Scientific evidence demonstrating the safety of carotid angioplasty and stenting: do we have enough to draw conclusions yet?

Endovascular treatment for restenosis of carotid venous bypass graft: a clinical case report

BACKGROUND AND AIM

Restenosis after open carotid surgery (OCS) represents an issue that experts are very often facing nowadays, both after carotid endoarterectomy(CEA) and carotid bypass(CB). Yet, even if from one side carotid artery stenting (CAS) is currently recommended by most guidelines as treatment of choice for carotid restenosis after CEA, on the other side little is known regarding the best treatment of restenosis after CB. This clinical case report is aimed to empathize the endovascular treatment as an effective therapeutic option for restenosis after OCS.

METHODS

A 75-year-old woman with severe comorbidities was admitted to our Unit for left carotid bypass graft restenosis. One year earlier, the patient had been treated with left carotid bypass grafting in saphenous vein for infectious complications occurred after CEA for symptomatic left carotid stenosis. The patient underwent a carotid Duplex ultrasonography scan (DUS) which showed a hemodynamically significant left carotid venous graft stenosis with peak systolic velocity of 315 cm/sec; in order to assess the grade of the stenosis a computed tomography angiography confirmed the presence of a significant narrowing of left carotid graft. A carotid artery angiography was performed after 20days, reconfirming the presence of a significant left carotid graft stenosis and was successfully treated with 7x40mm self-expanding stent.

RESULTS

The patient had an uneventful post-procedural course and was discharged the day after. After six months, the patient underwent a carotid DUS in our outpatient clinic which confirmed the overall graft and stent patency.

CONCLUSION

CAS represents a feasible therapeutic option for carotid restenosis in patients treated after CB. This clinical case demonstrates that CAS can be performed with acceptable risks and good early results.

Prosthetic bypass for restenosis after endarterectomy or stenting of the carotid artery

OBJECTIVE

The objective of this study was to evaluate the results of prosthetic carotid bypass (PCB) with polytetrafluoroethylene (PTFE) grafts as an alternative to carotid endarterectomy (CEA) in treatment of restenosis after CEA or carotid artery stenting (CAS).

METHODS

From January 2000 to December 2014, 66 patients (57 men and 9 women; mean age, 71 years) presenting with recurrent carotid artery stenosis ≥70% (North American Symptomatic Carotid Endarterectomy Trial [NASCET] criteria) were enrolled in a prospective study in three centers. The study was approved by an Institutional Review Board. Informed consent was obtained from all patients. During the same period, a total of 4321 CEAs were completed in the three centers. In these 66 patients, the primary treatment of the initial carotid artery stenosis was CEA in 57 patients (86%) and CAS in nine patients (14%). The median delay between primary and redo revascularization was 32 months. Carotid restenosis was symptomatic in 38 patients (58%) with transient ischemic attack (n = 20) or stroke (n = 18). In this series, all patients received statins; 28 patients (42%) received dual antiplatelet therapy, and 38 patients (58%) received single antiplatelet therapy. All PCBs were performed under general anesthesia. No shunt was used in this series. Nasal intubation to improve distal control of the internal carotid artery was performed in 33 patients (50%), including those with intrastent restenosis. A PTFE graft of 6 or 7 mm in diameter was used in 6 and 60 patients, respectively. Distal anastomosis was end to end in 22 patients and end to side with a clip distal to the atherosclerotic lesions in 44 patients. Completion angiography was performed in all cases. The patients were discharged under statin and antiplatelet treatment. After discharge, all of the patients underwent clinical and Doppler ultrasound follow-up every 6 months. Median length of follow-up was 5 years.

RESULTS

No patient died, sustained a stroke, or presented with a cervical hematoma during the postoperative period. One transient facial nerve palsy and two transient recurrent nerve palsies occurred. Two late strokes in relation to two PCB occlusions occurred at 2 years and 4 years; no other graft stenosis or infection was observed. At 5 years, overall actuarial survival was 81% ± 7%, and the actuarial stroke-free rate was 93% ± 2%. There were no fatal strokes.

CONCLUSIONS

PCB with PTFE grafts is a safe and durable alternative to CEA in patients with carotid restenosis after CEA or CAS in situations in which CEA is deemed either hazardous or inadvisable.

