Surgical management of acute carotid thrombosis after carotid stenting: a report of three cases

Importance of cerebral angiography in the evaluation of delayed carotid stent thrombosis: a case report

BACKGROUND

While noninvasive imaging is typically used during the initial assessment of carotid artery disease, digital subtraction angiography remains the gold standard for evaluating carotid stent thrombosis and stenosis (Krawisz in Cardiol Clin 39:539-549, 2021). This case highlights the importance of digital subtraction angiography for assessing carotid artery stent patency in place of non-invasive imaging.

CASE PRESENTATION

We present a 61-year-old African American male patient with a history of right cervical internal carotid artery dissection that was treated with carotid artery stenting and endovascular thrombectomy, who developed recurrent right hemispheric infarcts related to delayed carotid stent thrombosis. Digital subtraction angiography found multiple filling defects consistent with extensive in-stent thrombosis not clearly observed with magnetic resonance angiography. Etiology was likely secondary to chronic antiplatelet noncompliance. Therefore, the patient was treated medically with a heparin drip, and dual antiplatelet therapy (dAPT) was restarted. At 1-month follow-up the patient did not report new motor or sensory deficits.

CONCLUSION

In the setting of delayed carotid stent thrombosis secondary to antiplatelet noncompliance, digital subtraction angiography may play an essential diagnostic role for early identification and determination of the most appropriate treatment.

Revascularization of acute stent thrombosis caused by diarrhea after carotid artery stenting in an intermediate clopidogrel metabolizer

Carotid artery stenting (CAS) is an alternative treatment to carotid endarterectomy for carotid artery stenosis. Acute stent thrombosis (ACST) is an extremely rare complication but can have devastating consequences. Although many cases have been reported, the best treatment is still uncertain. In this study, we report the treatment of ACST caused by diarrhea in an intermediate clopidogrel metabolizer. We also review the literature and discuss appropriate treatment strategies for this rare event.

Rescue of immediate post-transcarotid artery revascularization carotid stent thrombosis due to clopidogrel resistance using flow-reversal and aspiration thrombectomy

An 84-year-old patient developed immediate thrombosis of his carotid stent in recovery after transcarotid artery revascularization. In the present report, the technical details about intraoperative management for neurovascular rescue using the transcarotid artery revascularization flow-reversal system are described. The patient was determined to have clopidogrel resistance. Intraoperative medical management is also discussed. The current alternative intravenous and oral antiplatelet therapies such as glycoprotein IIb/IIIa and P2Y12 inhibitors are explored. The debate regarding preoperative antiplatelet resistance testing remains ambiguous, and increasing studies have demonstrated the safety and efficacy of alternatives to clopidogrel. Despite an unpredictable and devastating complication, the patient's outcome was successful using contemporary strategies.

A Case of Acute In-Stent Mobile Plaque after Carotid Artery Stenting Aspirated with a Distal Access Catheter

Objective

Carotid artery stenting (CAS) is common procedure for carotid stenosis, but sometimes acute in-stent thrombosis or plaque protrusion after CAS leads to postoperative stroke. There are few reports of aspiration of in-stent plaque protrusion. This paper reports a case of acute in-stent mobile plaque aspirated with a distal access catheter.

Case Presentation

A 74-year-old male underwent CAS for symptomatic internal carotid artery stenosis and postoperative course was thought to be good, but in-stent mobile plaque was detected by carotid duplex at postoperative day 6. As mobile plaque is a high risk for stroke, we performed plaque aspiration with a distal access catheter, without neurological deficit or a new cerebral lesion in magnetic resonance imaging. We present a case report, including a literature review, of acute thrombosis or in-stent plaque protrusion.

Conclusion

Aspiration removal may be effective for in-stent mobile plaque, which is expected to be fragile, avoiding the disadvantages of increasing stents.

Carotid endarterectomy for acute carotid thrombosis after carotid artery stenting with CASPER Rx® stent: A case report

Background

Acute carotid stent thrombosis (ACST) is a rare but devastating complication for carotid artery stenting (CAS). That requires early diagnosis and immediate treatment. Although administration of drugs or endovascular treatment is the most widely used approach for patients with ACST, there is no consensus on the standard treatment of this disease.

Case Description

The present study reports on an 80-year-old female patient with the right internal carotid artery stenosis (ICS) that had been followed up by ultrasonography for 8 years. Although the optimal medical treatment was followed, the patient's right ICS worsened, and the patient was subsequently hospitalized for CAS. On the 12^th day after CAS, left paralysis and dysarthria were observed. Head magnetic resonance imaging (MRI) showed acute obstruction of the stent and scattered cerebral infarction in the right cerebral hemisphere caused possibly by the discontinuation of temporary antiplatelet drug therapy as a means to prepare for embolectomy of the femoral artery. Stent removal and carotid endarterectomy (CEA) were selected as the appropriate treatment approach. CEA was performed with the precaution of stent removal and distal embolism, and complete recanalization was obtained. Postoperative head MRI showed no new findings of cerebral infarction, and the patients remained symptom-free after 6 months of postoperative follow-up.

