Carotid endarterectomy at the millennium: what interventional therapy must match

Abstract

Objectives: Carotid endarterectomy (CEA) is supported by level 1 evidence as the standard treatment of severe carotid stenosis in both symptomatic and asymptomatic patients. As interventional techniques are emerging for treatment of this disease, this study was undertaken to provide a contemporary surgical standard for comparison to carotid stenting.

Patients and methods: During the interval 1989 to 1999, 2236 isolated CEAs were performed on 1897 patients (62% male, 36% symptomatic, 4.6% reoperative procedures). Study endpoints included perioperative events, patient survival, late incidence of stroke, anatomic durability of CEA, and resource utilization changes during the study. Variables associated with complications, long-term and stroke free survival, restenosis, and resource utilization were analyzed by univariate and multivariate analysis.

Results: Perioperative complications occurred in 5.5% of CEA procedures, including any stroke/death (1.4%), neck hematoma (1.7%), cardiac complications (0.5%), and cranial nerve injury (0.4%). Actuarial survival at 5 and 10 years was 72.4% (95% confidence interval [CI] 69.3-73.5) and 44.7% (95% CI 41.7-47.9) respectively, with coronary artery disease (P < 0.0018), chronic obstructive pulmonary disease (P < 0.00018) and diabetes mellitus (P < 0.0011) correlating with decreased longevity. The age- and sex-adjusted incidence of any stroke during follow-up was reduced by 22% (upper 0.35, lower 0.08) of predicted with the patient classification of hyperlipidemia (P < 0.0045) as the only protective factor. Analysis of CEA anatomic durability during a median follow-up period of 5.9 years identified a 7.7% failure rate (severe restenosis/occlusion, 4.5%; or reoperative CEA, 3.2%) with elevated serum cholesterol (P < 0.017) correlating with early restenosis. Resource utilization diminished (first versus last 2-year interval periods) for average hospital length of stay from 10.3 +/- 1.5 days to 4.3 +/- 0.7 days (P < 0.01) and preoperative contrast angiography from 87% +/- 1.4% to 10.3% +/- 4%.

Conclusions: These data delineate the safety, durability, and effectiveness in long-term stroke prevention of CEA. They provide a standard to which emerging catheter-based therapies for carotid stenosis should be compared.

FIGURE 1. Kaplan-Meyer curve depicting percent postoperative survival in months after carotid endarterectomy. Numbers at 40, 80, 120, and 160 months designate patients at risk in that time interval; (−) designates 95% confidence intervals.

FIGURE 2. Graph depicting average length of stay (-•-) and postoperative days (-o-) in days over the course of the study based on year. Bars designate standard deviation. Comparisons of first 2 and last 2 years (P < 0.01) of carotid endarterectomy procedures were significant.

FIGURE 3. Graph depicting frequency utilization of angiograms (-•-) and other axial imaging (-o-), per year in preoperative evaluation of the patients undergoing carotid endarterectomy.