Carotid restenosis after endarterectomy and stenting: a critical issue?

BACKGROUND

Carotid artery stenting (CAS) is currently considered a valid alternative to carotid endarterectomy (CEA) for the prevention of stroke in high-risk patients. One of the most important issues for both of these techniques is carotid restenosis. The aim of our study was to evaluate the incidence of post-CEA and post-CAS restenosis in a large cohort of patients in a single high-volume center.

METHODS

Between December 2000 and December 2010, 2453 CEA and 2628 CAS procedures were performed in the Vascular and Endovascular Surgery Unit at our institution. The mean age of patients was 73.8 years (range 55‒89 years), 78% of whom were men. Indications for carotid revascularization were: presence of symptomatic carotid artery stenosis of >70%, or asymptomatic stenosis of at least 80%, especially in patients with vulnerable plaques.

RESULTS

Mild and long-term results after CEA and CAS were similar. The overall perioperative neurologic complication rate (minor and major stroke) was similar in the 2 groups. At 1-year follow-up the restenosis rate after CEA was 1.58%. In-stent restenosis after CAS occurred in 1.67% of the procedures. All but 3 arteries had been treated for postsurgical restenosis. All lesions were approached secondarily with endovascular procedures. Statistical analysis demonstrated that post-CEA restenosis was the most important predictive factor for the development of in-stent restenosis after CAS.

CONCLUSIONS

This review of our 10-year experience confirms that patients who develop restenosis after CEA are also prone to developing in-stent restenosis after CAS.

Multicentric retrospective study of endovascular treatment for restenosis after open carotid surgery

OBJECTIVES

To analyse perioperative and midterm outcomes of carotid artery stenting (CAS) for symptomatic >50% and asymptomatic >70% restenosis after open carotid surgery (OCS).

DESIGN

A multicentric retrospective study.

METHODS

Outcome measures 30-day death, neurologic and anatomic (thrombosis, restenosis) events. Univariant and multivariant logistic regression analyses were performed to identify predictive factors for neurologic and anatomic events.

RESULTS

A total of 249 patients with a mean age of 69 years (range, 45-88) were treated for asymptomatic (86%) or symptomatic (14%) restenosis. The 30-day combined operative mortality and stroke morbidity was 2.8% in asymptomatic patients and 2.9% in symptomatic patients. Events during follow-up (mean duration, 29 months) included stroke in four cases, TIA in two, stent thrombosis in four and restenosis in 21. Kaplan-Meier estimates of overall survival, neurologic-event-free survival, anatomic-event-free survival and reintervention-free survival were 95.4%, 94.7%, 96.7% and 99.5%, respectively, at 1 year and 80.3%, 93.8%, 85.1% and 96%, respectively, at 4 years. Multivariant analysis showed that statin use was correlated with a lower risk of anatomic events (odds ratio (OR) = 0.15 (95% confidence interval (CI) 0.03-0.68), p = 0.01) and that bypass was associated with a higher risk of anatomic events than endarterectomy (OR = 5.0 (95% CI 1.6-16.6), p = 0.009).

CONCLUSION

CAS is a feasible therapeutic alternative to OCS for carotid restenosis with acceptable risks in the perioperative period. Restenosis rate may be higher in patients treated after bypass.

Recurrent carotid stenosis after CEA and CAS: diagnosis and management

Carotid endarterectomy (CEA) is the preferred method for cerebral revascularization in patients with symptomatic and asymptomatic high-grade extracranial carotid artery stenosis. Carotid artery stenting (CAS) has recently emerged as a less invasive alternative to endarterectomy. Carotid stenting has been demonstrated to be technically feasible and safe in high-risk patients. It has been approved as an acceptable method for revascularization in circumstances where CEA yields suboptimal results. While the final role of CAS in carotid revascularization will be determined on the basis of ongoing randomized trials, it is clear that stenting will continue to be performed in subgroups of patients with carotid stenosis. Therefore, it is anticipated that there will be a corresponding increase in the number of in-stent restenosis cases. Considerable controversy exists regarding the clinical significance, natural history, threshold for management, and appropriate intervention of recurrent carotid stenosis after endarterectomy and after stenting. This review analyzes current information on this important clinical problem and presents evidence-based recommendations for the diagnosis and management of recurrent carotid stenosis.