Conclusion

Stent removal with CEA could be an appropriate curative option in some cases with ACST except in patients at high risk of CEA and in the chronic phase after CAS.

Acute carotid stent thrombosis: A case report and literature review

BACKGROUND

Acute carotid stent thrombosis (ACST) is a rare but devastating complication in the carotid artery stenting (CAS) procedure. The aim of this article is to report a case and review cases of ACST reported in the literature, and investigate risk factors and management strategies for ACST.

CASE SUMMARY

We reviewed the treatment process of a patient with ACST after CAS. Then multiple databases were systematically searched to identify studies reporting ACST from 2005 to 2020. The demographic data, risk factors, treatment strategies, and prognosis were extracted and analyzed.

CONCLUSION

The reason for ACST is multifactorial. Proper patient selection, normative anti-platelet treatment, and perfect technical detail may decrease the incidence of ACST. Several treatment strategies such as thrombolysis, mechanical thrombectomy, and open surgery may be options for the treatment of ACST. Limited data have shown that carotid endarterectomy is effective with favorable results.

Carotid endarterectomy with stent removal for recurring in-stent restenosis: A case report and literature review

Background:

Percutaneous transcatheter angioplasty (PTA) and carotid artery stenting (CAS) are often performed repeatedly for in-stent restenosis (ISR) after CAS. Only a few reports describe the treatment for repeated ISR. Furthermore, only a few reports describe carotid endarterectomy (CEA) after CAS; thus, the evidence for this procedure is insufficient.

Case Description:

Herein, we describe a case in which CEA with stent removal was performed in a patient with repeated ISR after CAS. A 78-year-old man presented with dysarthria and slight left limb weakness. CAS was performed for the right internal carotid artery stenosis. ISR occurred again and PTA and stenting were performed. After the second CAS, ISR occurred again. CEA with stent removal was performed. After the CEA with stent removal, the patient experienced no restenosis or other complications.

Conclusion:

CEA with stent removal can be a good option for treating repeated ISR after CAS.

Revascularization of acute stent thrombosis after carotid artery stenting in a CYP2C19*2 heterozygote patient

Carotid artery stenting (CAS) is an alternative strategy to carotid endarterectomy for the prevention of ischemic stroke. Acute carotid stent thrombosis (ACST) is an extremely rare but devastating complication of CAS. Although cases of successful recanalization have been reported, there is still a lack of experience regarding the choice of ACST treatment methods and the timing of such treatments, especially when patients are confirmed CYP2C19*2 heterozygotes. Here, we report a case of successful revascularization after ACST in a patient with CYP2C19*2 heterozygosity. We also review the literature and discuss appropriate treatment strategies for this devastating and rare event.

Carotid Endarterectomy for Intractable Repetitive Stenosis Following Carotid Artery Stenting

BACKGROUND

Restenosis after carotid artery stenting has raised concerns regarding the long-term durability of carotid stenting. Recurrent restenosis after multiple endovascular interventions may pose a challenge for clinicians.

CASE DESCRIPTION

We encountered 2 cases of intractable restenosis after redo-carotid artery stenting and performed carotid endarterectomy. We removed the embedded stent and plaque simultaneously, used the internal shunting system, and performed patch angioplasty with no further recurrence.

CONCLUSION

Carotid endarterectomy could be considered as a first-line treatment for recurrent stenosis that proves refractory to multiple endovascular interventions.

The management of carotid restenosis: a comprehensive review

Carotid artery stenosis (CS) is a major medical problem affecting approximately 10% of the general population 80 years or older and causes stroke in approximately 10% of all ischemic events. In patients with symptomatic, moderate-to-severe CS, carotid endarterectomy (CEA) and carotid angioplasty and stenting (CAS), has been used to lower the risk of stroke. In primary CS, CEA was found to be superior to best medical therapy (BMT) according to 3 large randomized controlled trials (RCT). Following CEA and CAS, restenosis remains an unsolved problem involving a large number of patients as the current treatment recommendations are not as clear as those for primary stenosis. Several studies have evaluated the risk of restenosis, reporting an incidence ranging from 5% to 22% after CEA and an in-stent restenosis (ISR) rate ranging from 2.7% to 33%. Treatment and optimal management of this disease process, however, is a matter of ongoing debate, and, given the dearth of level 1evidence for the management of these conditions, the relevant guidelines lack clarity. Moreover, the incidence rates of stroke and complications in patients with carotid stenosis are derived from studies that did not use contemporary techniques and materials. Rapidly changing guidelines, updated techniques, and materials, and modern medical treatments make actual incidence rates barely comparable to previous ones. For these reasons, RCTs are critical for determining whether these patients should be treated with more aggressive treatments additional to BMT and identifying those patients indicated for surgical or endovascular treatments. This review summarizes the current evidence and controversies concerning the risks, causes, current treatment options, and prognoses in patients with restenosis after CEA or CAS.

