Abstract

Objective: To determine the safety and efficacy of flow reversal following proximal flow arrest as an embolic protection strategy for carotid angioplasty and stenting (CAS) with short-term follow-up. Method: We performed a retrospective review of our CAS database for patients who underwent stent-supported carotid revascularization in the setting of acute/subacute stroke or TIA. We reviewed clinical and radiographic data during a 36-month period. Primary outcome was clinical evidence of ipsilateral stroke in the first 30 days. Secondary outcomes include clinical outcomes and sonographic and/or angiographic follow-up over 6 months, 6-month functional scale, and all-cause mortality. Results: Fifty-five patients underwent CAS using flow reversal: 26 females and 29 males with a mean age of 69.7 years. Median time to treatment from index event was 3 days. 11% underwent stenting as part of hyperacute stroke therapy. Average luminal stenosis was 86%. The 9-Fr Mo.Ma device was used in combination with Penumbra aspiration in all cases. There were no ipsilateral strokes. Incidence of any ischemic event was 3.64%, but only 1 (1.82%) patient had a postoperative stroke. Clinical follow-up was available for 94.5%, while lesion follow-up was available for 73% of patients. Three patients had evidence of restenosis, but none were symptomatic. Luminal restenosis was ≤30% in all three. Median pre- and post-NIHSS were 1 and 1, respectively. Conclusion: Flow reversal using the Mo.Ma device is a safe and effective strategy in preventing distal embolization during carotid artery revascularization.

© 2019 S. Karger AG, Basel

Introduction

Stroke is the fifth most common cause of mortality as well as a significant cause of disability in the United States [1]. Nearly one-fourth of ischemic stroke cases are recurrent strokes [2]. 20–30% of these strokes are secondary to extracranial carotid artery stenosis [3, 4]. Symptomatic lesions which are greater than 70% on duplex ultrasonography or >50% on catheter-based angiography have a recurrence rate of about 26% for ischemic events if treated with medical management alone [5, 6]. This latter group is strongly recommended to undergo carotid revascularization provided the incidence of perioperative ischemic events or mortality is <6% [7].

Carotid artery stenting is a viable alternative to carotid endarterectomy (CEA) in many cases [8, 9]. Embolic protection devices (EPDs) have been found to reduce the incidence of ipsilateral ischemic complications [10-14]. Several studies also suggest that proximal balloon occlusion is superior to distal protection device in preventing embolic complications [15, 16]. The ARMOUR study proved that the Mo.Ma device is safe, efficacious, and comparable to distal protection devices in preventing such complications [17]. Further lack of data as well as relative inexperience with the device may have contributed to the lower application of this strategy. Proximal balloon occlusion with flow reversal via aspiration using the Mo.Ma device, in particular, has never been studied.

Objective

To determine the safety and efficacy of flow reversal following proximal flow arrest as an embolic protection strategy for carotid angioplasty and stenting (CAS) with short-term follow-up.

Methods

Following an institutional review board approval, we performed a retrospective review of our prospectively maintained carotid stenting database from 2013 through 2016. The cases included for this review were those who had a TIA or stroke 6 months prior to the procedure, acutely occlusive cervical ICA lesions with or without intracranial occlusions and asymptomatic cases with greater than 70% stenosis on carotid Doppler.

We excluded cases with a large infarct in the upstream ipsilateral distribution, those with a poor functional baseline (modified Rankin scale [mRS] >4), chronic total occlusion of the internal carotid artery, tortuous anatomy precluding endovascular intervention and nonatherosclerotic etiologies for luminal compromise like dissection, carotid web, or flow-limiting thrombus.

