DEFINITION OF THE PROBLEM Purpose of these guidelinesThe Clinical Practice Council of the Society for Vascular Surgery charged a writing committee with the task of updating practice guidelines, initally published in 2003, for surgeons and physicians who are involved in the preoperative, operative, and postoperative care of patients with abdominal aortic aneurysms (AAA). 1 This document provides recommendations for evaluating the patient, including risk of aneurysm rupture and associated medical co-morbidities, guidelines for selecting surgical or endovascular intervention, intraoperative strategies, perioperative care, long-term follow-up, and treatment of late complications.Decision making related to the care of patients with AAA is complex. Aneurysms present with varying risks of rupture and patient specific factors influence anticipated life expectancy, operative risk, and the need to intervene. Careful attention to the choice of operative strategy, as influenced by anatomic features of the AAA, along with optimal treatment of medical co-morbidities is critical to achieving excellent outcomes. Moreover, appropriate postoperative patient surveillance and timely intervention in the case of a late complication is necessary to minimize subsequent aneurysm-related death or morbidity. All of these clinical decisions are determined in an environment where cost-effectiveness will ultimately dictate the ability to provide optimal care to the largest possible segment of the population. Currently available clinical data sets have been reviewed in formulating these recommendations. However, an important goal of this document is to clearly identify those areas where further clinical research is necessary. Methodology and evidenceA comprehensive review of the available clinical evidence in the literature was conducted in order to generate a concise set of recommendations. The strength of any given recommendation and the quality of evidence was scored based on the GRADE system (Table I). 2 When the benefits of an intervention outweighed its risks, or, alternatively, risks outweighed benefits, a strong recommendation was noted. However, if benefits and risks were less certain, either because of low quality evidence or because high quality evidence suggests benefits and risks are closely balanced, a weak recommendation was recorded. The quality of evidence that formed the basis of these recommendations was scored as high, moderate, or low. Not all randomized controlled trials are alike and limitations may compromise the quality of their evidence. In addition, if there is a large magnitude of effect, the quality of evidence derived from observational studies may be high. Thus, quality of evidence was scored as high when additional research is considered very unlikely to change confidence in the estimate of effect; moderate when further research is likely to have an important impact in the estimate of effect; or low when further research is very likely to change the estimate of the effect.

BACKGROUND In the Carotid Revascularization Endarterectomy versus Stenting Trial, we found no significant difference between the stenting group and the endarterectomy group with respect to the primary composite end point of stroke, myocardial infarction, or death during the periprocedural period or any subsequent ipsilateral stroke during 4 years of follow-up. We now extend the results to 10 years. METHODS Among patients with carotid-artery stenosis who had been randomly assigned to stenting or endarterectomy, we evaluated outcomes every 6 months for up to 10 years at 117 centers. In addition to assessing the primary composite end point, we assessed the primary end point for the long-term extension study, which was ipsilateral stroke after the periprocedural period. RESULTS Among 2502 patients, there was no significant difference in the rate of the primary composite end point between the stenting group (11.8%; 95% confidence interval [CI], 9.1 to 14.8) and the endarterectomy group (9.9%; 95% CI, 7.9 to 12.2) over 10 years of follow-up (hazard ratio, 1.10; 95% CI, 0.83 to 1.44). With respect to the primary long-term end point, postprocedural ipsilateral stroke over the 10-year follow-up occurred in 6.9% (95% CI, 4.4 to 9.7) of the patients in the stenting group and in 5.6% (95% CI, 3.7 to 7.6) of those in the endarterectomy group; the rates did not differ significantly between the groups (hazard ratio, 0.99; 95% CI, 0.64 to 1.52). No significant between-group differences with respect to either end point were detected when symptomatic patients and asymptomatic patients were analyzed separately. CONCLUSIONS Over 10 years of follow-up, we did not find a significant difference between patients who underwent stenting and those who underwent endarterectomy with respect to the risk of periprocedural stroke, myocardial infarction, or death and subsequent ipsilateral stroke. The rate of postprocedural ipsilateral stroke also did not differ between groups. (Funded by the National Institutes of Health and Abbott Vascular Solutions; CREST ClinicalTrials.gov number, NCT00004732.)

DEFINITION OF THE PROBLEM Purpose of these guidelinesThe Clinical Practice Council of the Society for Vascular Surgery charged a writing committee with the task of updating practice guidelines, initally published in 2003, for surgeons and physicians who are involved in the preoperative, operative, and postoperative care of patients with abdominal aortic aneurysms (AAA). 1 This article is an executive summary of the main practice guidelines document and provides recommendations for evaluating the patient, including risk of aneurysm rupture and associated medical co-morbidities, guidelines for selecting surgical or endovascular intervention, intraoperative strategies, perioperative care, longterm follow-up, and treatment of late complications. 2 Decision making related to the care of patients with AAA is complex. Aneurysms present with varying risks of rupture, and patient-specific factors influence anticipated life expectancy, operative risk, and the need to intervene. Careful attention to the choice of operative strategy, as influenced by anatomic features of the AAA, along with optimal treatment of medical co-morbidities is critical to achieving excellent outcomes. Moreover, appropriate postoperative patient surveillance and timely intervention in the case of a late complication is necessary to minimize subsequent aneurysm-related death or morbidity. All of these clinical decisions are determined in an environment where cost-effectiveness will ultimately dictate the ability to provide optimal care to the largest possible segment of the population. Currently available clinical data sets have been reviewed in formulating these recommendations. However, an important goal of this document is to clearly identify those areas where further clinical research is necessary. Methodology and evidenceA comprehensive review of the available clinical evidence in the literature was conducted in order to generate a concise set of recommendations. The strength of any given recommendation and the quality of evidence was scored based on the GRADE system (Table). 3 When the benefits of an intervention outweighed its risks, or, alternatively, risks outweighed benefits, a strong recommendation was noted. However, if benefits and risks were less certain, either because of low quality evidence or because high quality evidence suggests benefits and risks are closely balanced, a weak recommendation was recorded. The quality of evidence that formed the basis of these recommendations was scored as high, moderate, or low. Not all randomized controlled trials are alike and limitations may compromise the quality of their evidence. In addition, if there is a large magnitude of effect, the quality of evidence derived from observational studies may be high. Thus, quality of evidence was scored as high when additional research is considered very unlikely to change confidence in the estimate of effect; moderate when further research is likely to have an important impact on in the

Background and Purpose-Carotid artery stenosis causes up to 10% of all ischemic strokes. Carotid endarterectomy (CEA) was introduced as a treatment to prevent stroke in the early 1950s. Carotid stenting (CAS) was introduced as a treatment to prevent stroke in 1994. Methods-The Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) is a randomized trial with blinded end point adjudication. Symptomatic and asymptomatic patients were randomized to CAS or CEA. The primary end point was the composite of any stroke, myocardial infarction, or death during the periprocedural period and ipsilateral stroke thereafter, up to 4 years. Results-There was no significant difference in the rates of the primary end point between CAS and CEA (7.2% versus 6.8%; hazard ratio, 1.11; 95% CI, 0.81 to 1.51; Pϭ0.51). Symptomatic status and sex did not modify the treatment effect, but an interaction with age and treatment was detected (Pϭ0.02). Outcomes were slightly better after CAS for patients aged Ͻ70 years and better after CEA for patients aged Ͼ70 years. The periprocedural end point did not differ for CAS and CEA, but there were differences in the components, CAS versus CEA (stroke 4.1% versus 2.3%, Pϭ0.012; and myocardial infarction 1.1% versus 2.3%, Pϭ0.032). Conclusions-In