Carotid Free-Floating Thrombus in a Stent 6 Months After Carotid Artery Stenting

BACKGROUND

Carotid free-floating thrombus (CFFT) is defined as a blood clot attached to the arterial wall with surrounding blood flow at its distal component. Although rare, it is a clinically significant cause of embolic stroke. CFFT within a stent has not been previously reported.

CASE DESCRIPTION

We report a 64-year-old man who underwent carotid artery stenting for asymptomatic right carotid artery stenosis. Six months after carotid artery stenting, he was admitted to the emergency department 1 hour after onset of left hemiparesis and dysarthria. His National Institutes of Health Stroke Scale score was 10. His medical history was notable for hypertension, chronic renal insufficiency, and type 2 diabetes mellitus. Carotid ultrasonography showed a dumbbell-shaped CFFT attached to the carotid stent that was moving in synchrony with his heartbeat. CFFT removal was performed via an endovascular approach with manual suction using a Luer Lock syringe. The CFFT was completely removed without residual stenosis. Histologic examination suggested plaque rupture associated with a lipid-rich necrotic core.

CONCLUSIONS

Carotid plaque formation and plaque rupture can occur within a carotid stent and present as a CFFT.

Endovascular Treatment of Acute Carotid Stent Occlusion: Aspiration Thrombectomy and Angioplasty

Introduction

Acute carotid stent occlusion (CSO) is a rare complication of endovascular carotid stent placement that requires emergent intervention. We describe angioplasty or combined angioplasty and aspiration thrombectomy as a new endovascular technique for CSO treatment. The technique is compared to others previously described in the literature.

Methods

We performed a retrospective cohort study of all patients who underwent endovascular treatment (ET) of acute symptomatic CSO from January 2008 to March 2018 at our neurovascular referral center. Patient demographics, endovascular treatment details, and outcome data were determined from the electronic medical record. Primary outcome was successful stent recanalization and cerebral reperfusion (modified thrombolysis in cerebral infarction (mTICI) score IIB-III). Secondary outcomes were National Institutes of Health Stroke Scale (NIHSS) shift from presentation to discharge, mortality, and modified Rankin Scale (mRS) score at 3 months. Additionally, a literature review (years 2008-2019) was performed to characterize other techniques for ET of CSO.

Results

Four patients who underwent ET of acute CSO were identified. ET treatment by angioplasty (n = 1) or combined aspiration thrombectomy and angioplasty (n = 3) resulted in carotid stent recanalization in all patients. Tandem intracranial occlusions were present in three patients (75%), and successful cerebral reperfusion was achieved in all patients. Patient symptoms improved (mean NIHSS shift -5.3 ± 7.2 at discharge). One patient died of a symptomatic reperfusion hemorrhage and another died of cardiac complications by 3-month follow-up. The mRS scores of the surviving patients were 1 and 3. Previously described studies (n = 14) using different and varied techniques had moderate recanalization rates and outcomes.

Conclusion

Combined aspiration thrombectomy and angioplasty for the neurointerventional treatment of acute CSO leads to high rates of stent recanalization and cerebral reperfusion. The recanalization rate here is improved compared to previously reported techniques. Further multicenter studies are required to risk-stratify patients for specific ET interventions.

Acute carotid stent thrombosis

Carotid artery stenting is a method used in the treatment of extracranial carotid artery stenosis that is becoming increasingly more common. Acute carotid thrombosis following CAS is a very rare and devastating complication that can be lethal for the patient unless treated immediately. We report a case of acute carotid stent thrombosis occurring immediately after emergent revascularization, and that was treated with intraarterial tissue plasminogen activator and intravenous tirofiban infusion.

Acute Early Carotid Stent Thrombosis: A Case Series

BACKGROUND

Acute early carotid stent thrombosis (AcuteCST) is a rare complication after carotid artery stenting (CAS). The purpose of this retrospective study was to investigate the incidence, causes, and optimal management of AcuteCST.

METHODS

Medical records of all patients undergoing CAS between 2008 and 2016 were retrospectively reviewed. The time of thrombosis, grade of stenosis, lesion side, preprocedural and postprocedural anticoagulants, causes, symptoms, treatment, recanalization, and outcome were reviewed.