We used several study definitions. An index event was either a TIA or stroke whose workup led to the identification of the carotid stenosis and was the closest, temporally, to the procedure. All lesions were atherosclerotic in nature. Hyperacute stroke therapy was defined as cases where carotid revascularization was performed for an acutely occlusive cervical ICA presenting as an emergent ischemic stroke. These may or may not have been associated with an intracranial occlusion. Ischemic events were either TIA that did not have any infarction on MRI or strokes with positive findings on imaging (CT or MRI). A stroke neurologist who was the primary admitting and discharging physician for all the CAS patients in this review independently assessed them. Their assessments were recorded independently of the neurointerventionalist as part of the prospective carotid database. Postoperative strokes were infarcts within 30 days of the procedure of which early perioperative were those which occurred within 24 h of the procedure.

Intake variables included demographic and clinical variables. Demographic variables were age and sex. Clinical variables included vascular risk factors (diabetes, hypertension, hyperlipidemia, and smoking), type of clinical presentation, symptomatic status of the lesion, time to treatment from index event, and preprocedural neurological (NIHSS) and functional (mRS) status. Procedural variables included lesion-related and technical variables. The former included degree of stenosis, location of lesion as well as presence of tandem lesions. The latter primarily included type (pre- and post-) and sizes of angioplasty balloons and stent used. Outcome variables included the following: postoperative NIHSS, perioperative ischemic events, ipsilateral or otherwise, discharge mRS, 3–6 monthly clinical outcomes including ischemic events and mRS as well as follow-up restenosis on carotid Doppler at latest follow-up.

Procedural Details Procedure Preparation

Preprocedurally, patients were given 325 mg of aspirin daily and clopidogrel either as a single loading dose or as divided doses totaling up to 300–600 mg. The bolus was given for urgent cases of revascularization. Patient testing for clopidogrel responsiveness was not available for the first 2 years, but thereafter the dose was increased until a therapeutic level was achieved. For hyperacute stroke therapy, patients either received intraoperative clopidogrel via a nasogastric tube or IV eptifibatide (Merck & Co., Kenilworth, NJ, USA) until oral antiplatelet agents could be given. All procedures were done under conscious sedation.

Procedural Technique

The common carotid artery was catheterized proximal to the stenosis with a diagnostic catheter. Thereafter, the diagnostic catheter was exchanged for a 9-Fr Mo.Ma (Medtronic, Fridley, MN, USA) guide catheter. The external carotid artery (ECA) balloon of the Mo.Ma device was inflated next. The lesion was then crossed with the help of a 190-cm balance medium weight microwire or a 200-cm Synchro2 Standard (Stryker Neurovascular, Fremont, CA, USA) microwire. Next, the common carotid balloon was inflated. The lesion was crossed with the microwire before the common carotid balloon was deployed to reduce duration of flow arrest. If the stenosis was extremely narrow and not amenable to primary stenting, preangioplasty with appropriately sized Sterling balloon catheter (Boston Scientific, Boston, MA, USA) was performed. In cases where the stenosis could be crossed directly, an appropriately sized carotid stent was deployed across the stenosis. PRECISE (Cordis Corporation, Fremont, CA, USA) carotid stents were used for all the cases. In most cases, postangioplasty with an appropriately sized balloon catheter was performed to keep residual stenosis at a minimum. Sterling balloons were used for all the cases for preangioplasty and/or postangioplasty.

Proximal flow arrest was maintained throughout these steps. Flow reversal using aspiration was performed for 30 s following preangioplasty, stenting, and postangioplasty, respectively. Penumbra (Penumbra Inc., Alameda, CA, USA) aspiration tubing as well as aspiration device were used for flow reversal in all cases. First, the ECA balloon was taken down followed by the CCA balloon. This step was followed in order to prevent embolization of any column thrombi formed between ECA and CCA balloons during flow arrest. Once again, flow reversal through aspiration at the base of the Mo.Ma was maintained throughout these deflations. The total time for flow arrest was typically kept within 6 min and never greater than 8 min. The latter was only done if a robust anterior communicating or posterior communicating artery that measured greater than 1 mm was visualized on the preinterventional diagnostic cerebral angiogram. Follow-up angiographic imaging of the extracranial and intracranial circulation was obtained. If there were no complications, the microwire was removed and the arteriotomy closed using an 8-Fr Angioseal. Activated clotting time was maintained between 200 and 300 s during the procedure using intravenous heparin.

