Epidemiology in HK  Stroke is major cause of morbidity and mortality around the world  4th cause of mortality in HK resulting in >3000 deaths every year Department of Health 2011

Stroke  80 % of strokes : ischaemic in orgin  20 – 25 % of ischaemic stroke : carotid stenosis  Risk of stroke correlates with severity of carotid stenosis

Treatment options Medical therapy Carotid endarterectomy Carotid artery stenting

Carotid Endarterectomy (CEA)  First described in 1953  Widely used invasive treatment for significant carotid stenosis  Efficacy was established by 4 RCTs in late 1980s and early 1990s

CEA superior to medical therapy Symptomatic carotid stenosis  North American Symptomatic Carotid Endarterectomy Trial (NASCET)  Carotid stenosis 70 – 99% : 2 yrs stroke reduced from 26% to 9% (p<0.001)  Carotid stenosis 50 – 69% : 2 yrs stroke reduced from 22.2% to 15.7% (p<0.045)  Carotid stenosis <50% : no benefit  European Carotid Surgery Trial (ECST) JM Henry N Eng Jounral of Medicine 1998 PM Rothwell Lancet 1998

CEA superior to medical therapy Asymptomatic carotid stenosis  Asymptomatic Carotid Surgery Trial (ACST)  Carotid stenosis >60% : 5 yrs stroke rate reduced from 11.8% to 6.4%  10-year stroke prevention after successful carotid endarterectomy for asymptomatic stenosis (ACST-1)  10 yrs stroke rate reduced from 17.9% to 13.4%  Asmptomatic Carotid Atherosclerosis Study (ACAS) A. Halliday Lancet 2004 JAMA 1995 A. Halliday Lancet 2010

Carotid Endarterectomy (CEA)

Emerge of Carotid artery stenting (CAS) 1. Excluded elderly patients (>80 yrs) with significant comorbidites 2. Excluded high risk lesions such as restenosis after prior CEA, radiation induced stenosis CEA associated complications such as cardiovascular events, wound complications, cranial nerve injury, carotid artery dissection...

Carotid artery stenting (CAS)  First case report of carotid angioplasty appeared in early 1980 Embolic- protection device in distal artery Balloon angioplasty across stenotic area Deployment of stent Withdrawl of embolic – protection device

1st RCT (CEA Vs CAS)  Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS)  Performed only angioplasty without EPD  NO significant difference in 30-day incidence of death or disabling stroke (6.4% in CAS vs 5.9% in CEA)  8 yrs follow up : Higher restenosis and stroke rate (21.1% in CAS vs 15.4% in CEA) CAVATAS Investigators Lancet 2001 CAVATAS Investigators Lancet 2009

RCTssssssss (CEA Vs CAS) Trial No of patients FindingConclusion SPACE days stroke and death rate CAS : 6.84% CEA : 6.34% (p = 0.09) Failed to prove non- inferiorty of CAS EVA – 3S days stroke and death rate CAS : 9.6% CEA : 3.9% (p = 0.01) Terminated early due to high stroke rate in CAS group ICSS days stroke, MI and death rate CAS : 8.5% CEA : 5.2% (p = 0.006) CEA should remain the treatment of choice

RCTssssssss (CEA Vs CAS) widely criticized  SPACE, EVA-3S and ICSS were widely criticized  NO roll in phase e.g. SPACE trial : eligible operators for CAS arm do not need prior carotid stenting experience  Use of EPD was not mandatory e.g. SPACE trial : used in 27% of patients

CREST Trial  Stenting versus Endartrectomy for Treatment of Carotid – Artery Stenosis (CREST)  National Institutes of Health-sponsored study based in United States from 2000 to 2008  2522 patients including both symptomatic and asymptomatic carotid stenosis  Lead in phase   Single carotid stent with EPD systems Thomas G. Brott N Eng Journal of Med 2010

CREST – Periprocedural findingOutcome CEA % CAS % p value Periprocedural stroke+MI+death Periprocedural stroke - Major ipslateral stroke - Minor ipsilateral stroke Periprocedural MI Periprocedural death Periprocedural cranial nerve injury Thomas G. Brott N Eng Journal of Med 2010

CREST – 4 years finding Outcome CEA % CAS % p value 4 years stroke+MI+death years stroke Thomas G. Brott N Eng Journal of Med 2010

CREST Finding – Age Thomas G. Brott N Eng Journal of Med 2010  Younger patients have better outcome with CAS while older patients have better outcome with CEA  120 days stroke and death risk  Age <70 yrs : CAS – 5.8% CEA – 5.7%  Age >70 yrs : CAS – 12% CEA – 5.9%  Arterial tortuosity and calcification in elderly prones to catheter provoked cerebral emboli

CEA = CAS ??

Are these conclusion justified? 1. Primary purpose of CEA and CAS is to prevent death and stroke Outcome CEA % CAS % p value Perioperative stroke+MI+death Perioperative stroke - Major ipslateral stroke - Minor ipsilateral stroke Perioperative MI Perioperative death Perioperative cranial nerve injury

Are these conclusion justified? 2. Stroke ≠ Myocardial Infarction  Quality-of-life analyses indicates that stroke had a greater adverse effect on heath-status than MI  Even minor stroke had full motor and sensory recovery, patient often have other brain damage

Are these conclusion justified? 3. CAS operators in CREST have a high level of experience and skill, CREST results may not be representative in real world

Carotid Endarterectomy (CEA) Carotid Artery Stenting (CAS) ProsCons ProsCons  Periprocedural stroke  MI  Periprocedural MI  Periprocedural stroke  Cranial nerve injury No cranial nerve injury  Wound infection  Wound infection Required GANo GA required Longer recoveryMinimally invasive

Matching patient to intervention  Treatment decisions depends on patient- specific factors 1. Risk factors for CEA 2. Risk factors for CAS Medical Surgical / Anatomical

Risk factors for CEA Medical risk factors  CHF and left ventricular dysfunction  Unstable angina or recent MI (<30 days)  Coronary artery disease (CAD)  Open heart surgery needed within 6 weeks  Severe pulmonary dysfunction Mozes J Vasc Surg 2004   risk of worse outcome remains controversial  Similar stroke and death rate between low and high risk patient  Too high risk  Medical treatment

Risk factors for CEA Surgical / Anatomical risk factors Surgical Factors  Restenosis after prior CEA  Previous ablative neck surgery (e.g. radical neck dissection, laryngectomy)  Previous neck irradiation  Contralateral vocal cord paralysis  Tracheostomy

Risk factors for CEA S urgical / Anatomical risk factors Anatomical Factors  High carotid bifurcation (above C2)  Extension of athersclerotic lesion into intracranial ICA or proximal CCA below clavicle

Risk factors for CAS

Individualized management  Optimal treatment selection specific for each patient Lowest morbidty rate  Lowest morbidty rate  Most favorable outcomes

Management Algorithm HIGH risk for surgery Favourable anatomy for CAS CASCAS Unfavourable anatomy for CAS CEACEA Symptomatic >= 50% CS LOW risk for surgery Asymptomatic >= 70% CS BMTBMT

Conclusion  CEA continues to be the gold standard for treatment for carotid stenosis  CAS will evolve as a safe and efficacious therapy for carotid stenosis  Individualized treatment plan