Peer-Review ReportProximal versus Distal Protection During Carotid Artery Stenting: Analysis of the Two Treatment Approaches and Associated Clinical Outcomes
Introduction
Carotid artery stenting (CAS) has become established as a less invasive alternative procedure to carotid endarterectomy for patients with carotid artery stenosis. Systematic reviews of previously published studies on protected and unprotected CAS indicate that the use of cerebral protection devices decrease the risk of perioperative stroke 4, 7. Distal filters (e.g., Filter Wire EZ; Boston Scientific, Natick, Masssachusetts, USA) and Emboshield NAV6 (Abbott Vascular, Abbott Park, Illinois, USA) are the most commonly used type of protection devices and have been incorporated into major recent trials. An alternative approach is to use proximal protection with the MO.MA device (Invatec, Roncadelle, Italy) or the GORE Flow Reversal System (WL Gore and Associates, Flagstaff, Arizona, USA) that create blood flow cessation or flow reversal during the stenting procedure by simultaneous balloon occlusion of the external and common carotid artery. Recent studies showed a reduction in the number of ischemic lesions documented by diffusion-weighted magnetic resonance imaging (DWI-MRI) with the proximal protection approach in comparison to the distal protection approach, although that did not translate into a reduction in adverse clinical outcomes 2, 8.
The choice of a particular protection approach depends on several factors, including anatomic features of the carotid vessel (e.g., tortuous or diseased internal carotid artery distal to the lesion), stenotic lesion characteristics (e.g., hemorrhagic plaque or intraluminal thrombus), and operator experience. The goal of this study was to examine anatomic and morphologic characteristics of the stenotic lesions and compare clinical 30-day adverse event rates between the two cerebral protection groups.
Section snippets
Study Design, Setting, and Population
We conducted a single-center, retrospective review of consecutive cases of CAS in which proximal protection devices were used between January 2006 and March 2012. All procedures were done by endovascular neurosurgeons proficient in performing the stenting procedure using both proximal and distal protection devices. Patients with symptomatic and asymptomatic carotid artery stenosis were included. Patients were considered symptomatic if they had an ischemic event corresponding to the affected
Descriptive Data
We identified a total of 70 patients treated with proximal protection devices during the CAS procedure. Of those, 49 patients were treated using the MO.MA proximal protection device (Invatec) and 21 patients were treated using the GORE Flow Reversal System (WL Gore and Associates). These patients were matched (based on stenosis symptomatology, age, and gender) with 70 patients treated for CAS using distal filter protection devices (Filter Wire EZ [Boston Scientific] or Emboshield NAV6 [Abbott
Discussion
In the present study, we reviewed anatomic and morphologic characteristics of the stenotic lesions and the decision-making process when choosing proximal versus distal protection devices in patients undergoing CAS procedures performed by endovascular-trained neurosurgeons proficient in using both types of protection devices. We found that in 56 of 140 patients both types of devices could be used. Interestingly, distal filters were used in most of those patients (84%).
Other investigators have
Conclusion
Our study is the first attempt (to our knowledge) to review and compare anatomic and morphologic characteristics of stented lesions in cases of proximal versus distal protection for CAS. Our data indicate that in properly selected patients both approaches could be equally safe and effective. Further prospective studies focusing on clinical outcomes and not only imaging surrogates for cerebral embolization (such as DWI-MRI or transcranial Doppler imaging) are needed.
Acknowledgment
We thank Debra J. Zimmer for editorial assistance.
References (19)
- et al.
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) - et al.
Influence of sex on outcomes of stenting versus endarterectomy: a subgroup analysis of the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST)
Lancet Neurol
(2011) - et al.
A diffusion-weighted magnetic resonance imaging-based study of transcervical carotid stenting with flow reversal vs transfemoral filter protection
J Vasc Surg
(2012) Embolic protection in carotid artery stenting: new options
Tech Vasc Interv Radiol
(2011)- et al.
Microembolization during carotid artery stenting in patients with high-risk, lipid-rich plaque. A randomized trial of proximal versus distal cerebral protection
J Am Coll Cardiol
(2011) - et al.
Utility of high resolution MR imaging to assess carotid plaque morphology: a comparison of acute symptomatic, recently symptomatic and asymptomatic patients with carotid artery disease
Atherosclerosis
(2009) - et al.
Major carotid plaque surface irregularities correlate with neurologic symptoms
J Vasc Surg
(2002) - et al.
Carotid plaque echolucency increases the risk of stroke in carotid stenting: the Imaging in Carotid Angioplasty and Risk of Stroke (ICAROS) study
Circulation
(2004) - et al.
Significance of plaque ulceration in symptomatic patients with high-grade carotid stenosis. North American Symptomatic Carotid Endarterectomy Trial
Stroke
(1994)
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Conflict of interest statement: Dr. Hopkins receives grant/research support from Toshiba; serves as a consultant to Abbott, Boston Scientific, Cordis, Micrus, and Silk Road; holds financial interests in AccessClosure, Augmenix, Boston Scientific, Claret Medical, Endomation, Micrus, and Valor Medical; holds a board/trustee/officer position with Access Closure and Claret Medical; serves on Abbott Vascular's speakers' bureau; and has received honoraria from Bard, Boston Scientific, Cleveland Clinic, Complete Conference Management, Cordis, Memorial Health Care System, and the Society for Cardiovascular Angiography and Interventions (SCAI). Dr. Kass-Hout received research funding from Genentech Medical Educational and Research Department. Dr. Levy receives research grant support, other research support (devices), and honoraria from Boston Scientific* and research support from Codman & Shurtleff, Inc. and ev3/Covidien Vascular Therapies; has ownership interests in Intratech Medical Ltd. and Mynx/Access Closure; serves as a consultant on the board of Scientific Advisors to Codman & Shurtleff, Inc.; serves as a consultant per project and/or per hour for Codman & Shurtleff, Inc., ev3/Covidien Vascular Therapies, and TheraSyn Sensors, Inc.; and receives fees for carotid stent training from Abbott Vascular and ev3/Covidien Vascular Therapies. Dr. Levy receives no consulting salary arrangements. All consulting is per project and/or per hour. (*Boston Scientific's neurovascular business has been acquired by Stryker.) Dr. Mokin received an educational grant from Toshiba Medical Systems. Dr. Siddiqui received research grants from the National Institutes of Health (co-investigator: NINDS 1R01NS064592-01A1—not related to the present work) and the University at Buffalo (Research Development Award); holds financial interests in Hotspur, Intratech Medical, StimSox, and Valor Medical; serves as a consultant to Codman & Shurtleff, Inc., Concentric Medical, ev3/Covidien Vascular Therapies, GuidePoint Global Consulting, and Penumbra; belongs to the speakers' bureaus of Codman & Shurtleff, Inc. and Genentech; serves on an advisory board for Codman & Shurtleff; and has received honoraria from Peripheral Angioplasty and All That Jazz and American Association of Neurological Surgeons' courses, an Emergency Medicine Conference, Genentech, Neocure Group LLC, and from Abbott Vascular and Codman & Shurtleff, Inc. for training other neurointerventionists in carotid stenting and for training physicians in endovascular stenting for aneurysms. Dr. Siddiqui receives no consulting salary arrangements. All consulting is per project and/or per hour. Dr. Snyder serves as a consultant to, a member of the speakers' bureau, and has received honoraria from Toshiba. He serves as a member of the speakers' bureau for and has received honoraria from ev3 and The Stroke Group. Dr. Dumont, Ms. Chi, Mr. Mangan, and Dr Sorkin report no financial relationships.