A postoperative NIHSS was performed after the completion of the procedure. Patients were transferred to the neuroscience progressive care unit for further monitoring under the primary care of a stroke neurologist.

A case illustration of the technique and peri-procedural result is described in Figure 1.

Fig. 1.

Case illustration. An octogenarian patient presented with left arm weakness and neglect. a MRI revealed multiple embolic infarcts of frontoparietal region. b CTA found 90% stenosis of mid-cervical ICA, which was confirmed on angiography. The patient was at high surgical risk secondary to history of CHF and CAD s/p multiple stents. Mo.Ma was used for CAS 3 days later (c) with successful stent-based revascularization (d). There was no postoperative morbidity. Length of hospital stay was 2 days. 30-day mRS was 2.

Result Analysis and Statistics

Our primary outcome measure was evidence of an ipsilateral stroke in the first 30 days. Any stroke was a clinical event with neurological worsening with confirmed infarction on MRI. Secondary outcomes included evidence of any ischemic event (stroke or TIA), ipsilateral or otherwise, 30-day mRS, and all-cause mortality. Any clinical change in the neurological status prompted further imaging with MRI. Those cases with infarction on MRI were labeled as a stroke while others were considered a TIA.

Clinical follow-up was conducted in the stroke neurology clinic by an independent stroke neurologist or stroke nurse practitioner. The mRS for follow-up was recorded during these visits. The carotid Doppler follow-up was done in the vascular lab which was independent of the neurointerventional clinic and the reports recorded during the retrospective review. In some cases, CTA or angiogram was done. The research coordinator for the carotid database collected the degrees of stenosis recorded in these cases retrospectively.

Descriptive statistics including mean, median, standard deviation, as well as percentages were used to describe the variables and outcomes. We assumed that our population followed a nonparametric distribution for the purpose of this analysis.

Results Demographic and Clinical Variables

Fifty-five patients qualified as per the selection criteria. 47.3% (26) were females and 52.7% (29) were males. Average age was 69 years and 6 months (range 53–96 years). Risk factor distribution was as follows: 92.7% (n = 51) HTN, 47.3% (n = 26) diabetes, 72.7% (n = 40) hyperlipidemia, 45.5% (n = 25) remote or current smoking history, 40.0% (n = 22) coronary artery disease, 38.2% (n = 21) had history of CVA prior to the index event and 12.7% (n = 7) had CHF. Only 7.3% (n = 4) had concomitant atrial fibrillation. 10.9% (n = 6) of the cases were done as hyperacute stroke therapy of which 2 underwent intracranial mechanical thrombectomy. 80% (n = 44) of the patients were treated for symptomatic lesions of which 54.5% (n = 30) were secondary to ischemic stroke. All patients who were symptomatic had an MRI to deem if the ischemic events were TIA or infarcts. Median time to treatment was 3 days. Median preoperative mRS and NIHSS were 1 and 1, respectively. Mean preoperative NIHSS was 5. The patients who were thought to be at high risk for CEA included 23 patients with cardiac history and 6 who were considered to have hyperacute strokes (Table 1).

Table 1.

Demographic and clinical variables

Procedural and Periprocedural Data

Average and median angiographic stenosis was 85.6 and 87% (range 50–99%). 50.9% (n = 28) of the lesions were on the right. 67.3% (n = 37) were associated with other arterial lesions distally or in the contralateral ICA. 11% (n = 6) cases had contralateral ICA occlusion. Preangioplasty was performed in 41.1% (n = 21) patients, while 76.4% (n = 42) had postangioplasty performed. IV eptifibatide at 50% cardiac dose (bolus of 90 μg/kg and IV infusion of 0.5–1 μg/kg/min) dose was used in 21.8% (n = 12) of the cases (Table 2).

Table 2.

