Asymptomatic Carotid Stenosis: What should we do? Paul TL Chiam MBBS (S’pore), MMed, MRCP (UK), FAMS FRCP (Edin), FESC (EU), FACC (USA), FSCAI (USA) Mount Elizabeth Hospital Singapore What is the natural history?  Follow up of 640 neurologically asymptomatic patients  292 had pressure-significant internal carotid artery stenosis  348 had a carotid bruit only without a pressuresignificant lesion  Patients with asymptomatic pressure-significant carotid stenosis are at:  greater risk for stroke than a non significant occlusion (twofold) and a general population (sevenfold) JAMA 1987; 258 (19):2704-7 Which asymptomatic stenosis is at higher risk of stroke? • Risk of stroke at five years after study entry in a total of 1820 patients increased with the severity of stenosis NEJM 2000; 343: 1420-1421 • 45% of strokes in patients with asymptomatic stenosis of 60 to 99 % are attributable to lacunes or cardioembolism BEST PRACTICE FOR ASYMPTOMATIC CAROTID STENOSIS Recurrent stroke rate 1960-2010 Stroke type Ipsilateral stroke Ipsilateral stroke/TIA time Decrease 1985-2007 1985-2005 1,7% 7% 8,71% 4,04% Hong K et al Declining Stroke and Vascular Events Recurrence Rates in Secondary Prevention Trials Circulation 2011;123:2111-2119 Which asymptomatic stenosis is at higher risk of stroke? ACES (Asymptomatic Carotid Emboli Study) Prospective multicenter study Objective: to detect MES by TCD Endpoints: TIA or ipsilateral stroke Hypothesis: MES predicts ipsilateral TIA or stroke Markus HS et al Asymptomatic embolisation for prediction of stroke in the ACES: a prospective observational study Lancet Neurol 2010;9:663-671 32 primary endpoints: 26 TIA, strokes AAR ipsilateral stroke MES 3,62% No MES 0,70% HR 2,54 (95%CI 1,20-5,36) Markus HS et al Asymptomatic embolisation for prediction of stroke in the ACES: a prospective observational study Lancet Neurol 2010;9:663-671 Is there evidence for revascularization? ACAS ACST CEA BMT RRR NNT 5,1% 11,0% 54% 84 6,4% 11,8% 46% 70 13,4% 17,9% 26% 10 year risk ACST ACAS Endarterectomy for asymptomatic carotid artery stenosis JAMA 1995;273:14211428 Halliday A et al Prevention of disabling and fatal strokes by successful CEA in patients without recent neurologic symptoms: a randomised controlled trial Lancet 2004;363:1491-1502 Halliday A, et al 10-year stroke prevention after successful CEA for asymptomatic carotid stenosis (ACST-1): a multicenter randomised trial Lancet 2010;376:1074-1084 VA STUDY  Multicenter clinical trial  444 men with asymptomatic carotid stenosis shown arteriographically (50 percent or more)  Randomly assigned to optimal medical treatment including ASPIRIN plus carotid endarterectomy ( 211 patients) or optimal medical treatment alone (233 patients)  The incidence of ipsilateral neurologic events was 8.0 percent in the surgical group and 20.6 percent in the medical group (P 0.001), RR of 0.38 (95 confidence interval,( 0.22 to 0.67) N Engl J Med 1993 Jan 28;328(4):221-7 ACAS (asymptomatic carotid atherosclerosis study)  Randomized, multicenter trial  Total of 1662 patients with asymptomatic carotid artery stenosis of 60% or greater  Medical vs CEA  After a median follow-up of 2.7 years, the incidence of ipsilateral stroke and any perioperative stroke or death rate was significantly lower in the surgical group than with aspirin alone (5 versus 11 percent) for a relative risk reduction of 0.53 (95% CI 0.22-0.72)  Men had an absolute risk reduction of percent; the absolute risk reduction in women was only 1.4 percent JAMA 1995 May 10;273(18):1421-8 ACST (asymptomatic carotid surgery trial)  3120 asymptomatic patients with 60% stenosis(US)  randomized between immediate CEA and indefinite deferral of any CEA (4% per year)and were followed for up to years  The net five-year risk for all strokes or perioperative death in the CEA group was reduced by nearly half  The absolute risk reduction over five years was greater for men than for women 8.2 percent versus 4.08 Lancet 2004 May 8;363(9420):1491-502 ACST 10 year outcomes: Significant and sustained benefit from revascularization What the guidelines recommend? ESVS, SVS, AHA… • CEA is indicated in all patients with: • Asymptomatic carotid stenosis > 60% • IF periprocedural rate of death-stroke is < 3% Is there a role for carotid stenting? CREST ASYMPTOMATIC periprocedural years CEA 1,4% 2,7% CAS 2,5% 4,5% Death-stroke MI excluded SVS REGISTRY CEA CAS 2,0 % 4,6 % Combined death-stroke-MI Brott et al Stenting versus endarterectomy for treatment of carotid artery stenosis NEJM 2010;363:11-13 Giles et al Stroke and death after CEA and CAS with and without high risk criteria J Vasc Surg 2010;52:1497 In a combination of symptomatic and asymptomatic patients, there are no differences in outcome for CAS and CEA CREST Periprocedural outcomes in CREST: No difference between CAS and CEA for Asx • SAPPHIRE (n= 334) • Suitable for both treatments • Symptomatic and asymptomatic (71%); high surgical-risk • Primary end-pt (30day death/ stroke/ MI + 1-yr death / ipsilateral stroke) NEJM 2004 • 30-d death/ stroke/ MI + 3-yr death/ ipsilateral stroke 24.6% CS vs 26.9% CEA • No difference in long-term outcomes NEJM 2008 Concerns about revascularization • Marginal surgical benefit (annual ARR 1%) • Patient selection • Nature of interventions • Results “in the real world” • Reporting methods • Emerging role of CAS • Increased evidence risk of stroke is declining with the improvement of BMT Abbott AL Medical intervention alone is now best for prevention of stroke associated with asymptomatic severe carotid stenosis A systematic review Stroke 2009;573-83 What should we do? • Try to identify those at higher risk of stroke – More severe stenosis – Presence of MES etc • Life expectancy > years • Recommend revascularization for such patients (CEA vs CAS) • Low surgical risk patients  CEA • High surgical risk and suitable for stenting  CAS What should we do? • High surgical risk and unsuitable anatomy for CAS  BMT • Patients with asymptomatic carotid stenosis at LOW risk of stroke  BMT Thank you paulchiam@heartvascularcentre.com