GUIDELINES FOR CAROTID ENDARTERECTOMY - A MULTIDISCIPLINARY CONSENSUSSTATEMENT FROM THE AD-HOC-COMMITTEE, AMERICAN-HEART-ASSOCIATION

Background and Purpose Indications for carotid endarterectomy have eng endered considerable debate among experts and have resulted in publica tion of retrospective reviews, natural history studies, audits of comm unity practice, position papers, expert opinion statements, and finall y prospective randomized trials. The American Heart Association assemb led a group of experts in a multidisciplinary consensus conference to develop this statement. Methods A conference was held July 16-18, 1993 , in Park City, Utah, that included recognized experts in neurology, n eurosurgery, vascular surgery, and healthcare planning. A program of c ritical topics was developed, and each expert presented a talk and pro vided the chairman with a summary statement. From these summary statem ents a document was developed and edited onsite to achieve consensus b efore final revision. Results The first section of this document revie ws the natural history, methods of patient evaluation, options for med ical management, results of surgical management, data from position st atements, and results to date of prospective randomized trials for sym ptomatic and asymptomatic patients with carotid artery disease. The se cond section divides 96 potential indications for carotid endarterecto my, based on surgical risk, into four categories: (1) Proven: This is the strongest indication for carotid endarterectomy; data are supporte d by results of prospective contemporary randomized trials. (2) Accept able but not proven: a good indication for operation; supported by pro mising but not scientifically certain data. (3) Uncertain: Data are in sufficient to define the risk/benefit ratio. (4) Proven inappropriate: Current data are adequate to show that the risk of surgery outweighs any benefit. Conclusions Indications for carotid endarterectomy in sym ptomatic good-risk patients with a surgeon whose surgical morbidity an d mortality rate is less than 6% are as follows. (1) Proven: one or mo re TIAs in the past 6 months and carotid stenosis greater than or equa l to 70% or mild stroke within 6 months and a carotid stenosis greater than or equal to 70%; (2) acceptable but not proven: TIAs within the past 6 months and a stenosis 50% to 69%, progressive stroke and a sten osis greater than or equal to 70%, mild or moderate stroke in the past 6 months and a stenosis 50% to 69%, or carotid endarterectomy ipsilat eral to TIAs and a stenosis greater than or equal to 70% combined with required coronary artery bypass grafting; (3) uncertain: TIAs with a stenosis <50%, mild stroke and stenosis <50%, TIAs with a stenosis <70 % combined with coronary artery bypass grafting, or symptomatic, acute carotid thrombosis; (4) proven inappropriate: moderate stroke with st enosis <50%,, not on aspirin; single TIA, <50% stenosis, not on aspiri n; high-risk patient with multiple TIAs, not on aspirin, stenosis <50% ; high-risk patient, mild or moderate stroke, stenosis <50%, not on as pirin; global ischemic symptoms with stenosis <50%; acute dissection, asymptomatic on heparin. Indications for carotid endarterectomy in asy mptomatic good-risk patients performed by a surgeon whose surgical mor bidity and mortality rate is less than 3% are as follows. (1) Proven: none. As this statement went to press, the National Institute of Neuro logical Disorders and Stroke issued a clinical advisory stating that t he Institute has halted the Asymptomatic Carotid Atherosclerosis Study (ACAS) because of a clear benefit in favor of surgery for patients wi th carotid stenosis greater than or equal to 60% as measured by diamet er reduction. When the ACAS report is published, this indication will be recategorized as proven. (2) acceptable but not proven: stenosis >7 5% by linear diameter; (3) uncertain: stenosis >75% in a high-risk pat ient/surgeon (surgical morbidity and mortality rate >3%), combined car otid/coronary operations, or ulcerative lesions without hemodynamicall y significant stenosis; (4) proven inappropriate: operations with a co mbined stroke morbidity and mortality >5%.