Restenosis after carotid endarterectomy: incidence and endovascular management

SUMMARY

Surgical procedures designed to restore vascular patency for a recurrent stenosis following carotid endarterectomy (CEA) are burdened with technical difficulties as well as with the possibility of serious neurological complications. An endovascular approach employing transluminal percutaneous angioplasty and stenting (PTAS) is a promising solution to these problems. We aimed to evaluate the incidence of carotid artery restenosis following CEA, and to evaluate the safety and efficacy of treating post-CEA restenosis with an endovascular technique (PTAS). One hundred and two patients who underwent CEA for symptomatic and asymptomatic stenosis were included in the analysis. Clinical and sonographic follow-up examinations identified carotid artery restenosis in 16 patients, who fulfilled our criteria for endovascular treatment. Carotid PTAS was performed on symptomatic patients with a stenosis over 60% of the artery lumen (n=7) and in asymptomatic patients with a stenosis over 80% (n=9). The post-PTAS patients were evaluated by duplex sonography every three months over a 24 month follow-up period for evidence of restenosis. The cumulative incidence of post-CEA carotid restenosis qualifying for PTAS was 9.3% during an average 12-month follow-up interval. The average time from CEA to carotid PTAS was 11 months. All 16 endovascular procedures were technically successful. All of the carotid arteries were widely patent following PTAS. There were no immediate perioperative complications. One patient died two days after carotid PTAS from a cerebral hemorrhage. Thirteen of the 16 patients remained asymptomatic and had no sonographic evidence of significant restenosis during the 24- month post-PTAS follow-up period. One patient developed a symptomatic 80% restenosis proximal to the stent six months after carotid PTAS. Another patient developed an asymptomatic 60% restenosis proximal to the stent at 24 months. One patient was lost to follow-up. Following CEA, there is a significant risk of developing a symptomatic or high-grade carotid artery restenosis requiring correction. Endovascular treatment (PTAS) of a recurrent stenosis after CEA is a safe and effective alternative to repeat carotid surgery.

Feasibility Trial of Carotid Stenting With and Without an Embolus Protection Device

PURPOSE

To evaluate the feasibility of stenting and cerebral protection in patients with carotid bifurcation disease.

METHODS

Carotid stenting with self-expanding nitinol stents was evaluated in 261 patients (157 men; mean age 70.9+/-9.7 years, range 41-90) treated at 33 clinical sites. Among these patients, 141 (54.3%) were symptomatic, and 71 (27.2%) had postendarterectomy restenotic lesions. An embolus protection device became available in the latter third of the study. The primary endpoint of the study was the 30-day composite occurrence of major adverse clinical events (all deaths, strokes, or myocardial infarctions [MI]). At 1 year, the endpoint included all deaths, strokes, or MIs at 30 days, plus all deaths or ipsilateral strokes between 31 days and 1 year.

RESULTS

SMART stents were placed in 147 (56%) patients and Precise stents in 107 (41%); 7 (3%) patients were treated with non-study stents. Lesion success, defined as <30% postprocedural residual stenosis, was achieved in 249 (95%). An AngioGuard filter was used in 85 patients; of 90 filters employed, 78 (87%) were successfully deployed and retrieved. Visible material was noted in 42 (54%) retrieved filters. One (0.4%) stent thrombosis occurred at <30 days, and no restenotic lesions >80% were noted in up to 1 year of follow-up. At 30 days, stroke occurred in 16 (6.1%) patients, MI in 1 (0.4%), and 2 (0.8%) patients died. The 30-day rate of stroke, MI, or death was 6.9%. Major ipsilateral stroke occurred in 4 (1.5%) patients between 0 and 30 days; no new major ipsilateral strokes were noted up to 1 year. By Kaplan-Meier analysis, the 1-year risk of stroke, MI, or death was 10.9%+/-2.0%. The 1-year risk of major ipsilateral stroke was significantly lower in patients treated with embolus protection devices (0.0% versus 2.3%, p=0.05).