RESULTS

Overall, 674 patients were treated with CAS. Four cases of AcuteCST were identified (0.59%). In the first patient, the stent thrombosis was attributed to dissection caused by filter deployment within a distal internal carotid artery with 360° coiling. Notably, in 3 of the 4 cases of thrombosis a second overlapping stent had been deployed. In total, 41 patients of the cohort under investigation underwent overlapping stent deployment. The use of a second overlapping stent as a bail-out procedure due to dissection or malposition or due to long lesions was correlated with increased rate of thrombosis (3/41 [7.3%] vs. 1/633 [0.002%]). In 2 patients, carotid stents were thrombosed within 2 hr of the procedure. Endovascular thrombus aspiration and subsequent eversion carotid endarterectomy with stent explantation in the first patient and intrathrombus urokinase administration with thromboaspiration and additional stent placement in the second patient were followed. In the other 2 patients having their carotid stents thrombosed 3 and 4 days after the procedure, treatment with low weight molecular heparin and antiplatelet regimens was followed.

CONCLUSIONS

The use of overlapping stents in the carotid artery is a predisposing factor for AcuteCST. Prognostic factors of this potentially devastating complication are the initial clinical presentation expressing the grade of ischemic brain damage, the accurate and timely recognition of the thrombosis, and the prompt restoration of oxygenated blood flow into the viable tissue at risk of infarction.

Anticoagulant therapy for recurrent in-stent thrombosis following carotid artery stenting: A case report

We report a case in which strict anticoagulant therapy management was useful for a recurrent in-stent thrombosis after carotid artery stenting (CAS). An 84-year-old man presented with cognitive decline that progressed rapidly over two months. Head magnetic resonance imaging showed an acute-stage infarct occurring frequently in the right cerebral hemisphere, and he underwent hospitalization and treatment. On neck magnetic resonance angiography (MRA), severe stenosis was found at the origin of the right internal carotid artery. Since he took aspirin, clopidogrel, and a statin after placement of an indwelling coronary stent, we treated him by adding argatroban and edaravone drip therapy to his existing medication. CAS was performed on day 15 of the hospitalization. A small in-stent thrombosis with plaque protrusion was observed on a carotid sonogram performed at the second day after CAS, and re-examination at the seventh day confirmed enlargement of the lesion and an increase in peak systolic velocity; thus, a second CAS procedure was performed on the same day. After the second CAS, oral cilostazol was added for triple antiplatelet therapy (TAPT), but as the in-stent thrombosis increased further, we started a continuous infusion of heparin with the goal of an activated partial thromboplastin time (APTT) of 50 to 65 seconds. After starting heparin, the lesion did not progress; after 14 days of continuous heparin infusion, the patient was switched to TAPT, and regression of the plaque was confirmed. This case demonstrated to us that controlled anticoagulation therapy can be an effective treatment for cases in which a thrombus recurs within a stent after CAS.

Carotid Endarterectomy to Remove Retained Solitaire Stent Retriever inside Carotid Stent after Mechanical Thrombectomy

BACKGROUND

Tandem occlusions of the internal carotid artery (ICA) and middle cerebral artery (MCA) occur in up to a third of patients with acute ischemic strokes undergoing endovascular mechanical thrombectomy. Understanding open neurosurgical management of associated complications with this procedure is important.

CASE REPORT

A 67-year-old man with acute onset of left hemiparesis and a tandem right ICA and MCA occlusion. He underwent carotid stent angioplasty of a stenotic ICA, followed by attempted Solitaire stent retrieval of an MCA clot. On withdrawal, the tines of the Solitaire stent lodged inside the Precise carotid stent. The patient was started on aspirin, Plavix, and heparin infusion, and underwent a carotid endarterectomy (CEA) with safe removal of the stents and primary vessel repair.

CONCLUSION

This is the first case reported to date of a Solitaire stent becoming lodged inside a Precise carotid stent, salvaged by CEA with safe removal of the stents and primary vessel repair. We discuss the timing, indication, alternatives, and technical nuances of a CEA in this setting.

