid artery stenting. Of 90 patients referred, 63 eligible underwent complete evaluation of the extent of carotid artery disease and transcranial Doppler ultrasound (TCD) assessment of CVR by means of a breath-holding test and ophthalmic artery flow pattern evaluation. Periprocedural TCD monitoring of the ipsilateral middle cerebral artery flow was performed in 24 patients undergoing proximally protected procedure (requiring induction of flow arrest within internal carotid artery). Abnormal CVR was significantly less common in patients with unilateral compared to bilateral carotid artery disease (26.3 % vs. 76.9 %, p=0.02), while ophthalmic artery flow reversal was rare in patients with unilateral carotid artery disease (2.5 % vs. 42.9 %, p<0.01). During the induction of carotid flow arrest, the average mean flow velocity drop following external carotid artery occlusion was low (3.5 %, p=0.67) compared to the induction of complete flow arrest (32.8 %, p<0.01). Six patients had a total mean flow velocity drop >50 %, including 2 patients with normal pre-procedural CVR. Our results suggest that TCD evaluation of CVR is not a reliable predictor of hemodynamic changes induced during proximally protected carotid artery stenting in patients with unilateral carotid artery disease.

Predicting Hemodynamic Changes of Cerebral Blood Flow during Temporal Carotid Occlusion: A Review of Current Knowledge with Implication for Carotid Artery Stenting

Carotid artery disease (CAD) plays an important role in the stroke development and its prevalence increases with aging of the population. Its wide variability of clinical manifestation ranges from incidental asymptomatic finding to devastating or fatal stroke, although cerebral collateral circulation is considered one of the major modifying factors. Over time, carotid artery stenting (CAS) has evolved into a reputable method for the treatment of patients with severe CAD. With expanding use of proximal protection systems resembling surgical clamp, there is an increasing demand to understand collateral cerebral circulation to protect patients from periprocedural hypoperfusion, which increases the risk of cerebral events. Transcranial Doppler ultrasound (TCD) is a useful tool allowing monitoring in real time during procedure patient́s cerebral hemodynamic status providing the operator with valuable information. Its role in predicting periprocedural hypoperfusion is, however, less well established. In this article, we discuss the role of cerebral collateral circulation, summarize the current knowledge regarding its evaluation with TCD and suggest future implications for CAS.

Intravascular Near-Infrared Spectroscopy: A Possible Tool for Optimizing the Management of Carotid Artery Disease

Stroke is the second most common cause of morbidity and mortality in the Western nations. It is estimated that approximately one-fifth of all strokes or transient ischemic attacks are caused by carotid artery disease. Thus, treatment of carotid artery disease as a mean of stroke prevention is extremely important. Since the introduction of carotid endarterectomy, debate has persisted over the treatment strategy for carotid artery disease. Current recommendations have many potential flaws because they are often based on older trials performed before the introduction of modern pharmacotherapy and are mostly based on the angiographic degree of stenosis, without an emphasis on the pathophysiology of the disease. Most carotid events are caused by rupture or distal embolization of the content of an unstable atherosclerotic plaque with a large lipid pool. Thus, it is plausible that the information regarding the composition of the atherosclerotic plaque could play an important role in deciding on a treatment strategy. In this review article, we provide information about near-infrared spectroscopy, a new invasive imaging modality, which seems to be capable of providing such information.