Procedural and periprocedural variables

Postprocedural Short-Term and Mid-Term Follow-Up Outcomes

There were no perioperative ipsilateral strokes. Thus, our primary outcome was 0%. One patient had an ipsilateral TIA (2%) a week later, without any evidence of infarction on MRI. One patient (2%) had an early periprocedural stroke (<24 h of stenting) in the contralateral hemisphere. The contralateral hemisphere was an isolated hemisphere and had a proximal ICA occlusion. The patient had hypotension from carotid baroreceptor reflex after carotid revascularization. Therefore, we felt that the mechanism may be related to hypotension-induced hypoperfusion. One patient had hemorrhagic conversion 5 days after the procedure. This patient had received IV tPA on the first day of his presentation, and during his stroke workup was found to have carotid stenosis. 24 h after tPA, he had no hemorrhagic conversion from thrombolysis, so he was loaded with aspirin and clopidogrel. The next day, he underwent CAS. Two days after the procedure, he presented with hemorrhagic conversion that was found on an MRI prompted by new-onset headaches and seizures. However, his NIHSS did not change, and he had no focality to his neurological complaints. He was discharged home with no residual symptoms. One patient had immediate postoperative NIHSS increase of 1 point due to postanesthesia disorientation but returned to baseline later that day. He underwent an MRI, which was negative for infarction. Two patients had groin complications (4%), both femoral pseudo-aneurysms. Median postprocedure length of stay was 3 days, and this included acute/hyperacute stroke patients recovering from their index event. Median discharge-mRS and post-NIHSS were 0 and 1, respectively.

Clinical follow-up at 12 months was available for 52 out of the 55 patients (94.5%). Median time to clinical follow-up was 6 months. Three patients out of the 55 had insignificant recovery from their initial ischemic events and therefore were dead (1 out of 3) or in palliative care (2 out of 3) during the follow up. None of the patients had delayed ischemic events. Median discharge NIHSS was 1, and mRS was 0. 73% of the patients had vascular follow-up of their carotid stents. Median vascular follow-up was 6.2 months. Thirty-six of the 40 patients had a carotid Doppler as follow-up, while 4 patients had an angiographic follow-up (CTA or angiogram). Only 3 patients had evidence of restenosis; 2 were 30%, while 1 was 20% (Table 3).

Table 3. Discussion

Several trials have compared CAS to CEA in the last 15 years [7, 18-23]. The common primary and/or secondary end point for most of these studies included the following: perioperative stroke, postoperative ipsilateral stroke, and mortality. The seminal study CAVATAS revealed that CAS was noninferior to CEA [21]. This was shown in several other studies including SAPPHIRE and SPACE [18, 20, 22-23]. Most of these studies were however limited by unequal enrollment, nonunanimous use of EPDs as well as poor and selective randomization [2, 7]. Another trial, ICSS, was designed to address these issues and revealed positive outcome in favor of CEA but criticism of operator experience and lack of updated technology made the results less generalizable [18]. The most widely respected and the only level 1A evidence in this regard has come from the comprehensive, multicenter CREST trial [19]. Rates of 30-day stroke, myocardial infarction (MI) or death were comparable between CEA and CAS (5.2 vs. 4.5% respectively). CAS, however, had a higher rate of perioperative stroke (4.1 vs. 2.3%) but following this period, the event rates were similar: 2.0% for CAS vs. 2.4% for CEA [2, 19].

