Stenting for Intracranial Atherosclerosis: Who, When, and How Alex - PowerPoint PPT Presentation

Stenting for Intracranial Atherosclerosis: Who, When, and How Alex Abou-Chebl, MD, FSVIN Stroke Medical Director Baptist Health Louisville

Disclosure Statement of Financial Interest Within the past 12 months, I or my spouse/partner have had a financial interest/arrangement or affiliation with the organization(s) listed below. Affiliation/Financial Relationship Company • • Consulting Fees/Honoraria Silk Road Medical • • Consulting Fees/Honoraria Angiodynamics

Alex Abou-Chebl, MD

SAMMPRIS Criticisms • • 20 Cases Vetting Average 7days to Only 3 Wingspan, no need for  randomization atherosclerosis experience ½ patients w ICH Tx 17days •  General Anesthesia after event- Low WASID risk • Cross lesion with • No assessment of microcatheter and exchange for balloon cerebrovascular reserve • Initially no post-dilation • No angiographic collateral allowed, protocol changed criteria after • • Perforator strokes included SBP<150mmHg post-op • SBP<120 reduced risk of ICH  Stenting vessels <2.5mm with CAS • • Lesion characteristics not No assessment of ASA/Plavix response considered Mori Classification  Abou-Chebl A, Steinmetz H. Stroke 2012:43(2):616-620 Alex Abou-Chebl, MD

Pathophysiology • Thrombotic occlusion Acute plaque rupture  Thrombosis  Vessel Occlusion   Ischemia • Artery-to-artery embolism Acute plaque rupture/Turbulence/Sheer Stress  Thrombosis   Embolism  Ischemia • Hypoperfusion Flow-limiting stenosis  Autoregulation Failure   Hypoperfusion  Ischemia • Branch Origin Occlusion- Perforator Syndromes Atherosclerotic plaque buildup  Encroachment/Occlusion  ostia of perforators  Ischemia • Combination- Impaired “ Washout of Emboli ” Alex Abou-Chebl, MD

Determinants of Risk & Severity of Clinical Manifestations • Stenosis Characteristics • CRP & Fibrinogen predictors • Collateral Blood Flow of recurrent CAD and stroke Cerebrovascular Reserve  • Bang OY teal. JNNP 2005 • Freq & Size of Embolism • Arenillas JF et al. Stroke. • 2003;34:2463-2468. Severity of Hypoperfusion • Duration of Ischemia • Underlying Brain Substrate Neuronal Reserve  P< .0001 • ILOD-related events Age % Survival free of • Medical Co-morbidities Hyper/Hypoglycemia  Patients with CRP  1.41 mg/dl Patients with CRP > 1.41 mg/dl Months after inclusion

Why Differentiating Hemodynamic vs. Perforator Ischemia Matters • Volume of Territory at Risk • Eloquence of Tissue at Risk • Maximizing Benefit from Revascularization • Reducing Risk of Revascularization Alex Abou-Chebl, MD

Importance of Collaterals WASID Angiographic Dataset N=287 (of 569) • “Across all stenoses extent of collaterals was a predictor for subsequent stroke in the symptomatic arterial territory” None vs. good HR 1.14, CI 0.39-3.30  Poor vs. good HR 4.36; 95% CI, 1.46-13.07; p < 0.0001  • 70-99% stenoses, more extensive collaterals  risk of territorial stroke None vs. good HR 4.60; 95% CI, 1.03-20.56  Poor vs. good HR 5.90; 95% CI, 1.25-27.81, p = 0.0427  • 50-69%, presence of collaterals associated with  likelihood of stroke None vs. good HR 0.18; 95% CI, 0.04-0.82  Poor vs. good HR 1.78; 95% CI, 0.37-8.57; p < 0.0001  • Multivariate analyses: extent of collaterals independent predictor for subsequent stroke None vs. good HR 1.62; 95% CI, 0.52-5.11  Poor vs. good, 4.78; 95% CI, 1.55-14.7; p = 0.0019  Liebeskind D, et al. Ann Neurolo 2011;69:963-74 Alex Abou-Chebl, MD

Decreased Flow Reserve in Coronary Circulation • Stenting of non-ischemic stenoses has no benefit compared to Med Rx only • Stenting of ischemia-related stenoses improves Sx and outcome • In multivessel CAD, identifying which stenoses cause ischemia difficult:  Non-invasive tests often unreliable  Coronary angiography often results in under- or overestimation of functional stenosis severity

Assessment of Cerebrovascular Reserve • Acetazolamide SPECT  Useful in combination with an anatomical study  Measures hemodynamic significance of stenosis  Identify pts. who may benefit from revascularization  Annual Stoke Rates as high 25% • Eskey & Sanelli Neuroimag Clin N Am 2005;15 • Ozgur H, et al. AJNR 2001

Natural History of ICAD: A Dynamic Process • Wong et al. Stroke 2005;33:532-6.  Serial TCD study of 143 symptomatic MCA stenoses • At 6 month TCD – 29% Normalized 4.8% Recurrent Events – 62% Stable 12.5% Recurrent Events – 9% Progressed 38.5% Recurrent Events – Total 10.5% Recurrent Events • Arenillas et al. Stroke 2001;32:2898-2904  26.5month TCD study of 40 symptomatic MCA • 32.5% Progressed • 20% recurrent events  Predictor of Stroke • Tandem stenosis in cervical ICA • Lesion Progression Alex Abou-Chebl, MD

