Surgical endarterectomy of high-grade carotid lesions, both symptomatic and asymptomatic, has been identified as the treatment of choice for stroke prophylaxis in most patients when compared to best medical therapy (risk factor reduction and antiplatelet agents), as shown by the NASCET and ACAS studies. More careful inspection of their respective results suggests that the risk of disabling stroke or death was 1.9% in NASCET, with a 3.9% risk of minor stroke. In ACAS, the risk of major stroke or death was 0.6% when one excludes the 1.2% risk of stroke caused by diagnostic arteriography. Subsequently, carotid endarterectomy (CEA) has been performed in increasing numbers of patients, and it is now the most frequent surgical procedure performed by vascular surgeons. Despite the proven efficacy of CEA in the prevention of ischemic stroke, great interest has been generated in carotid angioplasty/ stenting (CAS) as an alternative to surgical therapy. This chapter will examine the indications, techniques, and results of this novel therapy.

While many studies, including ACAS and NASCET, have confirmed the safety and efficacy of CEA, there may in fact be categories of patients in whom CEA may not be optimal therapy. Hertzer et al. described the Cleveland Clinic experience for 2,228 consecutive CEA procedures in 2,046 patients from 1989 to 1995. The stroke and mortality rates for CEA as an isolated procedure were exemplary at 1.8% and 0.5%, respectively, for a combined rate of 2.3%. In addition, no statistical difference was found in stroke and mortality rates for asymptomatic patients, those presenting with hemispheric transient ischemic attack (TIA), or those operated for stroke with minimal residua. Those patients having combined CEA and coronary artery bypass grafting (CABG) had higher rates of peri-operative stroke (4.3%) and death (5.3%) than those patients having isolated CEA. Carotid reoperations were also associated with higher stroke (4.6%) and death rates (2%). These data lend credence to the idea that carotid endarterectomy can be performed safely in large groups of unselected patients, but they may give some insight into categories of patients who are at increased risk for operative intervention.

A follow-up study from the Cleveland Clinic by Ouriel and Hertzer et al. attempted to identify a subgroup of patients who, upon retrospective analysis, were at increased risk for CEA and therefore might be better served by CAS. From a prospective database over a 10-year period, 3,061 carotid endarterectomies were examined. A high-risk cohort (n = 594, 19.4%) was identified, based on the presence of severe (requiring angioplasty or bypass surgery within the 6 months prior to CEA) coronary artery disease (CAD), history of congestive heart failure (CHF), severe chronic obstructive pulmonary disease (COPD), or renal insufficiency (serum creatinine greater than 3 mg%). The rate of the composite endpoint of stroke/death/myocardial infarction (MI) was 3.8% for the entire group (stroke 2.1%, MI 1.2%, and death 1.1%). This composite endpoint occurred in 7.4% of those considered high risk (n = 594, 19.4%), significantly higher than in those 2,467 patients in the low-risk category (2.9%, p = 0.008). Patients in the high-risk group were further subdivided into those who had CEA alone and those in whom CEA was combined with CABG. Not surprisingly, the incidence of the composite endpoint was greater in those having combined CEA/CABG than those having CEA as an isolated procedure. In those having CEA alone, the risk of death was significantly greater in the high-risk group (p < 0.001). Importantly, however, while the risk of the combined endpoint stroke/death/MI was greater in the high-risk group, this difference did not reach statistical significance (p = 0.078). In addition, the rates of the individual endpoints of MI and stroke did not differ statistically between the high- and low-risk groups. These data from the Cleveland Clinic vascular surgery registry seem to support the notion that patients enrolled in the multicenter trials of CEA (NASCET and ACAS) were likely similar to the low-risk group, while those in the high-risk group may not in fact have had such stellar outcomes if included in multicenter trials. Other authors have called into question the very idea of “high-risk” CEA; conflicting data exist as to factors such as high lesions, reoperations, cervical radiation, and contralateral carotid occlusion. Subsequent trials have therefore focused on medically compromised, high-risk patients as those who may benefit from an alternative procedure such as CAS.