However, since the use of EPDs has become universal practice, patients who undergo CAS placement with embolic protection have seen a reduction in postoperative ipsilateral stroke from 4.1 to 1.7% and a reduction in the rate of all nonfatal strokes and all-cause deaths from 4.9 to 2.1% [24]. Various types of EPDs have since been developed, the most common types being distal filter placement, distal occlusion, and proximal occlusion. The SAPPHIRE study showed that use of distal filter devices such as the Cordis AngioGuard had a 4.4% risk for major adverse effects (death, stroke, or MI) after 30 days, making distal protection a viable alternative for patients that are at high surgical risk for CEA [25]. The Medtronic Mo.Ma device is a proximal occlusion device that is used to occlude both external carotid and common carotid to create ante-grade flow arrest and prevent embolization of debris created from angioplasty and stenting. The ARMOUR study involving the Mo.Ma device showed that the 30-day risk for major adverse events was 2.7%, with a 30-day major stroke rate of 0.9% [17]. This has been further validated by postoperative DW-MRI, with the Mo.Ma device having 40% fewer lesions when compared to DPD (p < 0.001) [26, 27]. The major limitation to the use of the Mo.Ma device is occlusion intolerance. Two studies have shown that during a 4- to 6-min period of ICA occlusion, transient intolerance to flow blockage is seen in 5.7–7.6% of patients [28, 29]. The PRIAMUS study also showed that composite postoperative all-stroke and death rate for CAS with use of the Mo.Ma device is approximately 4.56%, with none of them reported in the periprocedural period [28].

Our results indicate that the incidence of the primary outcome, i.e. ipsilateral stroke was 0%. Our periprocedural all-stroke rate in symptomatic patients was 1.8%, which is lower than any of the previous CAS studies (including the stenting arm of the CREST-I trial where the rate of stroke was 6%) [19]. Our periprocedural stroke rate is in fact comparable to the CEA arm of the CREST trial where the rate of stroke/death in the periprocedural period for symptomatic patients was reported as 2.3% [30]. For asymptomatic patients, the rate of stroke or death was 0% in our study compared to 2.5 and 1.4% for the CAS and CEA arms of the CREST trial, respectively [19]. Our periprocedural incidence of MI was 1.8%, which is also comparable to the incidence of MI in CEA studies [5, 19, 30]. We also have 1-year follow-up for 25 patients where none of the patient had a stroke. As compared to the CAS arm of the CREST trial, we did not have any ipsilateral major or minor strokes. The one stroke that was seen in our symptomatic population could have been related to baroreceptor-induced hypotension culminating in hypoperfusion of an isolated hemisphere with a proximal ICA occlusion. Hypotension is a common side effect of angioplasty secondary to baroreceptor reflex but is often self-resolving as was the case in 88% of our patients. 6% of the patients required midodrine postoperatively, but the hypotension resolved over a week. This however did not contribute to prolongation of the length of stay. One patient had evidence of hemorrhagic conversion with no significant change in the NIH stroke scale and with near-complete recovery in the postoperative 30-day period. We believe this was secondary to early poststroke (2 days from presentation) revascularization in a patient who received IV tPA on the first day and aspirin and Plavix load on the second day of presentation. We successfully used Integrilin in about 22% of cases with no reperfusion hemorrhage after procedure.

Of note is the fact that the average age of our group was 69.7 years, which is comparable to the study age group in the CREST trial [19]. However, there were fewer females, and the age range of patients treated for carotid stenosis was wider in our study. 25% of our patients were treated for asymptomatic lesions, 79% of those lesions had >80% stenosis. The incidence of nonneurological complications like groin hematoma and femoral pseudo-aneurysm/AV fistula was 4% in our study. The risk of perioperative local, nonneurological complications was 9.3%, and that of cranial nerve injury was 8.6% in CEA-related studies [30]. There was no mortality in our age group. The pre- and post-NIH stroke scale scores were similar in the prestenting and the poststenting group. Although we were only able to do follow-up imaging for 73% of the treated lesions, only 3 patients (5%) had restenosis, which was less than 30% in all cases. All the restenosis lesions were asymptomatic but required the extension of dual antiplatelet therapy. The average length of postoperative stay was 3 days, which included hyperacute stroke therapy cases. Our average outpatient procedure length of stay was 1.5 days. This is a significant fiscal benefit in the current age of economic hospitalizations.

