Medical (Nonsurgical) Intervention Alone Is Now Best for Prevention of Stroke Associated With Asymptomatic Severe Carotid Stenosis

Abstract

Abstract-Significant advances in vascular disease medical intervention since large randomized trials for asymptomatic severe carotid stenosis were conducted have prompted doubt over current expectations of a surgical benefit. In this systematic review and analysis of published data it was found that rates of ipsilateral and any-territory stroke (ϩ/ϪTIA), with medical intervention alone, have fallen significantly since the mid-1980s, with recent estimates overlapping those of operated patients in randomized trials. However, current medical intervention alone was estimated at least 3 to 8 times more cost-effective. In conclusion, current vascular disease medical intervention alone is now best for stroke prevention associated with asymptomatic severe carotid stenosis given this new evidence, other cardiovascular benefits, and because high-risk patients who benefit from additional carotid surgery or angioplasty/stenting cannot be identified. (Stroke. 2009;40:e573-e583.)Key Words: asymptomatic carotid stenosis Ⅲ carotid endarterectomy Ⅲ endovascular treatment Ⅲ health policy Ⅲ stroke preventionThe best intervention is prevention and the best prevention is noninvasive.A symptomatic severe carotid stenosis generally means atherosclerotic narrowing of the proximal internal carotid artery (ICA) exceeding Ϸ50% to 60% in the absence of previous referrable symptoms of stroke or transient ischemic attack (TIA). This lesion, at least in Westernized communities, becomes increasingly prevalent from the fifth decade, affecting Ϸ10% of those aged over 80 years. 1 It accounts for Ϸ12% to 21% of all anterior circulation ischemic strokes, 1 Ϸ2 to 3 times higher than the risk for less severe asymptomatic stenosis. 2,3 In many countries surgery (or carotid endarterectomy [CEA]) for asymptomatic severe carotid stenosis is supported by best practice guidelines 4 -6 and commonly recommended 7 or performed 8,9 to prevent stroke. This is largely because of the results of 3 major randomized surgical trials: the Veterans' Affairs Cooperative Study (VACS), 10 the Asymptomatic Carotid Atherosclerosis Study (ACAS), 11 and the Asymptomatic Carotid Surgery Trial (ACST) 12 conducted 1983 to 2003.Despite differing primary outcome measures, there was an overall reduction of Ϸ1% in average annual absolute stroke risk among patients who received CEA plus medical intervention. 13 However, for decades this expensive approach has been questioned because the estimated surgical benefit was marginal and highly dependent on patient selection, nature of the medical and surgical interventions used, and reporting methods. 1 Further, nonoperated patients with higher than average stroke risk who particularly benefit from CEA cannot be identified. 14 Now carotid angioplasty/stenting, with higher procedural costs 15 and similar major complication rates (at least for symptomatic patients 16 ) is being proposed as the best prophylactic intervention 17 without even randomized trial evidence of efficacy.Vascular disease medical intervention is the combination ...

Stroke Epidemiology: Advancing Our Understanding of Disease Mechanism and Therapy

“…Earlier studies found the risk of stroke with asymptomatic carotid stenosis to be approximately 1.3% per year among patients with stenosis less or equal to 75%, and approximately 3.3% annually among patients with stenosis greater than 75% [35]. The "best" medical therapy has changed because the publications of clinical trials have compared carotid endarterectomy with medical therapy for asymptomatic carotid stenosis [36]. The risk of stroke associated with asymptomatic carotid stenosis has fallen significantly during the past 20 years [36,37].…”

“…The "best" medical therapy has changed because the publications of clinical trials have compared carotid endarterectomy with medical therapy for asymptomatic carotid stenosis [36]. The risk of stroke associated with asymptomatic carotid stenosis has fallen significantly during the past 20 years [36,37]. With contemporary medical therapy, the average annual rate of ipsilateral stroke is estimated to be <1%.…”

What number of you can read but still not see? A comment on a recent survey of carotid guidelines

“…The stroke counteractive action viability of medicinal treatment alone (reassuring a sound way of life and suitable utilization of medication) has enhanced by no less than 80% since the randomized trials of CEA versus restorative treatment began [6][7][8][9]. The perception of wager ter results now in patients with ACS without procedural mediation and its suggestions for patients with SCS (counting the requirement for better patient determination and more tightly periprocedural stroke and passing rate principles) have barely affected on rule proposals.…”

“…Current rules frequently underutilize and underestimate quality, freely approved, non-randomized observational information. Such information, for instance, have demonstrated enhanced patient results with restorative treatment alone [6][7][8][9] and with CEA, [10][11][12] and a determination of significantly higher dangers from CAS [2,3].…”

Stroke Prevention-Surgical and Interventional Approaches to Carotid Stenosis

“…There is paucity of data as to the exact annual risk of stroke in patients with asymptomatic carotid stenosis on modern medical therapy. By 1 estimate, the annual risk of stroke has dropped significantlyto <1% per year with medical therapy alone, raising serious questions as to the benefit of any revascularization procedure [45]. Spence et al [46] have shown that transcranial Doppler can identify a subgroup of patients with asymptomatic stenosis who have microembolic signals that are at higher risk for stroke than those who do not have these microembolic signals.…”