Carotid Technologies and Protection Issam D. Moussa, MD Professor of Medicine Mayo Clinic College of Medicine Chair, Division of Cardiovascular Diseases Mayo Clinic Jacksonville, FL
Disclosure Statement of Financial Interest Grant/Research Support Consulting Fees/Honoraria Major Stock Shareholder/Equity Royalty Income Ownership/Founder Intellectual Property Rights Other Financial Benefit Medtronic, Baxter, Gilead
Cerebral Protection Strategies Distal 1 Choice ICA Device in simple Filtering lesions Stable plaque Filters, Antegrade Flow Distal Flow Blockage by ICA Occlusion Easy to access ICA Distal Flow Blockage Need to maintain distal perfusion Presence of a suitable distal landing zone in the ICA 1 st Choice Device in High Risk Lesions Flow Reversal by CCA and ECA Occlusion Thrombic lesions Ulcerated plaque Flow Reversal Proximal Flow Blockage by CCA and ECA Occlusion Long, sub-occlusive lesions Difficult to access ICA Tortuous ICA Very angulated ICA- CCA take-off Lack of a suitable ICA A-V landing Shunt zone Prox Flow Blockage
Distal Filter Protection 3.2F GORE Embolic Filter 3.5F 3.1F RX ACCUNET TM Embo shield PRO 3.6F ANGIOGUARD TM RX 3.1F 3.2F SpideRX TM FilterWire EZ TM
EPDs: Filter wires Filter-wire performances Flexibility Trackability Crossing profile Conformability Capturing capabilities Pore size and distribution Capturing volume Vessel lumen form fitting (diameter, contour, asymmetry, bends, tortuousity, etc.)
Filter conformability & capturing performances Filter fitness to the distal ICA landing zone is determined by filter frame: Concentric filter Nitinol cage Self centering is determined by the relationship between the filter cage, the polyurethane umbrella, and the landing zone Eccentric filter Nitinol loop Self centering is determined by the relationship between the nitinol loop and the landing zone Landing zone
Concentric Filter-Wire Circular surface Wall apposition Larger area of filter wall apposition at the landing zone: Better performances in regular anatomy Worse performances in complex anatomy
Eccentric Filter-Wire Circular line wall apposition Linear wall apposition of filter at the landing zone: Good performances in regular anatomy Better performances in complex anatomy
Case 1: Angled soft ulcerated plaque - Anatomical complexity distal to the lesion - Strategy 1. Prevention of distal embolization 2. Preserving original anatomy 3. Prevention of plaque prolapse (late events) Type of EPD Type of carotid stent Proximal occlusion Carotid WallStent 30 mm
Case 1: Angled soft ulcerated plaque - Anatomical complexity distal to the lesion - MO.MA: stop flow blocckage 0.014 Choice PT wire across the lesion MO.MA: distal balloon inflated in external carotid artery
Case 1: Angled soft ulcerated plaque - Anatomical complexity distal to the lesion - Carotid Wallstent 9/30 mm post-dilated by 5.5/ 20 mm balloon Final result and plaque debris collected by aspiration of 60 cc of blood
Case 2: High grade soft lesion - CCA proximal bend - Endovascular strategy 1. Secure engagement of guiding catheter in right CCA (buddy wire technique) 2. Prevention of distal embolization 3. Prevention of plaque prolapse (late events) Type of EPD Type of stent Distal filter with high capturing capabilities Nitinol, 20 mm, cylindrical, closed cell geometry
Case 2: High grade soft lesion - CCA proximal bend - Gentle straightening of prox CCA 1. Choice PT es 0.014 2. Emboschield 6 mm Guiding catheter 8f soft tip (Multipurpose 40 )
Case 2: High grade soft lesion - CCA proximal bend - Stent delivery and post-dilatation Stent: XAct 8/20 mm Balloon 5.0/20 mm
Case 2: High grade soft lesion - CCA proximal bend - Final result
Case 3: High grade soft ulcerated lesion - Type I/II aortic arch, RCCA occluded - Strategy endpoints 1. Prevention of massive distal embolization 2. Prevention of plaque prolapse (late events) Type of EPD Type of carotid stent Filter wire + proximal occlusion Carotid WallStent 40 mm
Case 3: High grade soft ulcerated lesion - Type I/II aortic arch, RCCA occluded -
Case 3: High grade soft ulcerated lesion - Type I/II aortic arch, RCCA occluded - MO.MA: ECA stop flow blockage ECA stop flow blockage EPI EZ filter-wire in ICA CCA+ECA stop flow blockage EPI EZ filter-wire in ICA Carotid Wallstent 9/30 mm
Case 3: High grade soft ulcerated lesion - Type I/II aortic arch, RCCA occluded - Total occlusion time 72 seconds
Carotid Stent Selection Self-expanding Braided mesh wire (Super Alloy) Nitinol (Nickel-Titanium) Closed-cell design Open-cell design Closed-cell design
Stent design Courtesy of Houdart, CIRSE 2005
Is there evidence that carotid stent design impact the 30 day stroke/death rate?