The study has several limitations. It is a retrospective case series with significant case experience limited to a single operator. Only one stent system was used in all cases. The average duration of proximal occlusion was 6 min, which is similar to the ARMOUR study, and the safety margin of longer proximal occlusion is currently not known. In cases where there is complete ECA occlusion or stenosis, the deployment of the device is not feasible. Similarly, in cases of extremely tortuous anatomy, CEA is still our preferred modality of revascularization. Our study only has short-term results with high attrition, which makes long-term feasibility difficult to assess. Lastly, our study has a small sample size, which makes the results difficult to generalize, and further studies including double-blind randomized controlled trials may be needed for the absolute treatment effect to be assessed.

Conclusion

Proximal flow arrest with flow reversal is a safe and effective alternative to a distal protection device. Our data have comparable rates of ischemic events to CEA and fewer reported nonneurological complications than CEA or distal protection device-based CAS.

Statement of Ethics

Institutional review board approval was obtained prior to starting work on the carotid database as well as analysis and publication of this document. Patient consent was taken prior to the procedure for representation of the data. Since the entire study was retrospective data collection, there were no extra interventions or risks involved to the patient from the conduct of the study.

Disclosure Statement

This research has no competing interests for any of the authors. This includes partial ownership, stocks, stock options, or any other investor roles as well as any consultancy roles.

Funding Sources

This research including all of the abovementioned authors has not received any grant from any funding agency in the public, commercial, or not-for-profit sectors.

Author Contributions

Dr. Ambooj Tiwari was responsible for designing the research. He was also involved in acquisition, analysis, and interpretation of data. He drafted the research paper including its final approval. He is accountable for all aspects of this work and ensures that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Dr. Ryan Bo was responsible for collecting, analyzing and interpreting the data. He was involved in drafting the research paper as well as its final approval. He is accountable for all aspects of this work and ensures that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Dr. Karthikeyan M. Arcot was responsible for making significant contributions to the concept and design of this research. He was involved in drafting the research paper as well as its final approval.

Dr. Keithan Sivakumar was responsible for analyzing and interpreting the data. He was involved in drafting the research paper as well as its final approval.

Dr. David T. Parrella was responsible for analyzing and interpreting the data. He was involved in drafting the research paper as well as its final approval.

Dr. Jeffrey Farkas was responsible for making significant contributions to the concept and design of this research. He was also involved in acquisition, analysis, and interpretation of data. He drafted the research paper including its final approval. He is accountable for all aspects of this work and ensures that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