Mori Classification • Lesion based • Length • Eccentricity • Predicts complications and reocclusion • Type A: concentric, <5mm, smooth 8% • Type B: eccentric, 5-10mm, angulated, irregular 26% • Type C: >10mm, extreme angulation, total occl. 87% Mori T, Kazita K, Chokyu K, Mima T, Mori K. Short-term arteriographic and clinical outcome after cerebral angioplasty and stenting for intracranial vertebrobasilar and carotid atherosclerotic occlusive disease. AJNR Am J Neuroradiol 2000 Feb;21:249-254. Alex Abou-Chebl, MD

The Less Than Ideal ICAD Patient  42yo woman with coital headache and stroke Alex Abou-Chebl, MD

Technical Result Alex Abou-Chebl, MD

Indications • >70% symptomatic stenosis Focal, concentric, non-angulated, away from bifurcation  Distal territory Sx- no perforator Sx  • Failed medical Rx Antiplatelet- dual  Statin  ACE-I  • Abnormal cerebrovascular reserve Radiographic  Clinical  • Pressure dependent • Orthostatic Sx • Progressive stenosis despite medical Rx Alex Abou-Chebl, MD

Timing of Intervention • Hyperperfusion syndrome can complicate CEA and CAS ~1.1% with 0.6% risk of ICH  80% fatality rate Abou-Chebl A, et al. J Am Coll Cardiol 2004; 43(9):1596-1601 • Small (N=18) series suggested high complication rates ~50% w early intracranial intervention Gupta R, et al. Neurology 2003;61:1729 – 1735 • Significant risk with delay in Tx- 56% recurrent events in 28days Kozak O, et al. Neurosurgery 2011;69:334 – 343 • SAMMPRIS- risk of ICH independent of timing of intervention relative to index event Fiorella D, et al. Stroke 2012;43:2682-2688

Approach • Local anesthesia  Intraprocedural neurological assessments guide therapeutic approach • Primary stenting for vessels >2.5mm diameter  PTA for smaller vessels  Bailout stenting • No wire exchanges or crossing with microcatheter  Cross with wire in balloon • Slowly predilate all lesions  NTG  Size balloon 0.8:1  Never oversize or use stiff wires and balloons Alex Abou-Chebl, MD

Intra-procedural Patient Monitoring • 67% Developed Headache Balloon Inflation 79.2%  Wire Positioning 62.5%  Stent Delivery 20.9%  Stent Deployment 16.7%  • 4.8% Developed Sx of Ischemia 2/3 Brainstem Hypoperfusion during PTA  • Decrease Inflation Duration 1/3 Hemispheric after Completion of Intervention  • Repeat Angiogram  Stent Thrombosis • GPIIb/IIIa Inhibitor • Successful Recanalization  Recovery Abou-Chebl A, et al. J Neuroimaging 2006;16(3): 216-223 Alex Abou-Chebl, MD

Clopidogrel Response and Risk of Peri- procedural Thrombotic Complications with Cerebrovascular Interventions • Unpublished data  N=71 (2000-2002)  Optical Platelet Aggregometry • ADP and Arachidonic Acid Patients without Patients with Thrombotic Thrombotic Total Complication Complication 60 53 7 Endovascular ADP %- aggregation 33±16.3% 31±14.8% 54.6±16.2% p=0.008 (mean ± SD) AA %- aggregation 22.6±10.2 22.3±10.3% 26±8.7% p=0.32 ADP- adenosine diphosphate, SD- standard deviation, AA- arachidonic acid

Importance of Experience Gray et al: JACC Interv 2011 Smout J, Macdonald S, Stansby G International Journal of Stroke. Vol5, Dec 2010; 477-482 Alex Abou-Chebl, MD

U.S.-China Multicenter Balloon Expandable vs. Self-Expanding Stent Registry • 670 lesions treated in 637 patients • Mean age 57±13 years • Location of stent placement:  MCA 270 (40%)  Posterior circulation 263 (39%)  Intracranial ICA 137 (21%). • Stent type:  BMS 68%, DES 5%, SES 32%  Technical failure rate: BMS 7.1% and SES 1.4%, (p<0.001) Jiang W, Cheng-Ching E, Abou-Chebl A , et al. Neurosurgery 2011 Alex Abou-Chebl, MD

Results • 30 day peri-procedural stroke or death 6.1% • Deaths 0.94% • Independent Predictors of Stroke or Death OR 95% CI p Variable Treatment < 24 hrs 4.0 1.6 -6.7 < 0.001 0.13 – 0.72 Mori Type A 0.31 0.007 Alex Abou-Chebl, MD

Summary • Intracranial Atherosclerosis is Common • With Med Tx Recurrence Rates are ~12-22%/yr  Aspirin+clopidogrel+atorva/rosuvastatin is “Best” Medical Therapy • No role for Warfarin • PTA/Stenting safe and effective in selected symptomatic patients  Most effective in patients with decreased cerebrovascular reserve • Treatment should not be delayed in non-disabled patients • Operator experience and appropriate technique are critical for success Alex Abou-Chebl, MD