Acute Carotid Stent Thrombosis

Acute carotid stent thrombosis (ACST) is a rare complication that can lead to dramatic and catastrophic consequences. A rapid diagnosis and prompt recanalization of the internal carotid artery are needed to minimize the ischemic insult and the reperfusion injury. We reviewed the current literature on this devastating complication of CAS with the intention of investigating the potential causative factors and to define the appropriate management. According to our study discontinuation of antiplatelet therapy, resistance to antiplatelet agents and inherent or acquired thrombotic disorders are the main causes of thrombosis. Technical intraprocedural parameters such as dissection, atheroma prolapse, kinking of the distal part of internal carotid artery and embolic protection device occlusion can also result in early carotid stent thrombosis. Rapid reperfusion ensures an improved neurological outcome and a better prognosis in the short and long term. Thrombolysis, mechanical thrombectomy or thromboaspiration in combination with drug or thrombolytic therapy, surgical therapy and re-angioplasty are treatment options that have been used with encouraging results. In conclusion, optimal perioperative antiplatelet treatment as well as technical considerations regarding the carotid artery stenting plays a determinant role.

Association of thrombelastographic parameters with post-stenting ischemic events

BACKGROUND AND PURPOSE

Thrombelastography (TEG) is widely used for the measurement of platelet function. However, few studies have investigated the TEG parameters in patients receiving extracranial or intracranial artery stenting for ischemic cerebrovascular disease. This study sought to describe the association of TEG parameters before the procedure with post-procedural ischemic events after extracranial or intracranial artery stenting.

METHODS

Patients in whom stenting was performed for extracranial or intracranial artery stenosis (70-99%) were recruited into the study. Blood samples were obtained for TEG to assess platelet function before stenting. The primary endpoint was ischemic stroke or transient ischemic attack in the territory of the stented artery.

RESULTS

A total of 218 patients were included in the study. During a mean follow-up period of 132 days (range 98-226 days), 18 (8.3%) primary endpoint events were recorded. Compared with patients without ischemic events, the ADP-induced platelet-fibrin clot strength (MA_ADP) was significantly higher (41.57±15.10 vs 33.50±13.86, p=0.020) and the ADP inhibition rate (ADP%) was significantly lower in patients with ischemic events (39.54±23.15 vs 55.29±24.43, p=0.009). Multivariate analysis identified MA_ADP and ADP% as significant independent predictors of subsequent ischemic events with HRs of 1.036 and 0.965, respectively. From receiver operating characteristic curve analysis, MA_ADP >49.95 mm had the best predictive value of ischemic events.

CONCLUSIONS

Our study suggests that TEG parameters MA_ADP and ADP% are associated with subsequent ischemic events in patients with extracranial or intracranial stents.

CLINICAL TRIAL NUMBER

NCT01925872.

Carotid endarterectomy in a young symptomatic patient with B-thalassemia major

β-Thalassemia major promotes atherosclerotic process, although the debating literature concerning the lipidic profile of young patients; it is well accepted that there is early vascular destruction in these homozygous patients either as a direct consequence of the genetic disorder per se or because of the repeated transfusions and the iron overload. Despite the potential of the disease for local brain thrombotic events, accelerated atheromatosis can lead to early thromboembolic events. We present an interesting case of a 36-year-old man with unilateral embolic infarcts (repeated transient ischemic attacks) originated from a near occlusion right carotid stenosis with additional peripheral thrombus. The patient underwent a successful carotid endarterectomy with primary arterial closure with uneventful postoperative course, confirmed by a clear postoperative angiography; he remains asymptomatic 18 months later. To the best of our knowledge, this is the first case of a young symptomatic patient with β-thalassemia major who underwent carotid repair.

Emergent surgical embolectomy for middle cerebral artery occlusion due to carotid plaque rupture followed by elective carotid endarterectomy

Embolic intracranial large artery occlusion with severe neurological deficit is associated with an extremely poor prognosis. The safest and most effective treatment strategy has not yet been determined when such emboli are associated with unstable proximal carotid plaque. The authors performed emergent surgical embolectomy for left middle cerebral artery (MCA) occlusion, and the patient experienced marked neurological recovery without focal deficit and regained premorbid activity. Postoperative investigation revealed “vulnerable plaque” of the left internal carotid artery without apparent evidence of cardiac embolism, such as would be seen with atrial fibrillation. Specimens from subsequent elective carotid endarterectomy (CEA) showed ruptured vulnerable plaque that was histologically consistent as a source of the intracranial embolic specimen. Surgical embolectomy for MCA occlusion due to carotid plaque rupture followed by CEA could be a safer and more effective alternative to endovascular treatment from the standpoint of obviating the risk of secondary embolism that could otherwise occur as a result of the manipulation of devices through an extremely unstable portion of plaque. Further, this strategy is associated with a high probability of complete recanalization with direct removal of hard and large, though fragile, emboli.

Rescue strategy for acute carotid stent thrombosis during carotid stenting with distal filter protection using forced arterial suction thrombectomy with a reperfusion catheter of the Penumbra System: a technical note

BACKGROUND

Among the procedural complications related to carotid artery stenting (CAS), internal carotid artery (ICA) flow arrest is one of the most drastic complications, as it can cause major ischemic stroke. Acute carotid stent thrombosis (ACST) is a rare etiology of ICA flow arrest during carotid artery stenting with distal filter protection, but the most devastating. Moreover, no definitive management strategy has been established so far for treating ACST.