References http://www.cdc.gov/nchs/data/dvs/LCWK9_2013.pdf Benjamin EJ, Blaha MJ, Chiuve SE, Cushman M, Das SR, Deo R, et al.; American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Heart disease and stroke statistics—2017 update: a report from the American Heart Association. Circulation. 2017 Mar;135(10):e146–603. Petty GW, Brown RD Jr, Whisnant JP, Sicks JD, O’Fallon WM, Wiebers DO. Ischemic stroke subtypes: a population-based study of incidence and risk factors. Stroke. 1999 Dec;30(12):2513–6. Timsit SG, Sacco RL, Mohr JP, Foulkes MA, Tatemichi TK, Wolf PA, et al. Early clinical differentiation of cerebral infarction from severe atherosclerotic stenosis and cardioembolism. Stroke. 1992 Apr;23(4):486–91. Barnett HJ, Taylor DW, Eliasziw M, Fox AJ, Ferguson GG, Haynes RB, et al. Benefit of carotid endarterectomy in patients with symptomatic moderate or severe stenosis. North American Symptomatic Carotid Endarterectomy Trial Collaborators. N Engl J Med. 1998 Nov;339(20):1415–25. Randomised trial of endarterectomy for recently symptomatic carotid stenosis: final results of the MRC European Carotid Surgery Trial (ECST). Lancet. 1998 May;351(9113):1379–87. Brott TG, Halperin JL, Abbara S, Bacharach JM, Barr JD, Bush RL, et al. 2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideline on the management of patients with extracranial carotid and vertebral artery disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American Stroke Association, American Association of Neuroscience Nurses, American Association of Neurological Surgeons, American College of Radiology, American Society of Neuroradiology, Congress of Neurological Surgeons, Society of Atherosclerosis Imaging and Prevention, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, Society for Vascular Medicine, and Society for Vascular Surgery. J Am Coll Cardiol. 2011 Feb;57(8):e16–94. Roubin GS, Iyer S, Halkin A, Vitek J, Brennan C. Realizing the potential of carotid artery stenting: proposed paradigms for patient selection and procedural technique. Circulation. 2006 Apr;113(16):2021–30. Lam RC, Lin SC, DeRubertis B, Hynecek R, Kent KC, Faries PL. The impact of increasing age on anatomic factors affecting carotid angioplasty and stenting. J Vasc Surg. 2007 May;45(5):875–80. Mas JL, Chatellier G, Beyssen B, Branchereau A, Moulin T, Becquemin JP, et al.; EVA-3S Investigators. Endarterectomy versus stenting in patients with symptomatic severe carotid stenosis. N Engl J Med. 2006 Oct;355(16):1660–71. Ringleb PA, Allenberg J, Brückmann H, Eckstein HH, Fraedrich G, Hartmann M, et al.; SPACE Collaborative Group. 30 day results from the SPACE trial of stent-protected angioplasty versus carotid endarterectomy in symptomatic patients: a randomised non-inferiority trial. Lancet. 2006 Oct;368(9543):1239–47. Kim SJ, Roh HG, Jeon P, Kim KH, Lee KH, Byun HS, et al. Cerebral ischemia detected with diffusion-weighted MR imaging after protected carotid artery stenting: comparison of distal balloon and filter device. Korean J Radiol. 2007 Jul-Aug;8(4):276–85. International Carotid Stenting Study Investigators; Ederle J, Dobson J, Featherstone RL, Bonati LH, van der Worp HB, de Borst GJ, et al. Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): an interim analysis of a randomised controlled trial. Lancet 2010;375(9719):985-97. Garami ZF, Bismuth J, Charlton-Ouw KM, Davies MG, Peden EK, Lumsden AB, et al. Feasibility of simultaneous pre- and postfilter transcranial Doppler monitoring during carotid artery stenting. J Vasc Surg. 2009 Feb;49(2):340-4, 345.e1-2; discussion 345. Stabile E, Salemme L, Sorropago G, Tesorio T, Nammas W, Miranda M, et al. Proximal endovascular occlusion for carotid artery stenting: results from a prospective registry of 1,300 patients. J Am Coll Cardiol. 2010 Apr;55(16):1661–7. White CJ. Proximal embolic protection: a “game changer” for carotid stents. J Am Coll Cardiol. 2010 Apr;55(16):1668–70. Ansel GM, Hopkins LN, Jaff MR, Rubino P, Bacharach JM, Scheinert D, et al.; Investigators for the ARMOUR Pivotal Trial. Safety and effectiveness of the INVATEC MO.MA proximal cerebral protection device during carotid artery stenting: results from the ARMOUR pivotal trial. Catheter Cardiovasc Interv. 