CONCLUSIONS

The use of nitinol self-expanding stents in the carotid position appears to be a safe and efficacious alternative for the treatment of carotid bifurcation disease. The addition of embolus protection devices may diminish the risk of postprocedural major ipsilateral strokes.

Reconstructive surgery of the extracranial arteries

The first carotid endarterectomy (CEA) is usually accredited to Eastcott who reported in 1954 the successful incision of a diseased carotid bulb with end-to-end anastomosis of the internal carotid artery (ICA) to the common carotid artery (CCA). During the following years surgeons were quick to adopt and improve the intuitively attractive procedure. But by the early to mid 1980s several leading neurologists began to question the growing number of CEAs performed at that time. Six major CEA trials were then designed which are now completed or nearing completion. Most conclusive data are available from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) for symptomatic carotid disease, and from the Asymptomatic Carotid Atherosclerosis Study (ACAS) for asymptomatic carotid disease. The key result of these studies is that CEA is beneficial to high grade symptomatic and asymptomatic carotid stenosis. While the benefit in symptomatic disease is clear, it may be negligible in asymptomatic patients suffering from other medical conditions, the most important being coronary artery disease. Since the conclusions from the different studies vary significantly, guidelines and recommendations with regard to CEA have been issued by a number of interest groups, so-called consensus conferences. The best known guidelines are published by the American Heart Association (AHA). However, the practice of interest groups to issue guidelines is currently being criticized, the main reason being that interest groups have different ideas and all claim the right to issue guidelines. At present we recommend CEA for symptomatic high-grade stenosis in patients without significant coincident disease. With regard to asymptomatic stenosis we suggest surgery to otherwise healthy patients if the stenosis is very narrow or progressive. Preoperative evaluation has changed over the years. Currently we recommend duplex sonography in combination with intra- and extracranial magnetic resonance angiography (MRA). Concurrent coronary artery disease is a major consideration in the perioperative management, and the use of a specific algorithm is recommended. Surgery is performed under general anaesthesia with intraoperative monitoring such as electroencephalography (EEG) and transcranial Doppler (TCD). A temporary intraluminal shunt is used selectively if after cross-clamping the flow velocity in the middle cerebral artery (MCA) falls to below 30 to 40% of baseline. For years we employed routine barbiturate neuroprotection during cross-clamping. At the present time we use barbiturate selectively, if the flow velocity in the MCA falls to below 30 to 40% of baseline and if the use of a temporary intraluminal shunt is not possible due to difficult anatomic conditions. The reason to abandon systematic barbiturate protection was to accelerate recovery from anaesthesia. Our patients are monitored overnight on the ICU or a surveillance unit. Routine hospitalization after surgery is 5 to 7 days with a control duplex sonography being performed prior to discharge. A number of details with regard to surgical technique and perioperative management are a matter of discussion. Our surgical routine is described here step by step. Such management resulted in 6 major complications among the 402 cases with 4 of cardiopulmonary and 2 of cerebrovascular origin. For the future we can expect the development of percutaneous transluminal techniques competing with standard carotid endarterectomy. At the present time several comparative studies are under way. Irrespective of the technical approach to treat carotid stenosis, several other issues have to be clarified before long. One of the major unresolved items is the timing of treatment after completed stroke. In this regard prospective trials need to be performed. Although numerically not as important as carotid stenosis, vertebral artery (VA) and subclavian artery (SA) stenoses are more and more accepted as indication for surgical

The ICAROS registry of carotid artery stenting. Imaging in Carotid Angioplasties and Risk of Stroke

ICAROS (Imaging in Carotid Angioplasties and Risk Of Stroke) is a multicenter international registry of carotid artery stenting designed to determine the criteria for identifying patients at higher or lower risk of periprocedural stroke and restenosis at 1 year. The aim of the registry is to improve patient selection and consequently reduce the risk of cerebral embolization during carotid stenting. The registry is open to all interventionists performing carotid stenting, and the participants are free to apply their own endovascular techniques and devices, including cerebral protection mechanisms. All cerebral ischemic events following the procedure will be reported. Follow-up surveillance to 1 year will include periodic duplex scanning and neurological examinations. Echographic plaque images will be standardized for comparison, processed for echodensity, and analyzed by computer at the Registry Center. Correlation will be investigated between the echographic index (gray-scale median) and the risk of embolism and outcome of carotid stenting.