METHODS

We introduce a rescue management strategy for differential diagnosis of ICA flow arrest and for recanalization of ACST with a simple endovascular mechanical thrombectomy technique.

RESULTS

In three cases of ICA flow arrest caused by ACST, selective angiography with a 1.7 F microcatheter provided confirmative diagnosis. Recanalization was then achieved with a Penumbra System (PS) reperfusion catheter using the forced arterial suction thrombectomy (FAST) technique. Successful recanalization with a Thrombolysis In Cerebral Infarction score of 3 was achieved for all three patients. Recanalization was confirmed with follow-up angiography at least 24 h after the procedure. No complications associated with this technique occurred.

CONCLUSIONS

Based on our preliminary experiences, selective microangiography can be helpful for rapid diagnosis of ACST, and the present mechanical thrombectomy technique, using a modification of the PS, can play a role in adjuvant management or as a last resort for the treatment of ACST during CAS.

In-stent thrombosis after carotid artery stenting despite sufficient antiplatelet therapy in a bladder cancer patient

In-stent thrombosis (IST) after carotid artery stenting (CAS) is a rare but potentially devastating complication. We present a case of early IST after CAS despite sufficient antiplatelet therapy in a patient with bladder cancer. A 77-year-old man under preventive triple antiplatelet therapy underwent CAS without any intra- or periprocedural complications. However, the patient developed a large asymptomatic IST 6 days after CAS. Anticoagulant therapy with argatroban was reintroduced to treat IST concomitant with antiplatelet agents. Subsequently, the IST shrank and disappeared without any thrombotic symptoms. Malignancy is regarded as an acquired thrombophilic condition associated with a significant risk of thrombosis. In the field of coronary stents, cancer is associated with a significant increasing risk of IST. The cause of IST in our case was possibly related in hypercoagulable state because of the patient's cancer. Attention for IST should be paid in CAS cases with these risk factors, and repeated examination is recommended.

Immediate surgery for acute internal carotid artery dissection and thrombosis during filter deployment prior to stenting: a case report

Carotid artery stenting (CAS) is a validated option in the treatment of selected extracranial carotid artery stenosis. Carotid artery dissection during CAS is a rare but potentially devastating complication. We report a case of acute dissection and thrombosis of the left internal carotid artery during filter tip wire engaging maneuvers, complicated by intraoperative complete blindness of the left eye. Immediate conversion to carotid endarterectomy was performed under general anesthesia with electroencephalographic monitoring. The patient was discharged home symptomless and remains asymptomatic eight months after the operation, with normal left internal carotid patency and fully recovered eyesight. In conclusion, the management of acute carotid occlusion during CAS requires emergent evaluation and definitive endovascular or open surgical repair to minimize neurologic morbidity. We advocate that all endovascular procedures are carried out in a well-established surgical environment.

Acute carotid stent thrombosis: a case of surgical revascularization and review of treatment options

Carotid artery stenting is considered to be an alternative to carotid endarterectomy for selected patients by many vascular specialists around the world. Acute stent thrombosis following the procedure, although very infrequent, can risk the survival of the patient. In this report, we present a case of acute stent thrombosis 24 hours following the procedure. After a slow deterioration of the clinical state of the patient, he was urgently subjected to thrombectomy with extraction of the stent, with eventual resolution of his symptoms. A review of the current literature is presented together with all the possible treatment options of this serious complication. In conclusion, several neurorescue procedures are available for the vascular surgeon who has to act urgently and, in some cases, aggressively, when stent thrombosis is diagnosed.

Classification for carotid artery stenting complications: manifestation, management, and prevention

Carotid artery stenting is a rapidly evolving method for treating carotid artery disease. Various intraprocedural and postprocedural complications have been reported in the literature. However, the absence of a unified classification scheme for these complications makes it difficult, if not impossible, to study their precise incidence, predictors, and management. The aim of this article is to propose the first joint classification of periprocedural complications, to analyze their incidence and etiology, and suggest possible ways to manage and prevent them. This classification is intended to be used as a common platform for prompt recognition, evaluation, treatment, and universal study of the complications during carotid stenting procedures. For this purpose, the opinions of the major experts on carotid interventions worldwide were merged with all the available information reported in the English-language literature to present as accurately as possible the management and prevention of carotid stenting complications according to this proposed classification.

