10-year stroke prevention after successful carotid endarterectomy for asymptomatic stenosis (ACST-1): a multicentre randomised trial

Abstract

SummaryBackgroundIf carotid artery narrowing remains asymptomatic (ie, has caused no recent stroke or other neurological symptoms), successful carotid endarterectomy (CEA) reduces stroke incidence for some years. We assessed the long-term effects of successful CEA.MethodsBetween 1993 and 2003, 3120 asymptomatic patients from 126 centres in 30 countries were allocated equally, by blinded minimised randomisation, to immediate CEA (median delay 1 month, IQR 0·3–2·5) or to indefinite deferral of any carotid procedure, and were followed up until death or for a median among survivors of 9 years (IQR 6–11). The primary outcomes were perioperative mortality and morbidity (death or stroke within 30 days) and non-perioperative stroke. Kaplan-Meier percentages and logrank p values are from intention-to-treat analyses. This study is registered, number ISRCTN26156392.Findings1560 patients were allocated immediate CEA versus 1560 allocated deferral of any carotid procedure. The proportions operated on while still asymptomatic were 89·7% versus 4·8% at 1 year (and 92·1% vs 16·5% at 5 years). Perioperative risk of stroke or death within 30 days was 3·0% (95% CI 2·4–3·9; 26 non-disabling strokes plus 34 disabling or fatal perioperative events in 1979 CEAs). Excluding perioperative events and non-stroke mortality, stroke risks (immediate vs deferred CEA) were 4·1% versus 10·0% at 5 years (gain 5·9%, 95% CI 4·0–7·8) and 10·8% versus 16·9% at 10 years (gain 6·1%, 2·7–9·4); ratio of stroke incidence rates 0·54, 95% CI 0·43–0·68, p<0·0001. 62 versus 104 had a disabling or fatal stroke, and 37 versus 84 others had a non-disabling stroke. Combining perioperative events and strokes, net risks were 6·9% versus 10·9% at 5 years (gain 4·1%, 2·0–6·2) and 13·4% versus 17·9% at 10 years (gain 4·6%, 1·2–7·9). Medication was similar in both groups; throughout the study, most were on antithrombotic and antihypertensive therapy. Net benefits were significant both for those on lipid-lowering therapy and for those not, and both for men and for women up to 75 years of age at entry (although not for older patients).InterpretationSuccessful CEA for asymptomatic patients younger than 75 years of age reduces 10-year stroke risks. Half this reduction is in disabling or fatal strokes. Net benefit in future patients will depend on their risks from unoperated carotid lesions (which will be reduced by medication), on future surgical risks (which might differ from those in trials), and on whether life expectancy exceeds 10 years.FundingUK Medical Research Council, BUPA Foundation, Stroke Association.

Gender differences in patients with carotid stenosis

“…According to ACST, men have a significant lower risk of stroke and perioperative death within 5 years after CEA than women (ARR: 8.2 and 4.1 %) [9,20,21]. However, after 10 years, women also benefited (perioperative stroke: 5.5 %, p < 0.02, not perioperative stroke: 6.3 %, p = 0.006 in men; 5.8 %, p = 0.05 and 8.2 %, p = 0.003 in women) [23].…”

Clinical considerations in the management of asymptomatic carotid artery stenosis

“…Moreover, surgery was shown to be safe, with a perioperative neurological complication rate of less than 3%. 12,20 In a recent 10-year update on the findings of the ACST, Halliday and colleagues 19 reported a sustained benefit with carotid endarterectomy in stroke risk reduction. Half of this reduction has been in disabling or fatal strokes.…”

“…By 10 years, the overall risk of stroke (including perioperative events) was 13.4% for those undergoing early operation compared with 17.9% with delayed or no carotid endarterectomy. 19 Currently, carotid endarterectomy remains the gold standard for asymptomatic patients with an incidental asymptomatic carotid artery stenosis of 60% or greater.…”

S3-Leitlinie Extracranielle Carotisstenose

“…Ein signifikanter Vorteil der CEA bei asymptomatischen Stenosen ergibt sich erst nach mehreren Jahren (ca. 5), für Frauen sogar erst nach noch länge-rer Zeitspanne [8]. Daher kann nicht davon ausgegangen werden, dass Patienten mit einer kürzeren Lebenserwartung von der primärpräventiven CEA profitieren.…”