2010 Jul;76(1):1–8. Bonati LH, Dobson J, Featherstone RL, Ederle J, van der Worp HB, de Borst GJ, et al.; International Carotid Stenting Study investigators. Long-term outcomes after stenting versus endarterectomy for treatment of symptomatic carotid stenosis: the International Carotid Stenting Study (ICSS) randomised trial. Lancet. 2015 Feb;385(9967):529–38. Brott TG, Hobson RW 2nd, Howard G, Roubin GS, Clark WM, Brooks W, et al.; CREST Investigators. Stenting versus endarterectomy for treatment of carotid-artery stenosis. N Engl J Med. 2010 Jul;363(1):11–23. Eckstein HH, Ringleb P, Allenberg JR, Berger J, Fraedrich G, Hacke W, et al. Results of the Stent-Protected Angioplasty versus Carotid Endarterectomy (SPACE) study to treat symptomatic stenoses at 2 years: a multinational, prospective, randomised trial. Lancet Neurol. 2008 Oct;7(10):893–902. Ederle J, Bonati LH, Dobson J, Featherstone RL, Gaines PA, Beard JD, et al.; CAVATAS Investigators. Endovascular treatment with angioplasty or stenting versus endarterectomy in patients with carotid artery stenosis in the Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS): long-term follow-up of a randomised trial. Lancet Neurol. 2009 Oct;8(10):898–907. Gurm HS, Yadav JS, Fayad P, Katzen BT, Mishkel GJ, Bajwa TK, et al.; SAPPHIRE Investigators. Long-term results of carotid stenting versus endarterectomy in high-risk patients. N Engl J Med. 2008 Apr;358(15):1572–9. Yadav JS, Wholey MH, Kuntz RE, Fayad P, Katzen BT, Mishkel GJ, et al.; Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy Investigators. Protected carotid-artery stenting versus endarterectomy in high-risk patients. N Engl J Med. 2004 Oct;351(15):1493–501. Zahn R, Mark B, Niedermaier N, Zeymer U, Limbourg P, Ischinger T, et al.; Arbeitsgemeinschaft Leitende Kardiologische Krankenhausärzte (ALKK). Embolic protection devices for carotid artery stenting: better results than stenting without protection? Eur Heart J. 2004 Sep;25(17):1550–8. Massop D, Dave R, Metzger C, Bachinsky W, Solis M, Shah R, et al.; SAPPHIRE Worldwide Investigators. Stenting and angioplasty with protection in patients at high-risk for endarterectomy: SAPPHIRE Worldwide Registry first 2,001 patients. Catheter Cardiovasc Interv. 2009 Feb;73(2):129–36. Bijuklic K, Wandler A, Hazizi F, Schofer J. The PROFI study (Prevention of Cerebral Embolization by Proximal Balloon Occlusion Compared to Filter Protection During Carotid Artery Stenting): a prospective randomized trial. J Am Coll Cardiol. 2012 Apr;59(15):1383–9. Cano MN, Kambara AM, de Cano SJ, Pezzi Portela LA, Paes ÂT, Costa JR Jr, et al. Randomized comparison of distal and proximal cerebral protection during carotid artery stenting. JACC Cardiovasc Interv. 2013 Nov;6(11):1203–9. Coppi G, Moratto R, Silingardi R, Rubino P, Sarropago G, Salemme L, et al. PRIAMUS—proximal flow blockage cerebral protectIon during carotid stenting: results from a multicenter Italian registry. J Cardiovasc Surg (Torino). 2005 Jun;46(3):219–27. Reimers B, Sievert H, Schuler GC, Tübler T, Diederich K, Schmidt A, et al. Proximal endovascular flow blockage for cerebral protection during carotid artery stenting: results from a prospective multicenter registry. J Endovasc Ther. 2005 Apr;12(2):156–65. Ferguson GG, Eliasziw M, Barr HW, Clagett GP, Barnes RW, Wallace MC, et al. The North American Symptomatic Carotid Endarterectomy Trial : surgical results in 1415 patients. Stroke. 1999 Sep;30(9):1751–8. Author Contacts

Ambooj Tiwari, MD, MPH

Pacific Neuroscience Institute

Department of Vascular and Interventional Neurology, Providence St. Joseph Health

2125 Arizona Ave, Santa Monica, CA 90404 (USA)

E-Mail amboojtiwari@gmail.com

Article / Publication Details

First-Page Preview

Received: April 11, 2018
Accepted: February 20, 2019
Published online: August 05, 2019
Issue release date: January 2020

Number of Print Pages: 10
Number of Figures: 1
Number of Tables: 3

ISSN: 1664-9737 (Print)
eISSN: 1664-5545 (Online)

For additional information: https://www.karger.com/INE

Copyright / Drug Dosage / Disclaimer

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.