Carotid stent removal of symptomatic plaque protrusion after carotid angioplasty stenting

We treated two patients with asymptomatic high grade internal carotid artery stenosis, by carotid artery stenting (CAS) with embolus protection filters 75% and 70%, respectively (North American Symptomatic Carotid Endarterectomy criteria). The immediate cranial and carotid angiogram showed a good result with regular patency of carotid and cerebral vessels. In both cases, the CAS procedure was complicated with symptomatic embolism, in one case 6 h after CAS and the other one occurring after seven days. The duplex scan (DS) control revealed the presence of plaque protrusion intra-stent in both cases. An early treatment with stent removal and carotid surgery was performed <24 h after the presenting symptoms (in one case a standard endarterectomy in the other and a carotid bypass was performed). Both patients were discharged without neurological deficit. At neurological follow-up at 30 days the patients were in good general condition without neurological symptoms or deficit and the DS follow-up at 30 days and six to 12 months show the patency of carotid vessels. These two cases demonstrate that plaque protrusion is a possible complication of CAS, where symptoms which may occur either immediately or later and can be managed successfully with urgent surgical intervention of carotid stent removal.

Carotid stenting and bivalirudin with and without vascular closure: 3-year analysis of procedural outcomes

OBJECTIVES

The purpose of this study was to examine the outcome of carotid stenting using bivalirudin and the influence of vascular closure devices (VCD) on the incidence and severity of peri-procedural hypotension.

BACKGROUND

Bivalirudin, a short-acting direct thrombin inhibitor, has been shown to be an effective anticoagulant in coronary interventions, with less risk of bleeding compared with heparin. Routine use of VCD has become the standard of care, facilitating patient ambulation after percutaneous carotid and coronary interventions. The combined use of these two therapies (bivalirudin and VCD) may improve outcomes in carotid interventions where prolonged patient immobilization may exacerbate hypotension following stenting.

METHODS

A total of 514 patients underwent 536 carotid stenting procedures in the 3-year period from September 2004 to September 2007. All patients received adjunctive bivalirudin, with and without VCD. This cohort was analyzed for peri-procedural and 30-day clinical outcomes and length of hospitalization.

RESULTS

Thirty-day stroke and death rate was 1.7%. A total of 83 patients (15.4%) experienced intra- or post-procedural hypotension (systolic BP < 80 mm Hg). There were four (0.7%) major bleeding complications requiring transfusion, and length of stay was delayed more than 24 hr in five patients (0.93%), all of whom were in the manual compression group.

CONCLUSIONS

This was a negative study, with no significant difference on prolonged hypotensive events in patients with vascular closure device and bivalirudin, compared with those with manual compression and bivalirudin. Vascular closure devices were safe and effective with a low incidence of complications. In carotid artery stenting, bivalirudin is safe with low incidence of major bleeding and acceptable 30-day adverse event rates (stroke and death).

Recurrent subacute in-stent restenosis after carotid artery stenting due to plaque protrusion

A 70-year-old male presented with transient ischemic attacks manifesting as right hemiparesis and motor aphasia due to severe left cervical internal carotid artery stenosis. Carotid artery stenting (CAS) using a flow-reversal system was performed without complications. However, the patient exhibited transient right hemiparesis and motor aphasia 10 days after CAS. Emergent angiography demonstrated in-stent restenosis. In-stent percutaneous transluminal angioplasty and CAS were performed successfully using a distal protection system. However, duplex ultrasound scanning revealed progressive in-stent restenosis, 3 and 6 days after the re-treatment. Emergent angiography again demonstrated in-stent restenosis. Urgent stent removal and carotid endarterectomy were performed. Plaque had prolapsed through the stent. Histological examination revealed that the specimen was mainly plaque consisting of cholesterol crystals and macrophages. The patient was able to return to independent life without neurological deficit. Repeated endovascular surgery with appropriate antiplatelet and anticoagulation therapy should be attempted initially to treat in-stent restenosis. Endarterectomy with stent removal should be considered as a rescue option, especially if plaque protrusion is identified.

Frequency and consequences of early in-stent lesions after carotid artery stent placement

PURPOSE

To examine the prevalence of in-stent lesions 1 month after carotid artery stent placement with multidetector computed tomography (CT) angiography and to evaluate their possible causes and their consequences during 1-year follow-up.

MATERIALS AND METHODS

Sixty-nine patients with symptomatic carotid artery stenosis underwent multidetector CT angiography of the carotid arteries 1 month after carotid artery stent placement. Patients were followed-up until 1 year after stent placement, when duplex ultrasonography (US) was performed. In-stent lesions were defined as hypo- or hyperattenuating lesions at the stent wall found with multidetector CT. Significant restenosis (70%) at 1 year was defined as a peak systolic velocity of more than 300 cm/sec at duplex US. The Fisher exact test was used to assess the relationship between early in-stent lesions and ischemic events and restenosis.