Cerebrovascular angioplasty and stenting for the prevention of stroke

Until recently, stroke preventive strategies have focused on either medical regimens aimed at antagonizing or reversing atherosclerosis, or surgical intervention for revascularization of the cerebrovascular system. However, with the advent of rapidly emerging microcatheterization techniques and technology, endovascular surgical revascularization of the brain is rapidly emerging as a powerful therapeutic modality. In particular, significant advances already have been made in revascularization of the extracranial carotid artery and many common anatomic sites of intracranial athero-occlusive disease, using special adaptations of conventional percutaneous angioplasty and stenting techniques. This paper reviews the cumulative experience with these emerging techniques, with a particular emphasis on clinical outcomes and future directions. It also reports the substantial cumulative institutional experience of the authors over the past 18 months with both extracranial carotid and intracranial artery stent-assisted carotid angioplasty.

Carotid artery stent placement for atherosclerotic disease: rationale, technique, and current status

Carotid arterial endarterectomy is considered to be the standard for the treatment of atherosclerotic carotid arterial occlusive disease. This has been validated with results of several randomized controlled trials in which its effectiveness has been demonstrated over that of the best nonsurgical therapy. In the past several years, however, carotid angioplasty with stent placement has emerged as a potential alternative to carotid endarterectomy. This article represents a critical examination of the rationale for carotid revascularization; the history of endovascular techniques for the treatment of carotid atherosclerosis, beginning with balloon angioplasty and evolving to the use of stents; and the evidence supporting the effectiveness of the endovascular approach. A brief description of the current technical aspects of carotid artery stent placement is presented. The future status of the endovascular approach will be determined with randomized trials in which carotid artery stent placement is directly compared with endarterectomy, as well as by the potential for further innovation and improvement in endovascular devices, technique, and safety.

Systematic comparison of the early outcome of angioplasty and endarterectomy for symptomatic carotid artery disease

BACKGROUND AND PURPOSE

Endoluminal treatment is being increasingly used for carotid artery disease. The aim of this study was to compare the stroke and death risk within 30 days of endovascular treatment or endarterectomy for symptomatic carotid artery disease.

METHODS

systematic comparison of the 30-day outcome of angioplasty with or without stenting and endarterectomy for symptomatic carotid artery disease reported in single-center studies, published since 1990, was performed.

RESULTS

Thirty-three studies (13 angioplasty and 20 carotid endarterectomy) were included in this analysis. Carotid stents were deployed in 44% of angioplasty patients. Mortality within 30 days of angioplasty was 0.8% compared with 1.2% after endarterectomy (OR 0.68, 95% CI 0.43 to 1.05; P=0.6). The stroke rate was 7.1% for angioplasty and 3.3% for endarterectomy (OR 2.22, CI 1.62 to 3.04; P<0.001), while the risk of fatal or disabling stroke was 3.2% and 1.6%, respectively (OR 2.09, CI 1.3 to 3.33; P<0.01). The risk of stroke or death was 7.8% for angioplasty and 4% for endarterectomy (OR 2.02, CI 1.49 to 2.75; P<0.001), while disabling stroke or death was 3.9% after angioplasty and 2.2% after endarterectomy (OR 1.86, CI 1.22 to 2.84; P<0.01).

CONCLUSIONS

In the treatment of symptomatic carotid artery disease, the risk of stroke is significantly greater with angioplasty than carotid endarterectomy. At present, carotid angioplasty is not recommended for the majority of patients with symptomatic carotid artery disease.