No!
Post CAS Events by Stent types - 3179 Pts - Post-procedural events % 4 3.5 3 2.5 2 1.5 1 0.5 P<.001 1.3 3.4 M. Bosiers, et al EJVES 2006 Closed cell Open cell 0 All Pts Courtesy: A. Cremonesi
Post CAS Events by Stent Types 3179 Patients 7 P<.001 6.3 6 M. Bosiers, et al EJVES 2006 Post-procedural events % 5 4 3 2 1 P<.001 3.4 P = ns 1.3 1.3 1.3 1.4 Closed cell Open cell 0 All Pts Sympt Pts Asympt Pts
Stent design Italian German Registry n=815 Stoke/Death event N (%) No event N (%) Total N CC stent P=0.788 26 (3.8) 663 (96.3) 689 Total 19 (3.6) 504 (96.4) 523 Asymptomatic P=0.775 P=0.765 14 (3.7) 364 (96.3) 378 Symptomatic 5 (3.4) 140 (96.6) 145 OC stent Total 7 (4.2) 159 (95.8) 166 Asymptomatic 5 (4.2)* 115 (95.8) 120 Symptomatic 2 (4.3) 44 (95.7) 46 Reimers et al, ICCA 2006
Ischemic Events @ 30 Day Follow- up Frankfurt Registry n = 627 (%) 20 15 NS NS NS NS NS 10 5 6.7% 4.3% 1% 1.4% 3.6% 1.6% 2% 1.4% 0.5%0% 0 any ischemic event TIA minor ischemic stroke major ischemic stroke/ cerebral death restenosis closed cell design open cell design Sievert et al, ICCA 2006
Does this mean that patient-specific factors should not be considered when choosing a stent? - symptom status - carotid anatomy - plaque type?
Stent design Vessel Conformability NITINOL stent Precise, Cordis Mesh-wire stent WALLSTENT, BSC
Morphologic features
Vessel tortuosity.018 Smart 7.0 x 30 mm Better conformability of Nitinol stents
Stent design Vessel wall apposition 1 2 3 Carotid Wallstent 9.0 x 30 mm
Conformability to different vessel diameters 4.1 mm 7.5 mm Baseline After 7.0x30mm Precise Safe up to 50% difference in diameter
Optical coherence tomography OCT First impressions Open cell struts Closed cell struts Reimers et al., Mirano Courtesy, Bernard Reimers
OCT: First impressions Plaque prolapse: Possible determinant of complications Not same patient! Reimers et al., Mirano
Selection of Revascularization Technique for Carotid Artery Stenosis 2011 Clinical Practice Guidelines Brott TG et al, ACC/AHA guidelines. JACC. 2011;Vol. 57, No. 8.
Summary CAS, by experience operators, is an alternative to CEA in selected symptomatic and asymptomatic patients who require carotid revascularization Risk stratification is a valuable concept to select asymptomatic patients who derive the most benefit from carotid revascularization The benefit to risk ration of CAS can be optimized by: Adhering to compelling indications to perform the procedure Pre-procedure imaging (CTA MRA) to optimize patient selection Thoughtful procedural planning and execution