RESULTS

At 1 month, 14 of the 69 patients (20%) were found to have in-stent lesions. In one patient, the stent was occluded. The other 13 in-stent lesions did not result in significant lumen reduction. In the year following stent placement, no difference in ischemic events was found between patients with (14%) and those without (13%) early in-stent lesions (P = .99). There was no difference in the occurrence of restenosis at 1 year (7% vs 4%, P = .59).

CONCLUSIONS

At 1 month after carotid artery stent placement, in-stent lesions are found in about one-fifth of patients. These lesions do not appear to be related to recurrent ischemic events or to restenosis at 1 year.

Refractory In-stent Restenosis Following Carotid Artery Stenting: A Case Report and Review of Operative Management

In-stent restenosis following carotid artery stenting is a challenging problem that vascular surgeons will likely encounter with increasing frequency. The following describes a patient who developed progressive in-stent restenosis 3 years after carotid artery stenting, which was treated with operative therapy after failed balloon angioplasty. A review of the literature describing surgical approaches to the treatment of in-stent restenosis was also performed.

Small in-stent Low Density on CT Angiography after Carotid Artery Stenting

SUMMARY

Carotid stenting (CAS) for carotid stenosis has developed rapidly over the last decade. Instent low density area supposed plaque protrusion or thrombus is sometimes observed on CT angiography after CAS. We evaluate the frequency and time course of the small in-stent low density after carotid artery stenting and discuss its nature and clinical significance. Between May 2005 to November 2007, 23 CASs were performed for 20 patients with carotid artery stenosis. All patients had no instent defect on digital subtraction angiography (DSA) immediately after the procedure. Followup CT angiography was performed at seven 7-10 days, 1-2 months, 6 months, and then every 6 months following CAS. We retrospectively reviewed the follow-up CT angiographic findings and clinical ischemic events. Small in-stent low density areas on CT angiography were observed in 6 lesions (26%). Four cases were added warfarin to antiplatlets and the other two cases had antiplatlets only. The in-stent low density areas were disappeared within four months after CAS and no ischemic event was observed in five patients. In the other patient, a small in-stent low density area had decreased at one month after CAS, but another small in-stent low density area appeared at five months. Subacute small in-stent low density areas were frequently observed on CT angiography following CAS, however, the low density area will disappear without clinical events by medication in most case.

Rescue use of tirofiban for acute carotid in-stent thrombosis

Carotid artery stenting is widely performed for extracranial carotid artery stenosis. In-stent thrombosis is a rare but potentially devastating complication. We present a case of acute in-stent thrombosis immediately following stent insertion and post-balloon dilatation in a 64-year-old male. Thrombosis was successfully treated by intravenous tirofiban, a glycoprotein IIb/IIIa receptor inhibitor.

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.

Carotid Artery Stenting in a Single Center: Are Six Years of Experience Enough to Achieve the Standard of Care?

OBJECTIVES

This study aims to determine safety, short and mid-term outcomes of Carotid Artery Stenting (CAS) and Endarterectomy (CEA) during the last 6 years in a single vascular surgery center.

METHODS

We retrospectively reviewed 2624 consecutive carotid revascularizations performed between December 2000 and December 2006 in 2176 patients with severe carotid artery stenosis (symptomatic > or = 70%, asymptomatic > or = 80%), of which 1589 were CEA and 1035 CAS. Patients were followed up at 1, 3, 6 and 12 months after the procedure and then yearly.

RESULTS

The percutaneous procedure was successful in 99.2% of the cases. No intra-procedural death occurred. The overall death and stroke rates at 30 days, 1 year and 3 years were 1.54%, 2.86%, 7.43% in the CAS group and 2.07%, 3.55%, 6.95% in the CEA group, respectively (p value not significant in any case).

CONCLUSIONS

At our vascular surgery centre the results of CEA and CAS are similar. CAS has become our standard of care in preventing strokes and is an effective alternative to CEA for low-risk patients as well.

Carotid Stent Failure: Results of Surgical Rescue

AIM

Little data is available on surgical "rescue" of failed carotid stents (CAS). We have analyzed a series of CAS failures treated by conventional open surgery.

REPORT

Five patients underwent surgery after CAS failure, either electively (4) or as an emergency (1). Elective surgical "rescue" was for stent restenosis (2 cases) or stent misplacement (2 cases). Emergency surgery was performed for entrapment of the protection system in the stent. Surgical rescue was accomplished by perimedial endarterectomy and "en bloc" plaque and stent extraction in 3 cases, and by vein bypass in 2 cases, with no neurological complications.

CONCLUSION

Surgical rescue of failed CAS is effective.