Estimating the contemporary in-hospital costs of carotid endarterectomy

Carotid endarterectomy (CEA) is the treatment of choice for symptomatic carotid stenosis and selective asymptomatic lesions. Alternative approaches have recently been championed under the guise of increased efficacy and decreased cost. The purpose of this study was to determine the results and in-hospital costs of CEA in a university hospital in the modern era. A retrospective chart review was undertaken for all patients undergoing CEA between January 1995 and December 1997. This corresponded to the implementation of a clinical path and extended efforts toward cost reduction. Patients undergoing combined CEA and cardiopulmonary bypass were excluded (n = 3). Cost was analyzed by the hospital Office of Program Planning using TSI (Transition Systems, Inc.) software. Direct costs are related to the utilization of clinical resources and are therefore manageable by clinicians (bed, room, supplies, nursing staff, OR staff, radiology, pharmacy, etc.). Total costs additionally include administration and overhead costs not directly chargeable to patient accounts. The results of this study showed that CEA can be safely performed with brief hospital stays and reasonable hospital costs. Results of alternative interventions for the treatment of carotid stenosis should be compared to these contemporary data.

Treatment of carotid tandem stenosis by combined carotid endarterectomy and balloon angioplasty: technical case report

OBJECTIVE AND IMPORTANCE

Cervical internal carotid artery disease associated with high-grade carotid siphon stenosis poses a therapeutic challenge. This report describes the combination therapy of carotid end-arterectomy and intraoperative transluminal balloon angioplasty of the carotid siphon.

CLINICAL PRESENTATION

A 67-year-old man sustained repeated left hemispheric and retinal transient ischemic attacks. Results of a diagnostic examination, including angiography, disclosed a 70% ulcerative stenosis of the left extracranial internal carotid artery as well as a 90% stenosis of the left intracavernous carotid artery. The decision was made for combined open and endovascular therapy.

INTERVENTION

After standard endarterectomy, an introducer for the dilation catheter was placed into the common carotid artery before final closure of the arteriotomy and recirculation. Under intraoperative fluoroscopy, a 3-mm dilation balloon was navigated into the carotid siphon stenosis and inflated several times. A 30% residual stenosis in the carotid siphon was obtained as a final result. The intervention was completed without complications. No further neurological symptoms were observed during the follow-up period of 30 months.

CONCLUSION

Carotid endarterectomy, combined with intraoperative transluminal angioplasty of carotid siphon stenosis, is a feasible procedure for selected patients with carotid tandem stenosis.

Carotid restenosis: operative and endovascular management

PURPOSE

Surgical management of carotid restenosis (CR) after carotid endarterectomy (CEA) has been associated with a higher perioperative complication rate than that of primary CEA. We recently used carotid angioplasty-stenting (CAS) as an alternative to operative management in patients who had undergone CEA within three years, and we retrospectively compared these results with those of operative management of CR and the overall results of CEA.

METHODS

CEA was performed on 1065 adult patients (58% symptomatic, 42% asymptomatic), 62% of whom were men (n = 660) and 38% of whom were women (n = 405), from 1989 to 1997. Before our initiation of a program of CAS, 16 operative procedures (1.9% of CEAs) were performed for CR in 14 adult patients (7 women and 7 men). During the last 20 months, CAS was used in the management of 17 CRs (16 patients; 9 women and 7 men).

RESULTS

The 30-day stroke morbidity-death rate for all CEAs (n = 1065) was 1.4%; 11 strokes (1. 0%) occurred (4 major strokes with disability and 7 strokes with minor or no disability), and 4 deaths (0.4%) occurred (2 deaths caused by myocardial infarction, 1 caused by intracranial hemorrhage, and 1 caused by stroke). Operative management of CR (n = 16) included patch angioplasty in 12 cases (autologous vein patches in 10 cases and synthetic patches in 2 cases), whereas interposition grafting was used in 4 cases (saphenous vein in 3 instances and synthetic [polytetrafluoroethylene] in one case). No strokes or deaths were observed. One recurrent laryngeal nerve palsy occurred (6.2%). Among the 16 patients undergoing 17 CAS procedures, the technical procedures were accomplished in all patients. No strokes or deaths occurred. No recurrent restenoses (50% or greater) have been identified within or adjacent to the CAS procedures.

CONCLUSION

CR caused by myointimal hyperplasia can be managed by operative techniques or CAS with comparable periprocedural complications. Although long-term follow-up will be required to determine the incidence of recurrent restenosis, CAS may become the preferred procedure in these cases. A randomized clinical trial ultimately will be necessary to determine the role of CAS, as compared with that of operative management.