Carotid Artery Stenting With Proximal Embolic Protection Utilizing Flow Reversal System

ABSTRACT: Carotid artery stenting is a complex endovascular intervention with an expected steep learning curve that warrants protection against microembolization and potentially disastrous adverse events. We present herein a case with the potential for microembolization mitigated by the use of proximal embolic protection utilizing a flow reversal system.

VASCULAR DISEASE MANAGEMENT 2013:10(11):E231-E233

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Case Report

A 67-year-old male was referred for carotid angiography after a recent ophthalmologic exam demonstrated left retinal artery occlusion with a history of two prior episodes of transient blurred vision consistent with transient ischemic attacks. Physical examination revealed a left carotid bruit on auscultation. Carotid duplex ultrasound confirmed high-grade left internal carotid artery (ICA) stenosis with peak systolic velocity of 518 cm/sec and antegrade vertebral artery flow with no significant obstruction of flow in the right ICA and antegrade right vertebral artery flow. 

The patient was brought to the angiography suite for elective carotid artery stenting in the setting of recurrent embolic events. Vascular access was obtained in the right common femoral artery with a 10 Fr sheath and the right femoral vein with a 6 Fr sheath. A 6 Fr internal mammary diagnostic catheter was used to selectively engage the left common carotid artery (CCA) and diagnostic angiogram revealed a 90% ulcerated stenosis in the proximal left ICA (Figure 1) with preserved intracerebral flow. A stiff angled glidewire (Terumo) was advanced into the left external carotid artery (ECA) to allow exchange for the 9.5 Fr CCA balloon sheath (Gore) into the left CCA through the 10 Fr arterial sheath. An ECA balloon wire (Gore) was then positioned at the ostium of the left ECA. Carotid flow reversal was initiated after inflation of the CCA and ECA balloons (Figure 2) with retrograde flow through the left ICA and CCA and continuous flow through the external filter into the venous system via the 6 Fr venous sheath.  A Prowater guidewire (Abbott Vascular) was advanced through the left ICA lesion into the distal segment of the artery.  A Viatrac 4 mm x 30 mm balloon (Abbott Vascular) was used to predilate the lesion with good expansion (Figure 3). An Xact 7-9 mm x 40 mm self-expanding stent (Abbott Vascular) was deployed in the left ICA extending into the CCA (Figure 4), and postdilated using a Viatrac 5 mm x 30 mm balloon (Abbott Vascular) with good expansion (Figure 5). Aspiration of debris was performed prior to deflating both the left ECA and CCA balloons. The ECA balloon wire and Prowater guidewires were withdrawn, and final angiograms confirmed excellent angiographic results with brisk flow through the left ICA (Figure 6) and preserved intracerebral flow. The patient was transferred to the intensive care unit for observation overnight and discharged home the following day on dual-antiplatelet therapy without any complications.

Discussion

Carotid artery stenting (CAS), when compared to carotid endarterectomy (CEA), has demonstrated excess microembolic burden,¹ varying with experience of operators and technical approaches while performing the procedure.² Embolic protection devices (EPDs) were designed in an effort to improve the safety profile of CAS and have significantly decreased the associated risk of microembolization.³ However, avoiding the aortic arch during CAS by inserting destination systems that directly cannulate the CCA⁴ and utilizing proximal EPDs and flow reversal systems⁵ has provided newer means of neuroprotection. Fewer embolic signals have been seen with a proximal occlusion EPD compared with a distal filter-based EPD.⁶ These developments have greatly reduced the procedural embolic risk associated with CAS and approximated the risk associated with CEA.  

Proximal EPDs such as the Mo.Ma system (Medtronic, Inc) and the Gore Flow Reversal system have demonstrated excellent clinical utility and outcomes in CAS. A systematic review of more than 2,000 CAS cases using proximal embolic protection highlighted a clinical event rate of stroke, death, and myocardial infarction of 2.25%.⁷ The ARMOUR Pivotal US IDE trial evaluating the Mo.Ma flow-arrest device enrolled 257 patients with an all-stroke and death rate of 2.7% and no strokes in the symptomatic population.⁸ The EMPIRE US IDE trial evaluating the Gore Flow Reversal system recruited 245 patients with all-stroke and death rate of 2.9% and 3.8% in the 78 symptomatic patients treated.⁹

Both CAS and CEA in qualified hands have comparable outcomes. Beyond the importance of operator experience and training for CAS, the use of proximal EPDs has significantly altered the embolization risk with CAS.¹⁰

Conclusion

Herein, we illustrate a case of ulcerated ICA stenosis that was treated successfully with CAS using proximal EPD and a flow reversal system.

Editor’s Note: Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no disclosures related to the content of this manuscript. 

Manuscript received September 9, 2013;  provisional acceptance given September 30, 2013; final version accepted October 3, 2013.

Address for correspondence: Jon C. George, MD, Director of Clinical Research, Division of Cardiovascular Medicine, Deborah Heart and Lung Center, 200 Trenton Road, Browns Mills, NJ 08015, USA. Email:   jcgeorgemd@gmail.com

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